gills bay 132 kv environmental statement: volume 2: main ......gills bay 132 kv lt000022 volume 2:...

August 2015

Gills Bay 132 kV Environmental Statement: Volume 2: Main Report

Scottish Hydro Electric Transmission Plc Gills Bay 132 kV

LT000022 Volume 2:

Table of Contents

VOLUME 2 MAIN REPORT - TABLE OF CONTENTS

Abbreviations

Chapter 1 Introduction 1.1 Introduction 1.2 Development Need 1.3 Environmental Impact Assessment (EIA) Screening 1.4 Contents of the Environmental Statement 1.5 Structure of the Environmental Statement 1.6 The Project Team 1.7 Notifications

Chapter 2 Description of Development 2.1 Introduction 2.2 The Proposed Development 2.3 Limits of Deviation 2.4 OHL Design 2.5 Underground Cable Installation 2.6 Construction and Phasing 2.7 Reinstatement 2.8 Construction Employment and Hours of Work 2.9 Construction Traffic 2.10 Construction Management 2.11 Operation and Management of the Transmission Connection

Chapter 3 Environmental Impact Assessment Methodology 3.1 Summary of EIA Process 3.2 Stakeholder Consultation and Scoping 3.3 Potentially Significant Issues 3.4 Non-Significant Issues 3.5 EIA Methodology 3.6 Cumulative Assessment 3.7 EIA Good Practice

Chapter 4 Route Selection and Alternatives 4.1 Introduction 4.2 Development Considerations 4.3 Do-Nothing Alternative 4.4 Alternative Corridors 4.5 Alternative Routes and Conductor Support Types within the Preferred Corridor

Chapter 5 Planning and Policy Context 5.1 Introduction 5.2 Development Considerations 5.3 National Policy 5.4 Regional Policy

Scottish Hydro Electric Transmission Plc

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Volume 2: Table of Contents LT000022

5.5 Local Policy 5.6 Other Guidance 5.7 Summary

Chapter 6 Landscape and Visual Amenity 6.1 Introduction 6.2 Legislation and Policy Context 6.3 Issues Identified During Consultation 6.4 Assessment Methodology 6.5 Baseline Conditions 6.6 Potential Effects 6.7 Mitigation 6.8 Assessment of Residual Effects 6.9 Cumulative Effects 6.10 Summary of OHL Significant Effects 6.11 Summary of Underground Cable Significant Effects

Chapter 7 Ecology 7.1 Introduction 7.2 Legislation and Policy Context 7.3 Issues Identified During Consultation 7.4 Assessment Methodology 7.5 Baseline Conditions 7.6 Potential Impacts 7.7 Mitigation 7.8 Assessment of Residual Impacts 7.9 Cumulative Effects 7.10 Summary of OHL Impacts 7.11 Summary of Underground Cable Impacts

Chapter 8 Ornithology 8.1 Introduction 8.2 Legislation and Policy Context 8.3 Issues Identified During Consultation 8.4 Assessment Methodology 8.5 Baseline Conditions 8.6 Potential Impacts 8.7 Mitigation 8.8 Assessment of Residual Impacts 8.9 Cumulative Effects 8.10 Summary

Chapter 9 Cultural Heritage and Archaeology 9.1 Introduction 9.2 Legislation and Policy Context 9.3 Issues Identified During Consultation 9.4 Assessment Methodology 9.5 Baseline Conditions 9.6 Potential Impacts


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9.7 Mitigation 9.8 Assessment of Residual Impacts 9.9 Cumulative Effects 9.10 Summary of OHL Impacts 9.11 Summary of Underground Cable Impacts

Chapter 10 Geology, Hydrogeology and Hydrology 10.1 Introduction 10.2 Issues Identified During Consultation 10.3 Assessment Methodology 10.4 Baseline Conditions 10.5 Potential Impacts 10.6 Mitigation 10.7 Assessment of Residual Impacts 10.8 Cumulative Impacts 10.9 Summary of OHL Impacts 10.10 Summary of Underground Cable Impacts

Chapter 11 Soils, Land Use and Agriculture 11.1 Introduction 11.2 Legislation and Policy Context 11.3 Issues Identified During Consultation 11.4 Assessment Methodology 11.5 Baseline Conditions 11.6 Potential Impacts 11.7 Mitigation 11.8 Assessment of Residual Impacts 11.9 Cumulative Impacts 11.10 Summary

Chapter 12 Traffic and Transport 12.1 Introduction 12.2 Legislation and Policy Context 12.3 Issues Identified During Consultation 12.4 Assessment Methodology 12.5 Baseline Conditions 12.6 Potential Impacts 12.7 Mitigation 12.8 Assessment of Residual Impact 12.9 Cumulative Impacts 12.10 Summary

Chapter 13 Noise 13.1 Introduction 13.2 Legislation and Policy Context 13.3 Issues Identified During Consultation 13.4 Assessment Methodology 13.5 Baseline Conditions 13.6 Potential Impacts


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13.7 Mitigation 13.8 Assessment of Residual Impacts 13.9 Cumulative Impacts 13.10 Summary of OHL Impacts

Chapter 14 Schedule of Mitigation 14.1 Introduction


LT000022 Volume 2:

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VOLUME 2 MAIN REPORT – LIST OF TABLES

Chapter 2 Description of Development Table 2.1: Indicative Construction Phasing Table 2.2: Schedule of Likely Access and Egress Points onto Adopted Road

Network. Table 2.3: Summary of Predicted Construction Traffic Generation Table 2.4: Predicted EMF, Typical EMF and UK Exposure Guidelines

Chapter 3 Environmental Impact Assessment Methodology Table 3.1: Consultee List Table 3.2: Non-Significant Issues

Chapter 5 Planning and Policy Context Table 5.1: Material Policies in the Highland-wide Local Development Plan Table 5.2: Statutory Supplementary Guidance adopted by Highland Council Table 5.3: Scottish Government Guidance Table 5.4: Highland Council Planning Guidance

Chapter 6 Landscape and Visual Amenity Table 6.1: Issues Identified During Consultation Table 6.2: Definitions of Landscape Sensitivity Table 6.3: Definitions of Magnitude of Landscape Change Table 6.4: Guide Criteria of Visual Sensitivity Table 6.5: Guide Criteria for Magnitude of Visual Change Table 6.6: Guide for determination of likely Landscape and Visual Effect Table 6.7: Significance of Likely Effect Table 6.8: Description of Landscape Character Types Table 6.9: Landscape Designations Table 6.10: Effects on the Landscape Resource - OHL Table 6.11: Effects on the Landscape Resource – underground cable Table 6.12: Summary of potential effects on Visual Amenity - OHL Table 6.13: Effects of the Proposed Development on Visual Amenity – underground

cable Table 6.14: Cumulative Assessment Table 6.15: Significant Operational Effects on the Landscape Resource – OHL Table 6.16: Significant Effects of the OHL on Visual Amenity

Chapter 7 Ecology Table 7.1: Issues Identified during Consultation Table 7.2: Geographic Conservation Values Table 7.3: Impact Characterisation Table 7.4: Desk Study Results within LOD of Proposed Development Table 7.5: Summary of Potential Impacts of the Proposed Development, Mitigation

and Residual Impacts of the OHL Table 7.6: Summary of Potential Impacts of the Proposed Development, Mitigation

and Residual Impacts of the Underground Cable


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Chapter 8 Ornithology Table 8.1: Issues Identified During Consultation Table 8.2: Geographic Conservation Values Table 8.3: Impact Characterisation Table 8.4: Breeding Bird Survey (Also shown on Figures 8.61a-f) Table 8.5: Breeding Wader Survey (Also shown on Figures 8.62a-f) Table 8.6: Cumulative Collision Risk Table 8.7: Summary of Potential Impacts of the Proposed Development, Mitigation



Chapter 9 Archaeology and Cultural Heritage Table 9.1: Issues Identified during Consultation Table 9.2: Cultural Heritage Viewpoints Table 9.3: Importance of Cultural Heritage Assets Table 9.4: Magnitude of Physical (Construction) Impacts Table 9.5: Significance of Impacts Table 9.6: Contribution of Setting to Understanding and Appreciation of a Cultural

Heritage Asset Table 9.7: Sensitivity of Setting of an Asset Table 9.8: Magnitude of Impacts on Setting Table 9.9: Significance of Impact on Setting Table 9.10: Significance Criteria Table 9.11: Summary of Potential Impacts of the Proposed Development, Mitigation


and Residual Impacts of the Underground Cable Elements

Chapter 10 Geology, Hydrogeology and Hydrology Table 10.1: Issues Identified During Consultation Table 10.2: Baseline Characterisation Table 10.3: Sensitivity of Environmental Resource Table 10.4: Magnitude of Impact on a Receptor Table 10.5: Significance Criteria Table 10.6: Summary of Potential Impacts of the Proposed Development, Mitigation



Chapter 11 Soils, Land Use and Agriculture Table 11.1: Issues Identified during Consultation Table 11.2: Definition of Sensitivity of Soils, Land Use and Agriculture Table 11.3: Magnitude of Effect Table 11.4: Significance Criteria Table 11.5: LCA Class & Division Details Table 11.6: Estimated Indicative Excavation Volumes Table 11.7: Summary of Potential Impacts of the Proposed Development, Mitigation

and Residual Impacts – OHL and underground cable


LT000022 Volume 2:

Table of Contents

Chapter 12 Traffic and Transport Table 12.1: Issues Identified During Consultation Table 12.2: Receptor Sensitivity Table 12.3: Impact Magnitude Table 12.4: Matrix for Determination of Significance of Effect Table 12.5: Existing Traffic Flows (Weekday Average Two Way Flows) Table 12.6: Speed Summary (Weekday Average Two Way) Table 12.7: Accident Data Summary Table 12.8: 2018 Base Traffic Flows (Weekday Average Two Way Flows) Table 12.9: Summary of Predicted Construction Traffic Generation Table 12.10: Weekday Construction Traffic (Weekday Average Two Way Flows) Table 12.11: 2018 Total Weekday Flows (Weekday Average Two Way Flows) Table 12.12: Percentage Impact Increase 2018 Base v 2018 Total (Weekday

Average Two Way Flows) Table 12.13: Summary of Potential Impacts of the Proposed Development, Mitigation

and Residual Impacts

Chapter 13 Noise Table 13.1: Issues Identified During Consultation Table 13.2: Adopted Significance Criteria for Operational Noise Effects Table 13.3: Predicted OHL Noise Level from Single Conductor under Wet Weather Table 13.4: Assessment of OHL Operational Noise Table 13.5: Summary of Potential Operational Impacts of the Proposed

Development, Mitigation and Residual Impacts

Chapter 14 Schedule of Mitigation Table 14.1: Schedule of Mitigation Measures


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LT000022 Volume 2:

Table of Contents

VOLUME 2 MAIN REPORT – LIST OF FIGURES

Chapter 1 Introduction Figure 1.1: Location of Proposed Development

Chapter 2 Description of Development Figure 2.1: Limits of Deviation: OHL and Associated Works Figure 2.2: Limits of Deviation: OHL and Associated Works Figure 2.3: Limits of Deviation: OHL and Associated Works Figure 2.4: Limits of Deviation: OHL and Associated Works Figure 2.5: Limits of Deviation: OHL and Associated Works Figure 2.6: Indicative Schematic of Potential Underground Cable installation

Chapter 3 Environmental Impact Assessment Methodology Figure 3.1: Cumulative Developments

Chapter 4 Route Selection and Alternatives Figure 4.1: Alternative Corridors Figure 4.2: Alternative Routes Figure 4.3: Alternative Route Options Figure 4.4 : Post Consultation Variations Figure 4.5: Connection Option progressed for first technical assessment Figure 4.6: Alternative Mitigation Options

Chapter 6 Landscape and Visual Amenity Figure 6.1: Study Area Figure 6.2: Landscape Character Types Figure 6.3: Landscape Designations Figure 6.4: “Bare Ground” ZTV (OHL) overlaid with Viewpoints Figure 6.4.1: “Bare Ground” ZTV Underground cable construction overlaid with

Viewpoints Figure 6.5: “With Screening” ZTV (OHL) overlaid with Viewpoints Figure 6.5.1: “With Screening” ZTV Underground cable construction overlaid with

Viewpoints Figure 6.6: Viewpoint 1 - Existing View and Wireline Figure 6.6.1: Viewpoint 1 - Photowire Figure 6.6.2: Viewpoint 1 - Photomontage Figure 6.7: Viewpoint 2 - Existing View and Wireline Figure 6.7.1: Viewpoint 2 - Photowire Figure 6.7.2: Viewpoint 2 - Photomontage Figure 6.8: Viewpoint 3 - Existing View and Wireline Figure 6.8.1: Viewpoint 3 - Photowire Figure 6.8.2: Viewpoint 3 - Photomontage Figure 6.9: Viewpoint 4 - Existing View and Wireline Figure 6.9.1: Viewpoint 4 - Photowire Figure 6.9.2: Viewpoint 4 - Photomontage Figure 6.10: Viewpoint 5 - Existing View and Wireline Figure 6.10.1: Viewpoint 5 - Photowire


Gills Bay 132 kV


Figure 6.10.2: Viewpoint 5 - Photomontage Figure 6.11: Viewpoint 6 - Existing View and Wireline Figure 6.11.1: Viewpoint 6 - Photowire Figure 6.11.2: Viewpoint 6 - Photomontage Figure 6.12A: Viewpoint 7A - Existing View and Wireline Figure 6.12B: Viewpoint 7B- Existing View and Wireline Figure 6.12C: Viewpoint 7C - Existing View and Wireline Figure 6.12.1A: Viewpoint 7A - Photowire Figure 6.12.1B: Viewpoint 7B - Photowire Figure 6.12.1C: Viewpoint 7C - Photowire Figure 6.12.2A: Viewpoint 7A - Photomontage Figure 6.12.2B: Viewpoint 7B - Photomontage Figure 6.12.2C: Viewpoint 7C - Photomontage Figure 6.13A: Viewpoint 8A- Existing View and Wireline Figure 6.13B: Viewpoint 8B- Existing View and Wireline Figure 6.13C: Viewpoint 8C- Existing View and Wireline Figure 6.13D: Viewpoint 8D- Existing View and Wireline Figure 6.13.1A: Viewpoint 8A - Photowire Figure 6.13.1B: Viewpoint 8B - Photowire Figure 6.13.1C: Viewpoint 8C - Photowire Figure 6.13.1D: Viewpoint 8D - Photowire Figure 6.13.2A: Viewpoint 8A - Photomontage Figure 6.13.2B: Viewpoint 8B - Photomontage Figure 6.13.2C: Viewpoint 8C - Photomontage Figure 6.13.2 D: Viewpoint 8D - Photomontage Figure 6.14: Viewpoint 9 - Existing View and Wireline Figure 6.14.1: Viewpoint 9 - Photowire Figure 6.14.2: Viewpoint 9 - Photomontage Figure 6.15: Viewpoint 10 - Existing View and Wireline Figure 6.15.1: Viewpoint 10 - Photowire Figure 6.15.2: Viewpoint 10 - Photomontage Figure 6.16A: Viewpoint 11A - Existing View and Wireline Figure 6.16B: Viewpoint 11B - Existing View and Wireline Figure 6.16.1A: Viewpoint 11A - Photowire Figure 6.16.1B: Viewpoint 11B - Photowire Figure 6.16.2A: Viewpoint 11A - Photomontage Figure 6.16.2B: Viewpoint 11B - Photomontage Figure 6.17: Viewpoint 12 - Existing View and Wireline Figure 6.17.1: Viewpoint 12- Photowire Figure 6.17.2: Viewpoint 12 - Photomontage Figure 6.18: Viewpoint 13 - Existing View and Wireline Figure 6.18.1: Viewpoint 13 - Photowire Figure 6.18.2: Viewpoint 13 - Photomontage Figure 6.19: Viewpoint 14 - Existing View and Wireline Figure 6.19.1: Viewpoint 14 - Photowire Figure 6.19.2: Viewpoint 14 - Photomontage Figure 6.20: Viewpoint 15 - Existing View and Wireline Figure 6.20.1: Viewpoint 15 - Photowire Figure 6.21: Viewpoint 16 - Existing View and Wireline


LT000022 Volume 2:

Table of Contents

Figure 6.22: Viewpoint 17 - Existing View and Wireline Figure 6.23: Viewpoint 18 - Existing View and Wireline Figure 6.23.1: Viewpoint 18 - Photowire Figure 6.24: Viewpoint 19 - Existing View and Wireline Figure 6.25: Routes for Sequential Assessment Figure 6.26: Other Developments Within 30km

Chapter 7 Ecology Figure 7.1: Study Areas Figure 7.2: Designated Sites Figure 7.3a: Phase 1 Habitats - Section 1 - Thurso to Hill of Olrig Figure 7.3b: Phase 1 Habitats - Section 2- Hill of Olrig to Wester Olrig Figure 7.3c: Phase 1 Habitats - Section 3- Wester Olrig to Reaster Figure 7.3d: Phase 1 Habitats - Section 4- Reaster to Gills Bay Figure 7.4: NVC Target Notes and Groundwater Dependent Terrestrial

Ecosystems. Figure 7.5: Protected Species Survey Results

Chapter 8 Ornithology Figure 8.1: Vantage Point Locations with Viewsheds Figure 8.2: Ornithological Designated Sites Figure 8.3: White-fronted Goose Flights Proposed Development Figure 8.4: White-fronted Goose Flights on additional Vantage Point Surveys Figure 8.5a: White-fronted Goose Flights Caithness Lochs Figure 8.5b: White-fronted Goose Flights Caithness Lochs Figure 8.5c: White-fronted Goose Flights Caithness Lochs Figure 8.6: Greylag Goose Flights Proposed Development Figure 8.7: Greylag Goose Flights on additional Vantage Point Surveys Figure 8.8a: Greylag Goose Flights Caithness Lochs Figure 8.8b: Greylag Goose Flights Caithness Lochs Figure 8.8c: Greylag Goose Flights Caithness Lochs Figure 8.90: Greylag Goose Roaming Survey Figure 8.10: Whooper Swan Flights Proposed Development Figure 8.11: Whooper Swan Flights on additional Vantage Point Surveys Figure 8.12a: Whooper Swan Flights Caithness Lochs Figure 8.12b: Whooper Swan Flights Caithness Lochs Figure 8.12c: Whooper Swan Flights Caithness Lochs Figure 8.13: Whooper Swan Roaming Survey Figure 8.14: Short-eared Owl Flights Caithness Lochs Figure 8.15: Hen Harrier Flights Proposed Development Figure 8.16: Hen Harrier Flights on additional Vantage Point Surveys Figure 8.17a: Hen Harrier Flights Caithness Lochs Figure 8.17b: Hen Harrier Flights Caithness Lochs Figure 8.18: Hen Harrier Roaming Survey Figure 8.19: Merlin Flights Proposed Development Figure 8.20: Merlin Flights on additional Vantage Point Surveys Figure 8.21a: Merlin Flights Caithness Lochs Figure 8.22: Golden Plover Flights Proposed Development Figure 8.23: Golden Plover Flights on additional Vantage Point Surveys


Gills Bay 132 kV


Figure 8.24: Golden Plover Roaming Survey Figure 8.25: Wigeon Flights Proposed Development Figure 8.26: Wigeon Roaming Survey Figure 8.27: Peregrine Falcon Flights Proposed Development Figure 8.28: Peregrine Falcon Flights on additional Vantage Point Surveys Figure 8.29: Mute Swan Flights Proposed Development Figure 8.30: Mute Swan Flights Caithness Lochs Figure 8.31: Pink-footed Goose Flights Proposed Development Figure 8.32: Pink-footed Goose Flights on additional Vantage Point Surveys Figure 8.33a: Pink-footed Goose Flights Caithness Lochs Figure 8.33b: Pink-footed Goose Flights Caithness Lochs Figure 8.33c: Pink-footed Goose Flights Caithness Lochs Figure 8.34: Pink-footed Goose Roaming Survey Figure 8.35: Bean Goose Flights Proposed Development Figure 8.36: Bean Goose Flights Caithness Lochs Figure 8.37: Barnacle Goose Flights Proposed Development Figure 8.38: Teal Flights Proposed Development Figure 8.39: Teal Roaming Survey Figure 8.40: Mallard Flights Proposed Development Figure 8.41: Mallard Flights on additional Vantage Point Surveys Figure 8.42: Mallard Flights Caithness Lochs Figure 8.43: Mallard Roaming Survey Figure 8.44: Tufted Duck Flights Caithness Lochs Figure 8.45: Cormorant Flights on additional Vantage Point Surveys Figure 8.46: Cormorant Flights Caithness Lochs Figure 8.47: Grey Heron Flights Proposed Development Figure 8.48: Grey Heron Flights on additional Vantage Point Surveys Figure 8.49: Grey Heron Flights Caithness Lochs Figure 8.50: Grey Heron Roaming Survey Figure 8.51: Raptor Flights Proposed Development Figure 8.52a: Raptor Flights on additional Vantage Point Surveys Figure 8.52b: Raptor Flights on additional Vantage Point Surveys Figure 8.53: Raptor Roaming Survey Figure 8.54: Wader Flights Proposed Development Figure 8.55a: Wader Flights on additional Vantage Point Surveys Figure 8.55b: Wader Flights on additional Vantage Point Surveys Figure 8.56: Wader Flights Caithness Lochs Figure 8.57: Wader Roaming Survey Figure 8.58: Great Black backed Gull Flights Proposed Development Figure 8.59: Great Black Backed Gull Flights Roaming Survey Figure 8.60: Raven Flights Proposed Development Figure 8.61a: Breeding Bird Survey Figure 8.61b: Breeding Bird Survey Figure 8.61c: Breeding Bird Survey Figure 8.61d: Breeding Bird Survey Figure 8.61e: Breeding Bird Survey Figure 8.61f: Breeding Bird Survey Figure 8.62a: Wader Breeding Bird Survey Figure 8.62b: Wader Breeding Bird Survey


LT000022 Volume 2:

Table of Contents

Figure 8.62c: Wader Breeding Bird Survey Figure 8.62d: Wader Breeding Bird Survey Figure 8.62e: Wader Breeding Bird Survey Figure 8.62f: Wader Breeding Bird Survey

Chapter 9 Archaeology and Cultural Heritage Figure 9.1a: Cultural Heritage Constraints Figure 9.1b: Cultural Heritage Constraints Figure 9.1c: Cultural Heritage Constraints Figure 9.1d: Cultural Heritage Constraints Figure 9.1e: Cultural Heritage Constraints Figure 9.1f: Cultural Heritage Constraints Figure 9.1g: Cultural Heritage Constraints Figure 9.1h: Cultural Heritage Constraints Figure 9.2: Cultural Heritage: Zone of Theoretical Visibility Figure 9.3: Wireline View of Proposed Development from Earney Hillock

Chambered Cairn Figure 9.4: Wireline View of Proposed Development from Earl's Cairn Chambered

Cairn Figure 9.5: Wireline View of Proposed Development from Stemster Cairn

Chambered Cairn Figure 9.6: Wireline View of Proposed Development from Tulloch of Shalmstry

Broch

Chapter 10 Geology, Hydrogeology and Hydrology Figure 10.1: Study Area and Surface Water Features Figure 10.2: Associated Works and Watercourse Crossings Figure 10.3: Private Water Supplies and CAR Licenses

Chapter 12 Traffic and Transport Figure 12.1: Local Road Network Figure 12.2: Traffic Survey Locations Figure 12.3: Potential Access Routes

Chapter 13 Noise Figure 13.1: Location of Noise Sensitive Receptors Figure 13.2: Location of Noise Sensitive Receptors Figure 13.3: Location of Noise Sensitive Receptors Figure 13.4: Location of Noise Sensitive Receptors Figure 13.5: Assumed Background Noise Levels Resulting from Rain (embedded

within text)


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LT000022 Abbreviations – Volume 2

VOLUME 2 MAIN REPORT – ABBREVIATIONS

ACIEEM Associate Member of the Chartered Institute of Ecology and Environmental Management

ACoW Archaeological Clerk of Works

AOD Above Ordnance Datum

BAP Biodiversity Action Plan

BGS British Geological Survey

BPP Badger Protection Plan

BSI British Standards Institution

BTO British Trust for Ornithology

CAA Civil Aviation Authority

CAR Controlled Activity Regulation

CaSplan Caithness and Sutherland Area Local Development Plan

CBAP Caithness Biodiversity Action Plan

CBD Convention on Biological Diversity

CDM Construction Design and Management

CEMD Construction Environmental Management Document

CIEEM Chartered Institute of Ecology and Environmental Management

CLP Caithness Local Plan

CRA Collision Risk Assessment

DECC Department of Energy and Climate Change

DMP Drainage Management Plan

DTM Digital Terrain Model

ECDU Scottish Government Energy Consents and Deployment Unit

EcIA Ecological Impact Assessment

ECoW Environmental Clerk of Works

EIA Environmental Impact Assessment

EMF Electromagnetic Field

EMP Environmental Management Plan

EN5 Electricity Networks Infrastructure

ENEL Ente Nazionale per L’Energia Elettrica

EPS Extended Phase 1 Habitat Survey (European Protected Species)

EQS Environmental Quality Standards


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Abbreviations – Volume 2 LT000022

ES Environmental Statement

FC Forestry Commission

FCD Field Capacity Day

FCE Forestry Civil Engineering

FCS Favourable Conservation Status

FRA Flood Risk Assessment

GDL Gardens and Designed Landscapes

GES Government Economic Strategy

GIS Geographic Information System

GPS Global Positioning System

GVLIA 3 Guidelines for Landscape and Visual Impact Assessment 3rd Edition

GWDTE Groundwater Dependent Terrestrial Ecosystems

GWFG Greenland Greater White-fronted Goose

HBAP Highland Biodiversity Plan

HER The Highland Council Historic Environment Record

HET The Highland Council Historic Environment Team

HGV Heavy Goods Vehicle

HLAMap Historic Land-Use Assessment Data for Scotland

HPA Health Protection Agency

HS Historic Scotland

HVTRC High Voltage Transmission Research Centre

HwLDP Highland-wide Local Development Plan

ICNRIP International Commission on Non-Ionising Radiation Protection

IPCC Intergovernmental Panel on Climate Change

LCA Landscape Character Assessment

LCA Land Capability for Agriculture

LCC Land Capability Classification

LCT Landscape Character Type

LNR Local Nature Reserve

LOD Limits of Deviation

LVIA Landscape and Visual Impact Assessment

MCIEEM Member of the Chartered Institute of Ecology and Environmental Management

MCIWEM or C.WEM

Chartered Member of the Chartered Institute of Water and Environmental Management


LT000022 Abbreviations – Volume 2

NBN National Biodiversity Network

NCN National Cycle Network

NHZ Natural Heritage Zone

NNR National Nature Reserve

NPF3 National Planning Framework 3 (Scotland)

NSR Noise sensitive receptors

NTS Non-Technical Summary

NVC National Vegetation Classification

OHL Overhead Line

ORS Old Red Sandstone

PAN Planning Advice Note

PMO Planning Monitoring Officer

PPG Pollution Prevention Guidance

PWS Private Water Supply

RBMP River Basin Management Plan

RCAHMS Royal Commission on the Ancient and Historical Monuments of Scotland

RFI Radio Frequency Interference

RSPB Royal Society for the Protection of Birds

SAC Special Areas of Conservation

SEC Sealing End Compound

SEPA Scottish Environment Protection Agency

SG Supplementary Guidance

SHEP Scottish Historic Environment Policy

SLA Special Landscape Area

SM Scheduled Monument

SNH Scottish Natural Heritage

SOHCC Species Of High Conservation Concern

SOMCC Species of Medium Conservation Concern

SPAD The Scottish Palaeoecological Database

SPP Scottish Planning Policy

SpPP Species Protection Plan

SSSI Site of Special Scientific Interest

SUDS Sustainable Drainage Systems

THC The Highland Council


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Abbreviations – Volume 2 LT000022

TR Technical report

TRL Transport Research Laboratory

UKTAG UK Technical Advisory Group

VP Vantage Point

WCA The Wildlife and Countryside Act

WEWS Water Environment and Water

WFD Water Framework Directive

WSI Written Scheme of Investigation

ZTV Zone of Theoretical Visibility


LT000022 1-1 Chapter 1:

Introduction

1 INTRODUCTION

1.1 Introduction

1.1.1 Scottish Hydro Electric Transmission plc (hereafter referred to as ‘the Applicant’) is a wholly owned subsidiary of SSE plc. It proposes to submit an application for consent under section 37 (s37), under the Electricity Act 1989 (including deemed consent under the Town and Country Planning (Scotland) Act 1997 where required), for the construction of a new double circuit 132 kV transmission connection, between a new substation at Thurso South (Thurso South substation) (planning consent granted on 19th September 2013, 13/000594/FUL) and a proposed new substation at Phillips Mains, near Gills Bay (Gills Bay substation1). The project is referred to as the Gills Bay 132 kV (and hereafter as the ‘Proposed Development’).

1.1.2 The Proposed Development comprises approximately 13 km of overhead line (OHL) supported by lattice steel towers; approximately 3 km of underground cable on the approach to Thurso South substation and approximately 7 km of underground cable from Reaster to Gills Bay Substation.

1.1.3 Deemed consent is sought for the underground cable elements of the Proposed Development and Sealing End Compounds (SECs) under s57 of the Town and Country Planning (Scotland) Act 1997 along with associated works (see section 2.2), potential impacts of which have been evaluated and documented within each Environmental Statement (ES) technical assessment (separately from the S37 development) for completeness.

1.1.4 The location of the Proposed Development is shown in Figure 1.1.

1.2 Development Need

1.2.1 Analysis of the existing transmission network in the north of Scotland identified the need for increased network capacity to facilitate the transmission of renewable generation projects north of Beauly including onshore/offshore wind and marine and tidal generation. This increase in network capacity can only be achieved by developing the transmission network in the North of Scotland. The Proposed Development is part of this expansion.

1.3 Environmental Impact Assessment (EIA) Screening

1.3.1 The Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2000 (as amended in 2008) - hereafter referred to as the “EIA regulations” contain two schedules. Schedule 1 lists projects where EIA is mandatory. Schedule 2 lists projects where EIA may be required ’where proposed development is considered likely to give rise to significant effects on the environment by virtue of factors such as its nature, size or location’.

1.3.2 The OHL elements of the Proposed Development is of a type listed in Schedule 2(d), ‘an electric line installed above ground with a voltage of 132 kV or more, the

1 The Gills Bay substation is subject to a planning application to The Highland Council. The substation has been screened as

non EIA development [12/02137/SCRE). The application will be supported by a non-statutory Environmental Appraisal, which

is also appended to this ES for information. It does not form part of the EIA in support of the s37 application.


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Chapter 1: Introduction 1-2 LT000022

installation of which (or the keeping installed of which) will require a section 37 consent, but which is not Schedule 1 development and where EIA may be required where the proposal is considered likely to given rise to significant effects on the environment by virtue of factors such as its nature size and location’.

1.3.3 Whilst the remaining elements of the Proposed Development (underground cabling and associated works) do not explicitly fall within the requirements of the EIA regulations, the Applicant has, for completeness carried out a full appraisal of these elements of the Proposed Development and documented that appraisal within this ES.

1.4 Contents of the Environmental Statement

1.4.1 The required content of the ES is set out in Schedule 4 of the EIA Regulations. Technical Appendix 1.1 presents these requirements and indicates where in this ES the requirements have been met.

1.5 Structure of the Environmental Statement

1.5.1 The ES comprises four volumes as follows:

Volume 1: Non-Technical Summary, summarises the main elements of the Proposed Development and the significant environmental impacts identified in the EIA.

Volume 2: the Main Report details the main findings of the EIA and is structured as follows:

- Chapter 1: Introduction;

- Chapter 2: Description of Development;

- Chapter 3: EIA Methodology;

- Chapter 4: Alternatives;

- Chapter 5: Planning and Policy Context;

- Chapter 6: Landscape and Visual Impact Assessment;

- Chapter 7: Ecology and Nature Conservation;

- Chapter 8: Ornithology;

- Chapter 9: Cultural Heritage and Archaeology;

- Chapter 10 Geology, Hydrogeology and Hydrology;

- Chapter 11: Soils, Landuse and Agriculture;

- Chapter 12: Traffic and Transport;

- Chapter 13: Noise; and

- Chapter 14: Schedule of Mitigation.

Volume 3: Figures includes all supporting graphics to the ES Chapters.

Volume 4: Appendices, details specialist reports, data and information relevant to the ES chapters.


LT000022 1-3 Chapter 1:

Introduction

1.5.2 Additional documentation that will be submitted in support of the s37 application includes:

Application forms;

Planning Application figures showing the Proposed Development; and

Planning Statement.

1.6 The Project Team

1.6.1 The Applicant has appointed a design and technical team to assist in the development of the application and has drawn on the expertise of various specialists to carry out the assessments.

1.7 Notifications

1.7.1 Notice will be served to the relevant planning authority, in this case The Highland Council, of the application to the Scottish Ministers for consent under section 37 of the Electricity Act 1989.

1.7.2 At the same time and in accordance with the Electricity Applications for Consent Regulations 1990, and section 9 of the Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2000, the application and the ES will be advertised in the following local newspapers: John O’Groat Journal; and the Caithness Courier. It will also be advertised in the following regional newspapers: Edinburgh Gazette; and the Scotsman.

1.7.3 The s37 application, including the ES and associated documents will be available for viewing at the following locations:

Thurso Service Point

Council Offices

Rotterdam Street

Thurso

KW14 8AB

Government Buildings

Girnigoe Street

Wick

KW1 4HW

Caithness Horizons

High Street

Thurso

Caithness

KW14 8AJ

Mey Village Hall

Mey

Caithness

KW14 8XH

1.7.4 Electronic versions of the application, including the ES will be available to download from the Applicant’s website at https://www.ssepd.co.uk/GillsBay/.


Gills Bay 132 kV

Chapter 1: Introduction 1-4 LT000022

1.7.6 This document is available in other formats if required – for details and costings, please contact:

Lisa Marchi SHE Transmission Community Liaison Manager Scottish Hydro Electric Transmission plc 10 Henderson Road Inverness IV1 1SN


LT000022 2-1 Chapter 2:

Description of Development

2 DESCRIPTION OF DEVELOPMENT

2.1 Introduction

2.1.1 This chapter provides a description of the main elements of the Proposed Development.

2.2 The Proposed Development

2.2.1 The Proposed Development will comprise (from west to east):

approximately 3 km of underground cable from Thurso South substation to a Sealing End Compound (SEC) at Weydale1;

approximately 13 km of 132 kV OHL, supported by lattice steel towers, between the SEC at Weydale and a further SEC north of Reaster; and

approximately 7 km of underground cable from the SEC at Reaster to the proposed substation at Gills Bay.

2.2.2 The alignment followed by the Proposed Development and the proposed position of the SECs and steel lattice towers has been determined on the basis of the environmental assessment reported within the ES, together with an engineering analysis of ground conditions and suitability based on desk studies and site walkovers. Investigation of sub-surface and geotechnical conditions at proposed tower locations has not been undertaken. It is possible therefore that individual tower locations might alter following geotechnical investigation (referred to as micro siting). To strike a balance between providing certainty between the location of the Proposed Development and any environmental impacts, and the need for some flexibility over individual tower locations, Limits of Deviation (LOD) have been defined (see section 2.4 below) within which the Proposed Development would be constructed. No towers or working areas would be located outside the LOD described. Certain associated works will also be required including:

works associated with establishing access for the construction and maintenance of the OHL and underground cable. This may include:

vegetation clearance;

upgrading of existing or establishment of new junction bell-mouths and access tracks; and

road and other infrastructure (bridges, culverts etc.) alterations.

felling of an area of woodland to accommodate the Proposed Development, on the approach to the proposed Gills Bay substation; and

temporary measures to protect road and water crossings during construction (scaffolding etc.).

2.2.3 These associated works are described in more detail in section 2.5.

1 The underground cable elements of the Proposed Development will be progressed as deemed consent under the s37

application. However they are considered within this ES for completeness. The SECs would also be progressed as deemed consent.


Gills Bay 132 kV

Chapter 2: Description of Development 2-2 LT000022

2.3 Limits of Deviation

2.3.1 Consideration was given to the following principles in defining the LOD for the Proposed Development:

presumption towards the narrowest possible LOD whilst providing flexibility for micro-siting;

presumption towards avoiding sensitive environmental features2; and

presumption towards avoiding residential properties3.

2.3.2 The LOD is illustrated on Figures 2.1 to 2.5.

2.4 OHL Design

2.4.1 The s37 application identifies the anticipated tower locations (subject to micro siting adjustment see section 2.2) along the Proposed Development. The following additional OHL design information has been assumed for the purposes of the EIA.

Lattice Steel Towers

2.4.2 The towers to be used for the Proposed Development will be constructed from fabricated galvanised steel and will be grey in colour. The Proposed Development will use a 'L7C' series of lattice steel tower (as shown in Photo 2.1 below), which can vary in height, however the typical tower height will be 30 m4. Three types of tower are likely to be used within the Proposed Development as shown on Photo 2.1 and Plate 2.1 below. These are described below:

suspension towers: These are used for straight sections of OHL where there is no need to terminate the conductor. It is currently anticipated that approximately 42 suspension towers will be required;

angle/tension towers: These are used either in-line, where there is a need to terminate the conductors, and/or where there is a need to change the orientation of the OHL. It is currently anticipated that approximately 10 angle towers will be required; and

terminal towers: These are used in each of the SECs.

2.4.3 It is currently anticipated that a total of 52 towers will be constructed. Locations are provided in Technical Appendix 2.2.

2 No specific separation distance has been applied, rather each feature has been considered on a case by case basis. 3 Whilst no prescriptive separation distance has been adopted a 100 m separation has been sought where ever possible

around residential properties based on the noise assessment predicting audible noise can propagate up to 50 m in wet conditions (refer to chapter 13 for full details).

4 It is anticipated that tower height range will be between minimum height of 23 m and not more than 40 m in height, and the typical tower height will be 30 m.


LT000022 2-3 Chapter 2:


Plate 2.1: L7 Line Tower as proposed5

5 National Grid – Technical Guidance Notes (NG TGN(E) 166


Gills Bay 132 kV


Plate 2.2: Inidcative Tower Heights of the L7 Towers


LT000022 2-5 Chapter 2:


Conductors and Span Length

2.4.4 Towers will carry two circuits, each with three conductors supported from either, glass, porcelain, or composite insulators attached to the horizontal cross arms on both sides of each lattice steel tower. An earth wire with a fibre optic core will be suspended between tower peaks, above the conductors.

2.4.5 The span length (distance between towers) will vary depending on topography, and land usage; however the average spacing between individual towers is likely to be in the region of 250 m.

Tower Foundations

2.4.6 Different approaches to forming foundations may be used, subject to ground conditions at each tower location. These are likely to comprise:

spread type e.g. concrete pad and chimney;

piled type e.g. driven concrete, tube and micro pile; or

augered.

2.4.7 Foundation types and designs for each tower will be confirmed following detailed geotechnical investigation at each tower position, although it is currently anticipated that the majority of tower foundations are likely to be of a concrete pad and chimney type. Dimensions of each foundation will be confirmed following micrositing. For the purposes of this assessment however it has been assumed that each foundation would be approximately 50 cm deep, buried to depths estimated up to 2.5 m below ground level (bgl) although extending up to 4 m depth where ground conditions require. They would extend over an area suitable to deliver the loading characteristics required (which would be a function of the underlying ground conditions and the weight of the structures to be supported).

2.4.8 Piled foundations may be required where low strength ground conditions exist, particularly where peat is encountered at over 1 m depth.

2.4.9 For the purposes of the ES it has been assumed that individual tower foundations and associated construction activities will require a working area of approximately 2500 m2 (50 m x 50 m) around each individual tower location. The exact dimensions of the working area around each tower will be confirmed following micrositing. All working areas will be located within the LOD as shown in Figures 2.1 to 2.5. Construction sites for each tower will be fenced as appropriate after discussions with the landowner, ahead of construction commencing to ensure protection to livestock and the general public.

Sealing End Compounds

2.4.10 Two sealing end compounds (SECs) will be required. SECs are used to connect the OHL to the underground cable sections of the route. These would be progressed as deemed consent under the S37 application.

2.4.11 The SECs will be approximately 40 m x 40 m and will be securely fenced. A typical SEC is shown in Photo 2.1 below:


Gills Bay 132 kV


Photo 2.1: Typical SEC6

2.5 Underground Cable Installation

2.5.1 Various methods are available for the installation of underground installation works ranging from localised cable ploughing methods to cable trenching. For the purposes of this ES, the assessment has been carried out on the basis that cable trenching methodology will be employed, but if it is possible to use a less intrusive method such as cable ploughing then the impacts will be less than those which are assessed.

2.5.2 The schematics set out within Figure 2.6 illustrate the likely sequence of events for cable installation using trenching methodology. Anticipated working width has been assumed to be 30 m with a trench depth of approximately 1.4 m. The width of the cable trench within the working width will be determined by the cable arrangement and the required spacing between cables.

2.6 Construction and Phasing

2.6.1 Table 2.1 provides an indicative sequence for OHL construction.

Table 2.1 Indicative Construction Phasing

Phase Description Duration

Phase 1 Distribution Network diversions and undergrounding (not part of the s37 application).

December 16 – March 17

Est 4 months.

Phase 2 Including Access Development (Phase 2a) and other enabling works (Phase 2b) including forestry clearance and establishment of construction compound(s) etc. Phase 2b will also include delivery of other relevant commitments e.g. pre-construction environmental surveys, as set out Construction Environmental Management Document (CEMD).

December 16 to June 17

Est. 7 months

Phase 3 Installation of tower foundations. March 17 – April 18

Est. 13 months

6 Provided to Ramboll Environ by the SHET Environmental Project Manager


LT000022 2-7 Chapter 2:


Table 2.1 Indicative Construction Phasing

Phase Description Duration

Phase 4 Erection of towers. August 17 –April 18

Est. 9 months

Phase 5 Conductor stringing (including construction of temporary scaffolding).

March 18 – June 18

Est. 4 months

Phase 6 Check, Erect inspections and OHL commissioning. June 18 to Feb 19

Est. 8month

2.6.2 Indicative phasing proposals remain subject to confirmation and verification following appointment of the Principal Contractor. The delivery of each phase will overlap along the length of the Proposed Development. It is anticipated that the construction programme (Phases 1 to 6) will last approximately 27 months and take place in the period between December 2016 and Feb 2019.

2.6.3 The exact timing of works will have regard to seasonal restrictions in some sections where required by ecological or land owner constraints. Construction works may be more limited during winter months.

Phase 1: Alterations to Distribution Network

2.6.4 Works will be required to existing 33 kV and 11 kV distribution network infrastructure which are crossed by the OHL LOD. It is anticipated that these distribution network assets will be undergrounded to make way for the Proposed Development and can be carried out under Permitted Development rights.

Phase 2a: Enabling Works - Access Strategy

2.6.5 Detailed access proposals will be developed by the Principal Contractor (yet to be appointed). In general, based on desk study analysis and preliminary walkover inspections, access will be established through a combination of:

upgrade to existing tracks;

installation of temporary new tracks;

Installation of permanent floating stone roads7; and

Installation of permanent new roads.

2.6.6 It is anticipated that the majority of access will be achieved through upgrade of existing and installation of temporary new tracks. Floating stone road or trackway panel construction would be installed, in sensitive areas such as over peat.

2.6.7 Approximately 17.5 km of access track will be required to be upgraded or installed. This will include alterations to or formations of approximately 23 bellmouths/junctions within the existing road network. Table 2.2 provides a schedule describing where these accesses are likely to connect with the adopted road network. These are also shown on Figure 2.1 to 2.5. Deemed consent is sought for these access tracks and access points.

7 Floating stone road construction typical comprises a layer of geotextile overlaid by approximately 50 cm of crushed

concrete/hardcore.


Gills Bay 132 kV


Table 2.2: Schedule of Likely Access and Egress Points onto Adopted Road Network.

Section Location Description NGR

A to B Upgrade to existing track running south from existing road at Weydale.

ND146 645

A to B Temporary road running south east and then east from existing road at South Weydale

ND 147 637

B to C Temporary road running north west from existing road to the east of Achingills and Marl Moss.

ND165 635

B to C Upgrade to existing track running south east from existing road to the east of Achingills and Marl Moss.

ND166 636

B to C Temporary road running south west and then south southeast at Hilliclay

ND 169 693

C to D Upgrade to existing track to the east of woodland at Fryster. ND180 639

C to D Temporary road running south west and then splits to two separate tracks to south east and west which consist upgrades to existing tracks parallel to existing road, opposite school house, south of Fryster.

ND186 632

C to D Upgrade to existing track running south west from existing road, south east of school house, Fryster.

ND187 632

C to D Temporary road south east, just to south of Bishop’s Hill ND 192 631

C to D Temporary roads that split into two separate tracks both running parallel to the existing track at the east of Bishop’s Hill.

ND 196 628

C to E Upgrade path running east at Ha’ of Duran ND 198 634

D to E Temporary road running north northwest at the east of Ha’ of Duran

ND 205 632

D to E Temporary road running south west, parallel to the existing track, south of Hoy

ND 208 635

D to E Temporary road running north east, parallel to the existing track, south of Hoy

ND 208 637

D to E Temporary road running south east from existing road at Hoy (southern edge).

ND210 639

D to E Temporary road running east from existing road mid-way between Hoy and Wester Olrig.

ND213 644

E to F Temporary road running north east from B876. ND220 648

G to H Temporary road running west north west from existing road at Round hill. Moss of Tain.

ND228 653

G to H Temporary road running east south east from existing road at Round hill, Moss of Tain.

ND228 653

H to I Temporary road running north west from the Hunster to Easter road, on edge of Moss of Greenland.

ND249 649


LT000022 2-9 Chapter 2:


Table 2.2: Schedule of Likely Access and Egress Points onto Adopted Road Network.

Section Location Description NGR

H to I Floating stone road running north northeast from the Hunster to Easter road, onto Moss of Greenland.

ND250 650

I to J Temporary road running west south west at the north west of Reaster

ND 256 658

I to J Temporary road running east and then north east at the north of Reaster

ND 255 651

Phase 2b: Other Enabling Works

CEMD requirements

2.6.8 Section 2.8 to 2.10 and Technical Appendix 2.1 sets out details of the anticipated content of the Construction Environmental Management Document (CEMD), which will set out the high level policies, procedures and controls to be adopted to control and/or mitigate potential environmental impacts during construction. Prior to construction commencing, this will be supplemented by a more detailed Construction Environmental Management Plan (CEMP) which will be produced by the lead contractor setting out how the requirements of the CEMD will be delivered.

Forestry Clearance

2.6.9 The current route selection and LOD for the OHL largely avoids area of woodlands, with the exception of a small shelterbelt at Wester Olrig (fig. 2.3: Proposed OHL and Cable Route; LOD sub section D to E). This conifer woodland lies to the leaward side of the OHL and felling of the adjacent wind firm edge (the edge of woodland able to withstand strong winds and resist windthrow (blowdown), wind-rocking, and major breakage) should be avoided. Crown reduction and micro-siting of towers within the LOD will be sufficient to remove the need to fell trees in this location.

2.6.10 Tree removal will be required through the semi-mature conifer woodland to enable the cable laying within the LOD sub section L to M through Hollandmey plantation (Figure 2.5). Good use of the LOD will minimise this removal to protect wind firm edges.

Construction Depot

2.6.11 It is currently anticipated that a single main construction depot will be required, the location of which will be confirmed by the Principal Contractor. Temporary construction staging locations may be required along the LOD, the location of which will be determined through ongoing design works. Any location of the construction depot outside the Associated Works LOD will be the subject a separate planning application8.

Phase 3: Tower Foundations

2.6.12 Where encountered, top soil (including peat) will be stripped from the tower working area to allow installation of tower erection pad(s) as necessary in order to

8 Under Town and Country Planning requirements


Gills Bay 132 kV


accommodate construction plant. Tower foundations will be excavated to approximately 2.5 - 4 m, depending on the foundation type. Concrete is likely to be brought to site ready-mixed with no requirement for concrete batching at individual tower locations. Once the concrete has been cast and set, the excavation will be backfilled, using the original excavated material where possible.

2.6.13 It is anticipated that formation of each tower foundation will take an approximate 4 week period. Photo 2.2 provides and illustrative image of tower foundation construction.

Photo 2.2 Illustrative Image of Tower Foundation Construction

Phase 4: Tower Construction

2.6.14 Tower construction can commence two weeks after the foundations have been cast, subject to weather conditions and concrete curing rates. Tower steelwork would be delivered to each tower construction site either as individual steel members or as prefabricated panels, depending on the method of installation and the available access.

Phase 5: Conductor Stringing

Temporary Construction Scaffolds

2.6.15 Prior to stringing the conductors, temporary protection measures, normally netted scaffolds) will be required across public roads and existing access tracks. Photo 2.3 provides an illustrative image of temporary scaffolding.


LT000022 2-11 Chapter 2:


Photo 2.3: Illustrative Image of Temporary Construction Scaffolds.

Conductor Stringing

2.6.16 Conductor stringing equipment (i.e. winches, tensioners and ancillary equipment) are set out at either end of pre-selected sections of the OHL.

2.6.17 Pilot wires will be pulled through the section to be strung. These will be hung in blocks (wheels) at each suspension tower in the section and connected to a winch and tensioner at the respective end of the section. The winch, in conjunction with the tensioner is used to pull the pilot wires which are connected to the conductor at the tensioner end. The conductor is pulled via the pilot wires through the section and under controlled tension to avoid contact with the ground and any under-running obstacles including protection scaffolds. Once the conductor has been strung between the ends of the section it is then tensioned to provide the necessary sag and then permanently clamped at each tower.

Phase 6: OHL Commissioning

2.6.18 The OHL and support towers will then be subject to an inspection and snagging process. This allows the Contractor and the Applicant to check that the works have been built to specification and are fit to energise. The circuits will then be energised from the substations and go through a commissioning procedure for the switchgear, communications and protection controls through the substations at Gills Bay and Thurso South.

2.7 Reinstatement

2.7.1 Following commissioning of the Proposed Development, all construction sites will be reinstated. Reinstatement will form part of the contract obligations for the Principal Contractor and will include the removal of all temporary access tracks, all work sites around the tower locations and the re-vegetation of all construction compounds etc.

2.7.2 The following principles will inform the approach to reinstatement of all sites:

best practice (as described within Chapter 11: Soils, Land Use and Agriculture) will be followed for reinstatement of all sites;

reinstatement plans will be detailed in the Construction Environmental Management Document (CEMD) (see Technical Appendix 2.1);


Gills Bay 132 kV


reinstatement plans will take account of any identified important habitat and species locations and archaeological sites;

all soils and peat to be removed will be stored appropriately (as described within Chapter 11) and replaced on site as soon as construction allows;

reinstatement will seek to successfully integrate the site with surrounding land uses and habitats;

the ground will be graded to fit with natural contours;

drainage will be made good;

natural regeneration of habitats will be promoted in preference to reseeding. If natural re-vegetation is unsuccessfully then re-seeding may take place;

opportunities to deliver local biodiversity enhancements will be identified by the Applicant, advised by an Environmental Clerk of Works;

any required replanting will be undertaken at appropriate times of the year and with the agreement of landowners; and

tree planting will generally not be carried out within the proximity of the new OHL unless suitable species or characteristics of the terrain can ensure continued long term safe operation of the OHL infrastructure.

Reinstatement of Access Tracks

2.7.3 Reinstatement would involve replacement of topsoil, grading and installation of drainage as required. Graded areas would be allowed to vegetate naturally, although some seeding may be required to stabilise sites.

Reinstatement of Tower Sites

2.7.4 Topsoil will be stored within the working area for each tower during construction. Subsoils removed to enable the construction of the foundations will be temporarily stockpiled in separate bunds within the working area. Once the foundations of each tower have been installed the excavated material will be replaced and compacted any surplus material will be graded around the working area prior to replacement and regrading of topsoil.

2.7.5 Each site will be allowed to re-vegetate naturally where ever possible.

Reinstatement of Construction Depot(s)

2.7.6 Construction depot site(s) will be made good at the end of construction with all buildings and materials removed and soils appropriately reinstated.

2.8 Construction Employment and Hours of Work

2.8.1 Employment will be the responsibility of the Principal Contractor but the Applicant would seek to promote the use of local employment, where ever practicable. The Applicant encourages the Principal Contractor to make use of suitable labour and resources from areas local to the location of the works.

2.8.2 The Applicant also takes community responsibilities seriously. The delivery of a major programme of capital investment in Scotland provides the opportunity for the Applicant and its supply chain to create a lasting legacy to local communities.


LT000022 2-13 Chapter 2:


2.8.3 It is envisaged that there will be a number of separate teams working at the same time at different locations within the LOD. The resource levels will be dependent on the final construction sequence and will be determined by the Principal Contractor.

2.8.4 Construction working is likely to be during daytime periods only. Working hours are currently anticipated between approximately 07.00 to 19.00 in summer and 07.30 to 17.00 (or within daylight hours) in winter Monday to Saturday. Any out of hours working would be agreed in advance with The Highland Council (THC).

2.9 Construction Traffic

2.9.1 The construction will give rise to regular, but low numbers of staff transport movements, with small work crews travelling to work site areas. It is anticipated that the Principal Contractor will identify a single main compound area, with a safe area for parking away from the public highway.

2.9.2 Vehicle movements will be required to construct new or upgraded access roads; deliver the foundation and tower components and conductor materials to site; deliver and collect materials and construction plant from the main site compound and to individual tower locations.

2.9.3 Table 2.3 below provides an indicative summary of the total anticipated traffic movements associated with construction of the Proposed Development, broken down by Phases.

Table 2.3: Summary of Predicted Construction Traffic Generation

Phase Car & Lights

OGV 19 OGV 2 Total

Overhead Line

Phase 1: Distribution network alterations – NOT part of Section 37 application

Phase 2: Enabling Works 60 210 8115 8385

Phase 3: Installation of Foundations 58 408 122 588

Phase 4 : Installation of Towers 65 234 117 416

Phase 5 : Conductor Stringing 64 174 126 364

Phase 6 : OHL Commissioning 30 0 0 30

Phase 7 : Reinstatement 0 55 0 55

Underground Cable

Phase 1 : Enabling Works (including access track construction)

1647 108 252 2007

Phase 2 : Construction 9283 2868 16315 28466

9 As described in Chapter 12; Traffic & Transport (Section 12.5), the following descriptions are used: Lights – this classification covers light goods vehicles (up to 3.5 tonne) and cars with trailers/caravans; Other goods vehicles – Class 1 (OGV1) & buses; this classifications covers smaller commercial vehicles between 3.5 and 7.5

tonnes and includes rigid 2 and 3 axle trucks and articulated trucks up to 3 axles as well as buses and coaches; and Other Goods Vehicles – Class 2 (OGV2); this classification covers all HGVs with four or more axles.


Gills Bay 132 kV


2.9.4 Technical Appendix 12.1 contains further information relating to anticipated traffic movements during construction.

2.10 Construction Management

2.10.1 All construction activities will be undertaken in accordance with a Construction Environmental Management Document (CEMD) which will define specific methods for environmental survey, monitoring and management throughout construction.

2.10.2 Further detail of anticipated content and scope of the CEMD is set out within Technical Appendix 2.1.

2.11 Operation and Management of the Transmission Connection

Life of the Project

2.11.1 Insulators and conductors can be anticipated to be replaced after approximately 40 years operation. Towers may be painted every 15 to 20 years.

Maintenance Programme

2.11.2 Maintenance activities will include regular line and tower inspections to identify any significant deterioration of components, so that they can be replaced. From time to time, inclement weather, storms or lightning may cause damage, either to the insulators or the conductors. If conductors are damaged, short sections may have to be replaced.

2.11.3 No general maintenance of the underground cable is required. If there is a fault with the cable, excavation will be required to allow the cable to be exposed and repaired quickly and safely.

Residues and Emissions

2.11.4 The EIA Regulations require that the ES provides an estimate, by type and quantity of expected residues and emissions (water, air and soil pollution, noise, vibration, light, heat, radiation etc.) resulting from the operation of the Proposed Development.

2.11.5 Once in operation, the Proposed Development is not anticipated to give rise to any residues and few emissions. There will be no activity associated with the operation of the Proposed Development that will give rise to air or soil pollution. There will be no vibration, light or significant heat from the OHL.

Electrical and Magnetic Fields

2.11.6 Electromagnetic fields (EMFs) arise from electric charges. They include static fields such as the Earth's magnetic field and fields from electrostatic charges, electric and magnetic fields from the electricity supply at power frequencies (50 Hz in the UK), such as overhead transmission lines and underground cables, through to radio waves from TV, radio and mobile phones, radar and satellite communications (3 kHz to 300 GHz). Electric and magnetic fields are common in the home and arise from power supplies (domestic ring main), and appliances. Fields vary in intensity from those associated with minor appliances such as lamps, to televisions and microwave cookers.


LT000022 2-15 Chapter 2:


2.11.7 The UK Health Protection Agency (HPA) is the government body responsible for policy and guidance on EMF. Exposure guidelines have been developed by the International Commission on Non-Ionising Radiation Protection (ICNRIP) to ensure protection of human health in different situations, occupational exposure and public exposure, which have been adopted by the HPA for application in the UK10 . The electric and magnetic field strengths for a 132 kV OHL of the type proposed here have been predicted11. Table 2.4 below presents these values within the context of typical values; ICNRIP exposure guidelines; and field strengths typical in most domestic situations12.

Table 2.4 Predicted EMF, Typical EMF and UK Exposure Guidelines

Source Electric Field (kV/m) Magnetic Field (uT13)

ICNRIP Public Exposure Guideline (1998)14

5 100

Directly beneath OHL

25 m from OHL

100 m from OHL

Directly beneath OHL

25 m from OHL

100 m from OHL

Predicted field – Proposed Development (132 kV OHL)11

2 0.2 26.6 15

Typical field – 132 kV OHL16 1-2 0.1-0.2 < 0.05 0.5-2 0.05-0.2 <0.1

Domestic background12 0.001-0.02 0.01-0.2

Operational Noise

2.11.8 Noise levels for a 132 kV OHL of the type proposed here have been predicted by the Applicant’s Design Consultant, Energyline, using a computer model, the "EMF Workstation Enviro Version 3.5" program developed by Enertech Consultants for the Electric Power Research Institute (EPRI). It should be noted that for a 132 kV OHL, the predictive capability of the model is limited, but the predicted noise level adjacent to the OHL is considered a realistic worst case.

2.11.9 The model has predicted noise levels under normal (dry) and wet weather conditions at 1 m above ground level. Worst case noise levels for a 132 kV OHL of this type is predicted under wet weather conditions. Technical Appendix 2.3 shows the calculated audible noise profiles dB(A). The L-5 curve is therefore considered a realistic worse case. Guidance17 states that the day or night time external noise

10International Commission on Non-Ionizing Radiation Protection (ICNIRP): (1998) ICNIRP Guidelines for limiting Exposure to

Time-Varying Electric, Magnetic and Electromagnetic Fields (up to 300 GHZ). Health Physics 74 (4):494‐522; 1998 11 EMF for the a 132 kV OHL of the type proposed here have been determined by SHE Transmission’s Design Consultant,

Energyline, using a computer model, the “EMF Workstation Enviro Version 3.5” program developed by Enertech Consultants for the Electric Power Research Institute (EPRI). EnergyLine (May 2012) Predictions have assumed a circuit rating of 680 MVA and a phasing of A, B, C:B, C, A

12 EMF Helpline. National Grid http://www.emfs.info/Contact.htm 13 1 microtesla = 10milligauss (mG). 14 NB: Whilst ICNRIP published updated guidance in 2010, increasing the guidelines for Magnetic field to 200 uT these have

not, to date, been adopted by UK HPA. 15 Energy Line report indicates 266.6 mG therefore 26.6 µT. 16 http://www.emfs.info/Sources+of+EMFs/Overhead+power+lines/ 17 The World Health Organisation (WH) (2009): Night Noise Guideline for Europe. ISBN 978 92 890 4173 7 recommends an

external night time noise level of 40(A) dB Leq8hour to ensure protection of vulnerable groups (children, chronically ill and elderly) but recognises that this is an onerous and precautionary level, and proposes an interim target of 55 dB(A) Leq,8 hour, as equally appropriate.


Gills Bay 132 kV


level experienced at a nearby dwelling should not exceed55 dB(A) Leq,8hour (see chapter 13: Noise for further details)18.

18 Annotations to Figure 2.8: Fair : (dry) conditions;L-5: values of noise calculated are exceeded 5% of the time; L-50: values of

noise calculated are exceeded for 50% of the time


LT000022 3-1 Chapter 3:

Environmental Impact Assessment Methodology

3 ENVIRONMENTAL IMPACT ASSESSMENT METHODOLOGY

3.1 Summary of EIA Process

3.1.1 The methodology adopted in this EIA has drawn on best practice guidance (Institute of Environmental Management and Assessment (IEMA) 2004: Scottish Executive (1998); IEMA (2011))1 to generate a robust assessment. In line with the EIA Regulations and guidance provided in EIA good practice guides, the EIA process has involved the following:

consultation and scoping with statutory consultees, non-statutory consultees and the local community to identify the key issues on which the EIA should focus;

establishing baseline environmental conditions through desktop research and site surveys;

identifying the likely effects of the Proposed Development;

determining how impacts will be avoided or reduced through design evolution or additional mitigation measures;

assessing the significance of residual environmental effects on the identified receptors against recognised or defined criteria; and

reporting the process, results and conclusions of the EIA in an ES.

3.1.2 The EIA described in this ES has identified and assessed environmental impacts on the relevant basis as identified within the individual technical assessments.

3.2 Stakeholder Consultation and Scoping

3.2.1 Best practice in EIA1 encourages consultation and engagement with stakeholders early in the process, with advice and input from key consultees being sought at the early design stages of a project, to inform decisions about the Proposed Development.

3.2.2 Stakeholder consultation and scoping differ in their objectives:

early stakeholder consultation seeks input from a wide range of both statutory and non-statutory consultees regarding the preferred design proposals during design development of the Proposed Development; and

scoping seeks input on the content of and approach to the EIA.

Stakeholder Consultation

3.2.3 Stakeholder consultation has been ongoing since initial project inception (Autumn 2010). Early consultation focused on corridor and route selection. The Applicant consulted on the Proposed Development in July 20132 seeking input from a range of statutory and non-statutory organisations on the Proposed Development, in particular explaining the rationale for the selection of the preferred route. Public

1 IEMA (2004) Guidelines for Environmental Impact Assessment, The Institute of Environmental Management and

Assessment; Scottish Executive (1998), Planning Advice Note (PAN) 1/2013, Environmental Impact Assessment; IEMA

(2011) EIA Quality Mark Commitments, April 2011: URL: http://www.iema.net/qmark

2 SHE Transmission (June 2013): Caithness Reinforcements: Gills Bay 132 kV: Consultation Document


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Chapter 3: Environmental Impact Assessment Methodology 3-2 LT000022

exhibitions were held in August 2013 at Caithness Horizons in Thurso and at Mey Village Hall, Mey.

3.2.4 Following consideration of the responses received, a further review of key design parameters was completed in order to address feedback received from the consultation.

3.2.5 Responses to the Consultation Document and public exhibitions were recorded in a separate Report on Consultation Document (March 2014).

3.2.6 Chapter 4: Design Development and Alternatives summarises the how the design for the Proposed Development was modified in response to the representations received.

Scoping

3.2.7 A request for a Scoping Opinion was made to the Scottish Government under Regulation 7 of the EIA Regulations in December 2013. A Scoping Report was submitted to support the request, which sought input from both the Scottish Government Energy Consents and Deployment Unit (ECDU); and statutory and non-statutory consultees regarding the information to be provided within this ES.

3.2.8 The following statutory and non-statutory bodies were consulted:

Table 3.1: Consultee List

Statutory Non-Statutory

Energy Consents Deployment Unit (ECDU) Royal Society for the Protection of Birds (RSPB)

The Highland Council (THC) Scottish Water

Scottish Environment Protection Agency (SEPA) Association of District Salmon Fishery Boards

Scottish Natural Heritage (SNH) Civil Aviation Authority (CAA)

Transport Scotland Forestry Commission

Historic Scotland BT Network Radio Protection

The Health and Safety Executive

Mountaineering Council of Scotland

The Ramblers Association Scotland

Scottish Rights of Way and Access Society (Scotways)

Scottish Wildlife Trust

3.2.9 Whilst no formal scoping opinion was received from ECDU in response to this request, scoping responses were received from:

THC;

SEPA;

SNH;

Transport Scotland;


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Marine Scotland; and

Historic Scotland.

3.2.10 The Scoping Report and Scoping Responses received are reproduced in Technical Appendices 3.1 and 3.2 respectively.

3.2.11 A further scoping consultation meeting was held with ECDU to confirm the scope of the ES on 27th April 2015. An updated scoping letter to ECDU issued following that meeting is included within Technical Appendix 3.3. No formal response to this letter had been received as at 21 July 2015.

3.3 Potentially Significant Issues

3.3.1 In response to the consultation received through both the scoping process and the ongoing stakeholder consultation exercise, issues relating to the following key environmental areas associated with the Proposed Development have been identified as the most relevant to the Proposed Development and are therefore addressed in the EIA and discussed in the ES:

landscape and visual amenity (Chapter 6);

ecology and nature conservation (Chapter 7);

ornithology (Chapter 8);

cultural heritage and archaeology (Chapter 9);

geology, hydrogeology and hydrology (Chapter 10);

soils, land use and agriculture (Chapter 11);

traffic and transport (Chapter 12); and

noise (Chapter 13).

3.4 Non-Significant Issues

3.4.1 A number of issues were considered to be not significant, and were scoped out from further consideration within the EIA process. Table 3.2 lists the issues scoped out and sets out the justification for doing so.

Table 3.2: Non-Significant Issues

Issue Rationale

Air Quality The Proposed Development has limited potential to give rise to some localised and temporary construction related air quality impact associated with dust (foundation construction and passage of vehicles along access tracks) and construction plant exhaust emissions. The occurrence and significance of dust generated by construction activities is extremely difficult to estimate and depends on meteorological and ground conditions at the time and location of earthworks however the nature of the construction activities is that it will be relatively low impact.

The potential for nuisance effects on residential or recreational amenity will be limited and will be strictly controlled in accordance with a detailed CEMD.

There is no potential for significant operational air quality impacts.

Socio-economics The Proposed Development may give rise to local employment opportunities during the construction phase, which in turn may give rise to individual cases of displacement impacts on local employers, i.e. the number of jobs


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Table 3.2: Non-Significant Issues

Issue Rationale

accounted for by the loss of jobs elsewhere in the locality. These impacts, should they occur, would be highly localised and on an individual basis. As such they are not considered to be significant and will not be considered further within the ES.

The Proposed Development is not predicted to have any direct impacts on local social conditions.

Electromagnetic Fields (EMF) and Radio Frequency Interference (RFI)

Chapter 2 contains information relating to the predicted electric and magnetic field strengths for a 132 kV OHL of this type and compares these values with typical values, ICNRIP3 exposure guidelines; and field strengths typical in most domestic situations.

From the data set out within Table 2.5 it is evident that the predicted electric and magnetic fields associated with the Proposed Development lie well within ICNRIP exposure guidelines.

It is also possible for radio receivers in the vicinity to be affected or interfered with by EMF. However, it is anticipated that the Proposed Development will emit low-level radio frequency interference (RFI) and that few, if any, difficulties with radio interference will arise from such RFI.

Potential for impact associated with EMF and/or RFI has not been considered further within this ES

Forestry Limited forestry clearance within the LOD of the Proposed Development will be required prior to construction commencing (a small area around Fryster and immediately around the Gills Bay substation). Figure 2.8 highlights the areas within the OHL LOD where trees are likely to be felled and mulched as part of construction enabling works.

The route alignment was developed having regard to minimising the requirement for felling.

Compensatory planting arrangements will be considered in discussion with Forestry Commission Scotland, if necessary

Forestry operations (e.g. felling) may influence timing of certain construction works. A detailed construction programme will be determined in consultation with landowners and occupiers to ensure appropriate levels of access and activity can be achieved.

No assessment of the impact associated with forestry loss has been undertaken, beyond that in Chapter 7; Ecology and Chapter 11; Soils, Land use and Agriculture.

3.5 EIA Methodology

3.5.1 The detailed methodology as applied to each environmental subject area is set out within the methodology section of the relevant Technical Chapter. Each chapter follows a consistent basic structure comprising:

Baseline Characterisation;

Impact Identification;

Assessment of Impact Significance;

3 International Commission on non-ionising radiation protection


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Mitigation; and

Assessment of Residual Effects.

3.5.2 Each chapter is also subdivided to give consideration in turn, to potential impacts both of the OHL and the underground cable elements of the Proposed Development.

3.6 Cumulative Assessment

3.6.1 Guidance states4 that cumulative effects need only be considered in the case of committed developments in the vicinity of a project under consideration. The following committed development proposals have therefore been considered, where appropriate, in assessing the effects of the Proposed Development. These are shown in Figure 3.1.

Consented

Stroupster wind farm;

Lochend wind farm;

Thurso South substation;

Dounreay – Mybster OHL connection; and

Meygen Tidal power conversion centre.

Submitted5

3.6.2 There are three applications that have been identified, which have been submitted but not yet determined or have been refused:

Spittal Hill wind farm (refused, appeal in progress);

Upper Smerral wind farm; and

Cnoc Morail wind farm (west of Watten).

3.6.3 Scottish Natural Heritage (SNH) also recommends as part of Landscape and Visual Impact Assessment (LVIA), that consideration is also given to other proposals, particularly wind farm proposals, in earlier stages of the planning process. The following earlier stage development proposals have also been identified for appropriate consideration in assessing the effects of the Proposed Development.

Pre-planning

Brabster wind farm;

Buckies farm;

Coghill wind farm (Tofts of Tain);

Cogle Moss wind farm;

Earl’s Cairn wind farm;

Gills Bay substation;

4 Scottish Planning Policy (SPP): June2014

5 Lyth Windfarm was removed from the preliminary list of cumulative developments as the most recent application was refused

by the Highland Council in November 2013.


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Seater Farm Bower wind farm;

Stemster wind farm;

Thusater Farm wind farm;

Tresdale wind farm; and

West and Northwest of Northfield wind farm.

3.6.4 In addition, due to their proximity to the proposed LOD, two potential single turbine developments were also included for consideration as part of the cumulative assessment:

Murza wind turbine; and

Brabsterdorran Turbine.

3.6.5 Not all of the developments listed above have been included within each technical chapter of the ES. Those developments that are located within 10 km of the Proposed Development have been considered by most of the technical chapters, with the exception for Chapter 6: Landscape and Visual Amenity which has considered cumulative developments within a larger area of 30 km. In addition, the assessment in Chapter 8: Ornithology, considered the impact of cumulative sites which could also impact the same designated sites that the Proposed Development could have an impact on (as indicated in Technical Appendix 8.1).

3.7 EIA Good Practice

IEMA Quality Mark

3.7.1 As with EIA, good practice in the preparation of the ES is defined in a number of sources, with more specific issues covered by ES review checklists. Many of these checklists are very detailed and go to some length. In terms of widely applicable and practical guidance, the IEMA Quality Mark scheme provides best practice review criteria against which all ESs are evaluated. Appendix 3.4 reproduces the IEMA Quality Mark ES Review Criteria, along with a description of how these indicators have been met by this ES.

Assumptions

3.7.2 Best practice guidance as set out within the IEMA Quality Mark scheme requires identification of key limitations affecting the EIA process and the resultant ES. The principal assumptions that have been made, and the main limitations that have been identified, in undertaking this EIA are set out below.

baseline conditions have been established from a variety of sources, including historical data, but due to the dynamic nature of certain aspects of the environment, conditions at the site and surrounding land uses may change;

the assessments contained within each of the technical chapters are based on the current or known draft legislative and policy framework;

the assessments contained within each of the technical chapters are based upon the LOD and OHL/underground cable alignment contained within as set out within Chapter 2: Description of the Development;

the assessments contained within each of the technical chapters are based on the assumption that mitigation measures set out in application drawings are implemented through regulatory regimes or via the management controls as


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set out in Chapter 2: Description of Development;

construction works will take place substantially in accordance with the phasing and programme of works described in Chapter 2: Description of Development; and

cumulative developments identified above will be implemented substantially in accordance with information that is publicly available or that has been provided to the Applicant, and subject to the same regulatory regimes and good practice management controls.

3.7.3 Where appropriate, assumptions specifically relevant to each topic have been set out in each chapter. Limitations in methods are identified and discussed particularly where this is likely to affect the outcomes of the assessment. As with any environmental assessment, there will be elements of uncertainty. Where relevant these are identified and reported, together with a statement on any implications on the assessment and conclusions.


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LT000022 4-1 Chapter 4:

Route Selection Alternatives

4 ROUTE SELECTION AND ALTERNATIVES

4.1 Introduction

4.1.1 This chapter outlines of the alternatives which were considered, and the main reasons for the choices made, leading to the final configuration of the Proposed Development. These alternatives took into account potential for environmental effects, in accordance with the requirements of Schedule 4 of the EIA Regulations1.

4.1.2 An iterative process of design development and route selection (the routing process) has been completed since project inception in 2010, in response to anticipated increases in renewable generation within the wider area which will require connection to the transmission grid. The process is summarised in Technical Appendix 4.1. This chapter summarises key stages in this routing process and the alternatives which have been considered at each stage in order to reach the final design, namely the Proposed Development, as described in Chapter 2 of this ES.

4.1.3 The routing process and the final configuration of the Proposed Development has been informed throughout by the consideration of a balance of factors including engineering feasibility, environmental sensitivities, network resilience and cost factors as well landowner and wayleave considerations.

4.1.4 The routing process has been supported throughout by an ongoing process of consultation with statutory consultees, landowners and the general public, and by environmental analysis.

4.2 Development Considerations

4.2.1 The Applicant, as a licence holder under the Electricity Act 1989, 'when formulating proposals to generate, transmit, distribute or supply electricity' is required, under Schedule 9 to:

'have regard to the desirability of preserving natural beauty, of conserving flora, fauna and geological or physiographical features of special interest and of protecting sites, buildings and objects of architectural, historic or archaeological interest'; and

'do what he[sic] reasonably can to mitigate any effect which the proposals would have on the natural beauty of the countryside or on any such flora, fauna, features, sites, buildings or objects.'

4.2.2 The Applicant also has obligations under section 9 of the 1989 Act to 'develop and maintain an efficient, co-ordinated and economical system of electricity distribution'. Furthermore, the requirements of the Construction (Design and Management) Regulations 20152 (CDM regulations) require that the design aims to minimise hazards and reduces risks during construction3.

4.2.3 In addition to these obligations the approach to routing has been informed by the Applicant’s own guidance which sets out the key routing principles for high voltage

1 Electricity Works (Environmental Impact Assessment ( (Scotland) Regulations 2000; 2 The new 2015 CDM regulations took effect on 6th April 2015 and replaced the 2007 CDM Regulations; 3 The CDM regulations make ‘designing out’ risk to health and safety a key project requirement;


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Chapter 4: Route Selection Alternatives 4-2 LT000022

steel lattice tower transmission OHLs4. Specifically, this guidance applies the Holford Rules (Technical Appendix 4.2), first developed in 1959 by Sir William Holford, which set out guidance relating to the routeing of overhead electricity transmission lines and the consideration which should be given to environmental features and which continue to inform transmission line routeing in the UK today.

4.2.4 Taking account of these obligations, the Applicant has considered engineering, economic and environmental factors in evaluating the alternatives for the Proposed Development, with the objective of identifying a proposed route and associated LOD which are 'technically feasible and economically viable' and 'which causes the least disturbance to the environment and to the people who live, work, visit and recreate within it'. A timeline of environmental inputs into the design and routing process has been produced to allow the extensive process of routing and consideration of alternatives to be understood. The timeline is included in Technical Appendix 4.1.

4.3 Do-Nothing Alternative

4.3.1 The "do nothing" scenario is a hypothetical alternative sometimes considered in EIA as a basis for comparing the development alternatives under consideration. Within the context of the Proposed Development the 'do nothing' scenario would involve the electricity network in Caithness remaining in its current form, which does not currently include any transmission connection at 132 kV or greater to the east of Thurso.

4.3.2 The Applicant has contracts from National Grid which mean that they are obligated to provide a connection for MeyGen Ltd, (tidal turbine development in the Inner Pentland Sound) and to Scottish Hydro Electric Power Distribution (SHEPD) for a 900MW distribution connection. In this context the 'do nothing' alternative is not a viable alternative.

4.4 Alternative Corridors

Single Circuit, 132 kV radial OHL between Dounreay and Gills Bay (2010 – 2011)

4.4.1 Early strategic level considerations were completed as part of strategic network reinforcement planning (2010-2011) (refer to section 1.2 of this ES) incorporating a study area extending from Dounreay in the west to Gills Bay in the east and as far south as Spittal.

4.4.2 These early considerations sought to identify a preferred corridor for a single circuit 132 kV radial OHL on woodpole trident supports.

4.4.3 A corridor from Dounreay to Gills Bay via Spittal was preferred based on engineering considerations. A more northerly corridor between Dounreay and Gills Bay via Thurso was preferred in environmental terms as it offered the opportunity to minimise routing across peatland and associated sensitive habitats, when compared to the southern route.

4.4.4 These two corridors are shown on Figure 4.1.

4 Scottish Hydro Electric Transmission Limited (October 2004) Electricity Transmission Development Proposals in Scotland: A Guidance Document Outlining The SHETL Approach To The Routeing Of High Voltage Steel Lattice Tower Transmission Lines, Leading To An Application For Consent In Scotland (TG-PS-532 rev1.01)


LT000022 4-3 Chapter 4:


Dual Circuit, 132 kV radial OHL between Gills Bay and Dounreay (2012)

4.4.5 By 2012, the Applicant had identified the requirement for the Proposed Development to provide a dual circuit connection rather than a single circuit connection as previously identified. As a result both the southern (Dounreay-Spittal-Gills Bay) and the northern (Dounreay-Thurso-Gills Bay) corridors were progressed.

4.4.6 An alternative alignment of the northern corridor between Thurso and Gills Bay was added to address engineering concerns relating to the integrity of the sandy soils along the northern corridor and its potential ability to support OHL foundations. This alternative alignment to the northern corridor was also proposed on environmental grounds, to increase the separation distance between the Proposed Development and known sensitive environmental receptors including the Dunnet Links SSSI and residential properties at Castletown.

4.4.7 The alternative alignment of this northerly corridor (Corridor F2) is also shown on Figure 4.1.

Dual Circuit, 132 kV radial OHL between Thurso South and Gills Bay (2012)

4.4.8 By late 2012, the Applicant’s ongoing technical options appraisal, coupled with the design evolution for the new substation at Thurso South, confirmed the suitability of design and capacity of this new substation to allow the Proposed Development to connect to the grid through Thurso South substation rather than routing through to Dounreay.

4.4.9 This development allowed the alternative for a 132 kV OHL connection from Dounreay through to Thurso to be discounted thereby bringing an overall reduction in the extent of OHL required Consequently the alternative alignment of the northerly corridor between Thurso and Gills Bay was confirmed as the preferred corridor.

4.5 Alternative Routes and Conductor Support Types within the Preferred Corridor

4.5.1 Following identification of the preferred corridor, a routing study was completed in early 2013 in order to evaluate alternative routes associated with the preferred corridor.

4.5.2 The study area for the routing study was defined as the area within and surrounding the preferred corridor and covered the broad area between Thurso to the west, Gills Bay to the east, the coast to the north and Durran and Reaster to the south as shown on Figure 4.2. Key environmental constraints identified within the study area are also shown on Figure 4.2.

Alternative Conductor Support Types

4.5.3 Whilst early considerations of alternatives focused on the requirement to deliver a 132 kV OHL supported on trident woodpoles (see section 4.4 of this ES), further development of the Applicant’s technical options appraisal, subsequently identified the requirement to give consideration of the relative merits of alternative conductor support types.

4.5.4 Three alternative conductor support types were considered:


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a twin trident configuration, comprising two 132 kV OHL circuits supported on H pole supports, running in parallel along a single route alignment;

a dual trident configuration, in which two 132 kV OHL circuits supported on H Pole supports would be installed following different alignments between the two identified connection points; and

a single lattice steel tower of L7 (see section 2.4 of this ES) design and cable of carrying both circuits.

4.5.5 The dual trident alternative was not considered to be technically feasible and would in addition incur significant extra costs associated with securing access and wayleaves and was therefore also not considered economically viable. In addition, as the project had developed to allow connection into Thurso South Substation, there was no requirement for different alignments to be followed by the dual trident option to meet customers’ connection requirements. The dual trident alternative was therefore not considered any further.

4.5.6 Possible alternative routes for both the twin trident and the steel lattice tower alternatives were then considered in environmental terms.

Alternative Routes

4.5.7 Five alternative routes were considered within the 2013 routing study. These are shown in Figure 4.3.

4.5.8 Consideration of technical and engineering parameters led to the identification of four alternative routes considered capable of accommodating a connection utilising either twin trident woodpoles or steel lattice towers. The fifth route was considered for a twin trident woodpole OHL only.

4.5.9 Subsequent environmental consideration of these alternatives was informed by the Holford Rules (see Technical Appendix 4.2). These rules set out guidance relating to routing of OHLs, and the consideration which should be given to environmental features. Alternative routes were appraised in environmental terms taking into account (amongst other factors) the potential to avoid major areas of highest amenity value, as well as the opportunity to avoid smaller areas of amenity value or scientific interests. Landscape setting issues were also considered along with the frequency of angle changes and other issues relating to potential visual complexity along the alternative routes.

4.5.10 The preferred connection option identified through this process was for steel lattice towers following the alignment shown in Figure 4.3 (Connection Option 1A).

4.5.11 Steel lattice towers were preferred over the twin trident woodpole option due to the reduced impact on land use to take forward the former option. Steel towers have a 250 m span between towers, compared to a 110 m span between trident woodpoles. Therefore the trident woodpole option would require more than double the number of supports, with a proportionally greater impact on land use (resulting in potential partial land sterilisation), disturbance of soils and greater access requirements.

Post Consultation Variations

4.5.12 Consultation on the preferred connection option (Figure 4.3) was completed during the summer of 2013.


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4.5.13 Following consultation, six possible variations to the preferred connection option were considered in order to respond to environmental queries raised by the consultees, including:

potential for effect on residential amenity and on the Tulloch of Shalmstry Scheduled Monument (SAM) at the western end of the route;

potential for effect on landscape and visual amenity particularly across the Hill of Olrig, around Durran and between Wester Olrig and Reaster;

potential for interference with TV and radio transmitter masts located on the summit of the Hill of Olrig;

potential for effects on visual amenity, particularly in views from the A9;

potential for interaction with sensitive bird species, particularly between Lochend and Syster and around Durran; and

potential for effects on visual amenity for individual residential properties to have secondary effects on value of land and property at Bowermadden and Moss of Tain.

4.5.14 These variations are shown on Figure 4.4. The resultant post consultation alignment was reported in the Report on Consultation (see Technical Appendix 3.5 of this ES) and is shown on Figure 4.5 (Variation 4 – with undergrounding of the section marked 4A).

4.5.15 One further variation (Variation 5 on Figure 4.5) was also incorporated into the proposed connection option taken forward to first draft technical impact assessment, in order to further address potential effects on visual amenity for individual residential properties at Moss of Tain.

Initial Technical Impact Assessment – Alternative Mitigation Options

4.5.16 The outcome of the initial technical impact assessment completed based on the proposed connection option shown in Figure 4.5 resulted in a further set of variations being considered in order to integrate appropriate mitigation measures into the design of the Proposed Development. These variations are shown on Figure 4.6.

4.5.17 These variations were proposed in order to respond to:

results from initial ornithological collision risk assessment, indicating potential for significant residual effects on the integrity of the local SPA population of white fronted goose Anser albifrons flavirostris and whooper swan Cygnus cygnus;

potential to disturb known feeding and loafing areas for SPA bird species around Loch of Durran;

results from initial landscape and visual impact assessment, indication potential for significant residual effects on visual amenity at a number of viewpoints; and

concerns raised by SEPA in relation to potential for significant effect on wetland hydrology and groundwater dependent terrestrial ecosystems, in the event of underground cabling, particularly in the area around the Moss of Greenland.

4.5.18 The resultant parameters of the Proposed Development (the option taken forward was the Balanced Design Mitigation Option (Sep 2014) with Option 1 undergrounded) are as described in Chapter 2: Description of the Development.


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LT000022 5-1 Chapter 5:

Planning and Policy Context

5 PLANNING AND POLICY CONTEXT

5.1 Introduction

5.1.1 This chapter outlines the rationale for the Proposed Development and the policies at the national Scottish Government and local planning authority levels that are considered material to its consideration by the Scottish Ministers under the Electricity Act 1989. The application for consent is accompanied by a Planning Statement which provides an assessment of the Proposed Development within the context of the policies discussed within this chapter.

5.2 Development Considerations

5.2.1 Much Scottish Government policy is directed toward the encouragement of renewable energy to tackle climate change and deliver economic benefit in Scotland. The need for grid reinforcement and network development is a direct result of policies which are aimed at stimulating the expansion of renewable energy generation. Hence, high level policies on energy, climate change and renewable energy in planning terms are indirectly linked to the determination of the Proposed Development.

5.2.2 Other aspects of national planning policy relating to landscape conservation, biodiversity protection and enhancement etc. is detailed at the beginning of each topic chapter within this ES.

5.3 National Policy

National Planning Framework

5.3.1 The National Planning Framework 3 (NPF3) published in 2014 is Scotland’s Third National Planning Framework. The NPF3 gives firm support for growing renewables. Core parts of the Framework relate to the realisation of the potential of Scotland’s renewable energy resources, recognising the importance of developing nationally designated grid reinforcements.

5.3.2 The NPF3 also identifies the matters that must be addressed when consent is sought: the likely need for Environmental Impact Assessment (EIA) and Habitat Regulations Assessment; the routes of any new overhead lines and underground cables; the siting and design of any new structures; carbon impact; landscape and visual impacts; effects on bird species; other aspects of biodiversity; soils; hydrology; hydrogeology; the coast and marine environment; effects on the historic environment, and; any measures necessary to minimise, mitigate or compensate for adverse effects on the environment or communities, including strategic level or whole scheme measures.

5.3.3 The Framework acknowledges that enhancements to the high voltage electricity grid transmission network across Scotland will facilitate increased renewable electricity generation. Consequently it considers that enhancements comprising the following will in future constitute national development:

new and/or upgraded onshore electricity transmission cabling of or in excess of 132 kilovolts and supporting pylons;


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Chapter 5: Planning and Policy Context 5-2 LT000022

new and/or upgraded onshore substations directly linked to electricity transmission cabling of or in excess of 132 kilovolts;

new and/or upgraded onshore converter stations directly linked to onshore and/or offshore electricity transmission cable(s) of or in excess of 132 kilovolts; and

new and/or upgraded offshore electricity transmission cabling of or exceeding 132 kilovolts.

5.3.4 Whilst the related Map of Proposed National Developments illustrates the spatial location of such enhancements (including Caithness/Orkney), the supporting text emphasises that this is an indicative picture only and that proposals may change.

Scottish Planning Policy

5.3.5 Scottish Planning Policy (SPP)1 provides a statement of the Scottish Government’s policy on nationally important land use matters and reaffirms that electricity generated from renewable sources is a vital part of the response to climate change.

5.3.6 The SPP identifies that planning can support the transition to a low carbon economy and help tackle climate change. Scotland’s renewable energy resources are identified as an exceptional opportunity to drive down greenhouse gas emissions and promote sustainable economic growth. Strategic development plans are required to support national priorities for the construction or improvement of strategic energy infrastructure, including energy transmission networks.

Climate Change Scotland Act

5.3.7 The Scottish Government has set a goal of reducing greenhouse gas emissions, the main contributor to global warming, by 42% by 2020 ( based on 1990 emissions levels) and 80% by 2050 (based on 1990 emissions levels). These statutory targets are set out in the Climate Change (Scotland) Act 20092.

5.3.8 The Scottish Government has been supporting achievement of these targets within devolved energy policy areas through a variety of initiatives and measures including the promotion of renewable energy and energy efficiency, as well through spatial planning and its economic development strategy.

5.3.9 Section 35 of the Act requires Scottish Ministers to publish a ‘report on proposal and policies’ (an RPP) setting out how Government actions across a range of activities, policies and programmes are helping make progress towards the targets. The first RPP3 was published in March 2011 and looked at four transformational areas identified in the Scottish Government’s Climate Change Delivery Plan4 including decarbonisation of the electricity generation sector (see the Electricity Generation Statement, paragraphs 5.3.7 – 5.3.8).

1 Scottish Government (June 2014): Scottish Planning Policy.

2 Climate Change (Scotland) Act 2009

3 The Scottish Government (March 2011) Low Carbon Scotland: Meeting the Emissions Reduction Targets 2011-2022: The

Report on Proposals and Policies

4 The Scottish Government (2009): Scottish Government’s Climate Change Delivery Plan


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2020 Routemap for Renewable Energy in Scotland

5.3.10 The Scottish Government’s 2020 Routemap for Renewable Energy in Scotland5, established a target for the equivalent of 100 % of Scotland’s electricity demand to be supplied from renewable sources by 2020 and that at least 30 % of overall energy demand to be met from renewable resources by this date.

5.3.11 After exceeding its interim target to meet 31 % of electricity demand from renewables by 2011, the Scottish Government confirmed that it had set a new more ambitious interim target for 50 % by 2015 in its first annual update of the Routemap6. The target to meet at least 30 % of overall energy demand from renewable resources by 2020 is also contained in the NPF37.

Electricity Generation Statement

5.3.12 The Scottish Government’s Electricity Generation Statement 2013 examines the way in which Scotland generates electricity and considers the changes which will be necessary to meet the targets which the Scottish Government has established. It contains a commitment to work towards the decarbonisation of the electricity generation sector by 2030: with a target for carbon intensity of 50g/CO2/kWh for electricity generation in Scotland8.

5.3.13 The Statement also notes the need for on-going transmission upgrade and reinforcement across Scotland, including work to address some of the grid issues faced by developers in Scotland’s islands.

Energy Efficiency Action Plan

5.3.14 The Scottish Government published its Energy Efficiency Action Plan in autumn 20109. It established a target to reduce final energy demand in Scotland by 12 % by 2020 from a 2005-7 baseline, covering all fuels and sectors. Although the baseline is likely to be revised annually by Department of Energy and Climate Change (DECC), (and the baseline datasets could go up or down), the Scottish Government remains committed to the principle of adhering to the 12 % target.

Government Economic Strategy

5.3.15 Energy is recognised as a key sector in the Scotland’s Economic Strategy 2015 (GES)10, with sustainable energy development contributing to reduce emissions and promote sustainable economic growth. The GES builds on the Renewables Action Plan (2009)11, the earlier Low Carbon Economic Strategy for Scotland (2010)12 and the National Renewables Infrastructure Plan (2010)13.

5 The Scottish Government (June 2011): 2020 Routemap for Renewable Energy in Scotland

6 The Scottish Government (October 2011): Update to 2020 Routemap for Renewable Energy.

7 The Scottish Government (June 2014): Scotland’s Third National Planning Framework

8 The Scottish Government (June 2013): Electricity Generation Policy Statement – 2013.

9 The Scottish Government (October 2010): Conserve and Save: Energy Efficiency Action Plan.

10 The Scottish Government (March 2015): Scotland’s Economic Strategy.

11 The Scottish Government (July 2009): Renewables Action Plan.

12 The Scottish Government (November 2010): A Low Carbon Economic Strategy for Scotland.

13 Scottish Enterprise (July 2010): National Renewables Infrastructure Plan.


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5.4 Regional Policy

5.4.1 The Proposed Development is located within Caithness in the Highlands of Scotland. The local planning authority for Caithness is The Highland Council (THC).

5.4.2 The Planning etc. (Scotland) Act 2006 introduced a new statutory basis for development planning in Scotland. It inserted a new Part 2 into the Town and Country Planning (Scotland) Act 1997 requiring the replacement of regional/sub-regional structure plans and local plans outwith the nation’s four largest city region areas, with a new system of local development plans supported by Supplementary Guidance (SG)14.

5.4.3 THC adopted the Highland-wide Local Development Plan (HwLDP) on 5th April 201215. It supersedes the 2001 Highland Structure Plan (outwith the Cairngorms National Park) and the ‘general policies’ of the existing adopted Local Plans i.e. the 2002 Caithness Local Plan (CLP). The Council’s Development Plan Scheme16 explains that the HwLDP provides a consistent policy framework for assessing planning applications across the region, except the National Park.

5.4.4 Some elements of the CLP, however, have been retained and remain in force. These are identified in Appendix 7 of the HwLDP (the Retention Schedule). The retention in part of adopted Local Plans allows the Council to retain in force a set of land allocations and some local policies/proposals to help facilitate and manage development across Highland.

5.4.5 The Council has begun work on a new local development plan for the Caithness and Sutherland area (‘CaSplan’), which will set out a vision and development strategy for the area over the next 20 years. Once formally adopted it will replace the retained elements of the existing CLP. The publishing and consultation on the Proposed Plan is expected in winter 2015.

5.4.6 Whilst yet to be formally adopted, the CaSplan continues the commitment of the CLP for the region to be a centre of excellence for energy and engineering. The Proposed Development is located within the designated ‘Energy Business Expansion’ strategy zone and the preferred approach of the consultation document is to continue the plan for a wide range of renewable energy developments.

5.4.7 As with aspects of the national planning policy, the early parts of each ES chapter set out relevant regional and local planning policy for the specific topic.

Highland-wide Local Development Plan 2012

5.4.8 The HwLDP promotes a balanced strategy to support the sustainable growth of all communities across the Highlands and a competitive economy whilst safeguarding the environment. Renewable energy is to be encouraged in suitable locations together with the improvement of strategic infrastructure necessary to allow the economy to grow over the long term.

14 Scottish Government (2013): Circular 6/2013 Development Planning.

15 The Highland Council (April 2012): Highland-wide Local Development Plan.

16 Highland Council (2014): The Highland Development Plan Scheme


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5.4.9 The HwLDP seeks to regenerate Caithness as a centre of excellence for energy and engineering, especially in renewables, whilst protecting and enhancing the area’s outstanding heritage. It also recognises the need to develop electricity transmission and distribution infrastructure in order to realise the area’s potential contribution to renewable electricity generation and contribute to national requirements. The Caithness (and Sutherland) Vision and Spatial Strategy Diagram (page 17 of the HwLDP) specifically acknowledges strategic electricity grid reinforcements.

5.4.10 The policies that are considered material to the Proposed Development are set out in Table 5.1 below:

Table 5.1: Material Policies in the Highland-wide Local Development Plan

Policy Reference Policy Summary

Policy 28 – Sustainable Design

The Council will support developments which promote and enhance the social, economic and environmental well-being of the people of Highland. It will require assessments of socio-economic and environment impacts where these are likely to be significant.

Policy 29- Design Quality & Place-making

Development should demonstrate sensitivity and respect towards key design/contextual factors including local distinctiveness of the landscape.

Policy 30- Physical Constraints

Developers must consider if their proposals are affected by the Physical Constraints Supplementary Guidance and if so, demonstrate compatibility and/or satisfactory mitigation measures.

Policy 36 – Wider Countryside

Development may be supported if judged not significantly detrimental when assessed against factors such as: siting and design; landscape character and capacity; drainage.

Policy 47 – Safeguarding Inbye/Apportioned Croftland

Development is expected to minimise impact on such land, where possible avoiding: siting on the better part of the croft in terms of its agricultural value, and; impeding use of the remainder.

Policy 51 – Trees and Development

Development promoting significant protection to hedges, trees and woodlands will be supported. Management plans may be required where appropriate.

Policy 55 – Peat and Soils

Development proposals should demonstrate how they have avoided unnecessary disturbance, degradation or erosion of peat and soils. Where development on peat is clearly demonstrated to be unavoidable, the Council may ask for a peatland management plan to minimise and mitigate impacts.

Policy 56 - Travel Where appropriate, the Council will require sufficient information to assess the likely on and off-site transport implications of development.

Policy 57 – Natural, Built and Cultural Heritage

Development proposals will be assessed taking into account the level of importance and type of heritage features, the form and scale of the development and any impact on the feature and its setting in the context of the policy framework detailed in Appendix 2 of the HwLDP. For features of local/regional importance, development will be allowed provided there are no unacceptable impacts on the natural environment, amenity and heritage resource.


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Table 5.1: Material Policies in the Highland-wide Local Development Plan

Policy Reference Policy Summary

Policy 58- Protected Species

Where there is a likelihood development could affect a protected species, survey information will be required to verify presence and if necessary inform mitigation measures.

Policy 59 – Other Important Species

The presence of and likely impact of development on other important species will be taken in account.

Policy 60 - Other Important Habitats

The Council will seek to safeguard the integrity of landscape features of major fauna and flora importance due to their linear and continuous character or combination as habitat stepping stones.

Policy 61 - Landscape Development should be designed to reflect the local characteristics and qualities in the Landscape Character Assessment.

Policy 63 – Water Environment

Development that does not compromise the Water Framework objectives to protect and improve the water environment will be supported.

Policy 64 – Flood Risk Development should avoid areas susceptible to flooding and promote sustainable flood management. Proposals within or bordering medium to high risk flood areas require supporting information e.g. a Flood Risk Assessment to show compliance with SPP.

Policy 66 – Surface Water Drainage

Development must be drained by appropriately designed Sustainable Drainage Systems.

Policy 69 – Electricity Transmission Infrastructure

Proposals for electricity transmission infrastructure will be considered having regard to their level of strategic significance. Subject to this factor and taking into account mitigation, the Council will support proposals that will not have an unacceptable environmental impact.

Policy 70 – Waste Management Facilities

Development will be assessed against criteria that include: suitability of the local road network for site access; public health and safety and minimisation of transport of waste from its source.

Policy 72- Pollution Proposals likely to create significant pollution (including noise) will only be approved where a submitted assessment shows it will be avoided and if necessary mitigated. Major Developments and those involving Environmental Impact Assessment will be expected to follow a robust project environment management process such as that in the Council’s Guidance Note “Construction Environmental Process for large Scale Projects”.

Policy 77 – Public Access

Major Development proposals require the submission of an Access Plan detailed public access provision before, during and after construction.

Policy 78 – Long Distance Routes

The Council will safeguard and seek to enhance these routes and their settings.

Statutory Supplementary Guidance

5.4.11 THC has adopted the documents in Table 5.2 as part of their Development Plan.


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Table 5.2: Statutory Supplementary Guidance adopted by Highland Council

Document Title Summary

Flood Risk and Drainage Impact Supplementary Guidance, January 2013

This guidance aims to explain the Council’s policies on flooding and drainage and the responsibilities of all parties with an interest in these issues. It seeks to improve the design and implementation of developments and ensure that appropriate development takes place in appropriate locations.

Highland Historic Environment Strategy Supplementary Guidance, January 2013

The purpose of this guidance is to ensure that future developments take account of and protect the historic environment. It supports applications for development in historically and archaeologically sensitive areas.

Sustainable Design Supplementary Guidance, January 2013

This guidance supports the approach to Sustainability and Design in the HwLDP and focuses on landscape matters.

Trees, Woodlands and Development Supplementary Guidance, January 2013

The purpose of this guidance is to help developers properly consider and subsequently manage existing trees and woodlands, as well as identifying opportunities for the planting and management of trees and woodland.

Physical Constraints Supplementary Guidance, March 2013

This guidance gives developers information on constraints that could put human health and safety at risk e.g. noise, other pollution and slope stability.

Highland’s Statutorily Protected Species, Supplementary Guidance, March 2013

This guidance seeks to explain protected species legislation and how this affects development.

Managing Waste in New Developments Supplementary Guidance, March 2013

This guidance sets out the provisions to be made by developers to incorporate waste management requirements within developments at an early stage of design.

5.5 Local Policy

Caithness Local Plan 2002 (Retained Elements)

5.5.1 The Caithness Local Plan (CLP) seeks to create a growing population and expand the economy whilst improving communications and services and improving the environment. One of its strategic infrastructure objectives is to support the development of renewable energy in suitable locations within Caithness. On the environmental front, the CLP contains a strategic objective to promote the area's biodiversity and to safeguard and enhance the area’s natural and cultural heritage.

5.5.2 There are no retained primary policies within the CLP governing development in the countryside.

5.6 Other Guidance

5.6.1 At national level, planning policy is supported by Scottish Government guidance on a range of planning matters e.g. Planning Advice Notes (PAN) and Circulars. Their contents do not form policy but may constitute a material consideration depending


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on particular circumstances. The nationally produced guidance considered relevant to the Proposed Development is provided in Table 5.3 below.

Table 5.3: Scottish Government Guidance


PAN 1/2013 Environmental Impact Assessment

Contains guidance on the integration of EIA procedures into the development management process, as a step towards more efficient and effective EIA.

PAN 1/2011 Planning and Noise 2011

This Planning Advice Note provides advice on the role of the planning system in helping to prevent and limit the adverse effects of noise.

PAN 2/2011 Planning and Archaeology 2011

The Archaeology PAN reflects 17 years of accumulated changes in the policy context, the statutory planning system, the key stake holders and in archaeological practices. Like its 1994 predecessor (PAN 42) provides advice to planning authorities and developers on handling archaeological matters within the planning process. But it does so with a fresh emphasis which is proportionate to the relative value of remains and of the development under consideration.

PAN 51 Planning Environmental Protection and Regulation 2006

This PAN supports the existing policy on the role of the planning system in relation to the environmental protection regimes. It also summarises the statutory responsibilities of the environmental protection bodies.

PAN 60 Planning for Natural Heritage 2000 (amended 2008)

This PAN deals with how biodiversity and landscape concerns should be addresses in development planning and management. It sets out the role and responsibilities of SNH and other stakeholders.

PAN 61 Planning and Sustainable Urban Drainage Systems 2001

This PAN provides good practice advice for planners and the development industry complementing the Sustainable Urban Drainage Systems (SUDs) Design Manual for Scotland and Northern Ireland, which was published by CIRIA in March 2000 for the Sustainable Urban Drainage Scottish Working Party.

PAN 63 Waste Management Planning 2002

This PAN covers the waste management aspects of planning of non-waste developments including construction waste issues.

PAN 68 Design Statements 2003

This PAN explains what a design statement is, why it is a useful tool, when it is required and how it should be prepared and presented. The Annex describes the design process.

PAN 69 Planning and Buildings Standards Advice on Flooding 2004

This PAN contains good practice advice on planning and building standards in areas where there is a risk of flooding.

PAN 75 Planning and Transport 2005

This PAN aims to create greater awareness of how linkages between planning and transport can be managed. It highlights the roles of different bodies and professions in the process and points to other sources of information.

Transport Assessment Guidance (Transport for Scotland) Undated.

Most new developments and changes of use will have some form of transport implication. Given the policy significance of the links between land use and transport the likely transport impacts of development proposals need to be identified and dealt with as


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Table 5.3: Scottish Government Guidance


early as possible in the planning process. This document seeks to provide a better practice guide to help identify and deal with the likely impacts.

5.6.2 THC has also produced guidance and advice that it is not proposing to adopt as part of the Development Plan but the contents of which are capable of constituting material planning considerations. The Council-produced guidance considered relevant to the Proposed Development is provided in Table 5.4 below.

Table 5.4: Highland Council Planning Guidance


Construction Environmental Management Process for Large Scale Projects 2010

This guidance sets out a robust Project Environmental Management Process (PEMP) for large scale projects and concentrated on the construction stage of the development.

Highland Renewable Energy Strategy and Planning Guidelines 2006

This guidance was published in 2006 prior to the adoption of HwLDP which contains Policy 69 – Electricity Transmission Infrastructure. The main purpose of the document is to identify the capacity in the Highlands for a range of renewable energy targets and provide locational guidance and support economic development.

Design Statements and Design and Access Statements (undated)

This guidance details the general content and format of a design statement.

Transport Guidance for New Developments 2013

This guidance sets out advice and standards for the provision of transport infrastructure within the Highland area including the design and construction of all new roads associated with development.

Badger Policy Guidance Note 2007

This guidance outlines good practice advice in relation to development proposals in areas where there is potential to impact upon badgers.

Badger Best Practice Guidance 2006

This guidance details the licences and laws surrounding the protection of badgers and the role SNH maintain as a licence officer.

Badger Best Practice Guidance - Badger Protection Plans 2006

This guidance details the information which should be included within a Badger Protection Plan (BPP).

Badger Best Practice Guidance - Badger Surveys 2006

This guidance highlights the design and scope of different types of badger surveys.

5.7 Summary

5.7.1 This chapter has outlined economic, energy, environmental and planning policy considered to be relevant to the determination of the Proposed Development, including national, regional and local dimensions. It has also identified guidance related to these policies.


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5.7.2 A detailed assessment of the Proposed Development against the policies contained in this chapter is included in a separate Planning Statement.


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Landscape and Visual Amenity

6 LANDSCAPE AND VISUAL AMENITY

6.1 Introduction

This chapter considers the likely effects on the character of the landscape1 resource and, with reference to views from specific locations in the area, on visual amenity of the Proposed Development.

The specific objectives of this assessment were to: • identify key landscape and visual designations in the vicinity of the Proposed

Development;

• describe the nature and sensitivity of the landscape character and visual amenity baseline conditions in the vicinity of the Proposed Development;

• describe the likely effects, including direct and indirect / temporary or permanent effects, which may arise from the Proposed Development;

• assess the significance of likely effects arising from the construction and operation of the Proposed Development;

• propose measures, where appropriate, to mitigate any predicted significant adverse effects; and

• assess the significance of likely effects taking into consideration any committed mitigation proposals.

This chapter, and the impact assessment described within, has been prepared by Roz Maclennan, BA Hons in Landscape Architecture, Chartered Member of the Landscape Institute (Design Division) of horner + maclennan (h+m) Landscape Architects. It is supported by Technical Appendices 6.1 – 6.4, contained in Volume 4 of the Environmental Statement (ES), and Figures 6.1 – 6.25, contained in Volume 3 of the ES. All field surveys were completed by suitably qualified landscape architects from h+m.

6.2 Legislation and Policy Context National Legislation and Policy

National Planning Framework 3, 2014 and Scottish Planning Policy, 2014

The National Planning Framework (NPF) and Scottish Planning Policy (SPP) share a single vision for the planning system in Scotland: • ‘We live in a Scotland with a growing, low-carbon economy with progressively

narrowing disparities in well-being and opportunity. It is growth that can be achieved whilst reducing emissions and which respects the quality of environment, place and life which makes our country so special. It is growth which increases solidarity – reducing inequalities between our regions. We live in sustainable, well-designed places and homes which meet our needs. We

1 Landscape is defined in the European Landscape Convention (Council of Europe 2000) as ‘an area, as perceived by people,

whose character is the result of the action and interaction of natural and/or human factors. The term does not mean just special or designated landscapes and it does not only apply to the countryside. Landscape can mean a small patch of urban wasteland as much as a mountain range and an urban park as much as an expanse of lowland plain. It results from the way that different components of our environment - both natural (the influences of geology, soils, climate, flora and fauna) and cultural (the historical and current impact of land use, settlement, enclosure and other human interventions) - interact together and are perceived by us.’


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Chapter 6: Landscape and Visual Amenity 6-2 LT000022

enjoy excellent transport and digital connections, internally and with the rest of the world.’

NPF3 and SPP 2014 share four planning outcomes in common, to support the overall vision: • outcome 1: A successful, sustainable place – supporting sustainable economic

growth and regeneration, and the creation of well-designed, sustainable places;

• outcome 2: A low carbon place – reducing our carbon emissions and adapting to climate change;

• outcome 3: A natural, resilient place – helping to protect and enhance our natural and cultural assets, and facilitating their sustainable use; and

• outcome 4: A more connected place – supporting better transport and digital connectivity.

The relevant Subject Policies for this LVIA, set out to deliver the required outcomes on the ground, include: • Promoting Rural Development;

• Valuing the Historic Environment;

• Delivering Heat and Electricity; and

• Valuing the Natural Environment.

Regional Policy

The Highland-wide Local Development Plan (HwLDP), 2012

The HwLDP delivers the requirements of the SPP in the area of the Proposed Development.

The following HwLDP policies are relevant to this assessment: • Policy 36 - Development in the Wider Countryside, requires that development

should be sympathetic to existing patterns of development and compatible with landscape character and capacity, whilst avoiding incremental expansion affecting the mix/distribution of the characteristics of landscape character.

• Policy 51 - Trees and Development, aims to protect existing hedges, trees and woodland and may require the preparation of a management plan. It also allows for the Council to require tree/hedge planting to compensate for the removal of existing vegetation and to enhance the setting of new development.

• Policy 57 - Natural Built and Cultural Heritage, requires that all development proposals are assessed taking into account the level and importance of heritage features, the form and scale of development and any impact on the feature or its setting.

• Policy 61 - Landscape, requires that new development be designed to reflect the landscape characteristics and special qualities of the area in which they are proposed.

• Policy 69 - Electricity Transmission Infrastructure, supports proposals which have been assessed as not having an unacceptable significant impact on the environment.


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Local Policy

The HwLDP as discussed above now supersedes large parts of the ‘Caithness Local Plan 2002’. However a Parliamentary Order has been made to retain elements of these plans prior to the adoption of the forthcoming Area Local Development Plans. Elements that remain applicable to the Proposed Development are listed below: • The Caithness Local Plan (as continued in force, 2012) covers the whole of the

study area and includes policy which ‘tends to favour development, unless this would significantly affect important features'. Specifically Policy 46 includes for the safeguarding of scenic views from unsympathetic development. Views from public roads to open water are identified as particularly important for amenity and tourism.

The Caithness and Sutherland Local Development Plan, the second of the local development plans, is currently being prepared by The Highland Council and, once adopted, will supersede the existing Caithness Local Plan (as continued in force, 2012).

6.3 Issues Identified During Consultation

SNH provided a scoping response on 18th February 2014 highlighting a number of landscape and visual considerations to be taken into account during the assessment process. SNH also provided comment on the selected viewpoints on 28th November 2013.

The Highland Council responses were received on 17th July 2014.

No scoping opinion had been received from ECDU as at 21st July 2015.

The following table summarises the issues taken into account.

Table 6.1: Issues Identified During Consultation

Consultee Issue How/where this is addressed

THC THC requested that cumulative visual effects with Stroupster windfarm be considered.

LVIA cumulative assessment is set out with Section 6.11 of this chapter.

THC Assessment of visual effects should focus on key issues of human perception of visual effects.

Technical Assessment of effects on people at identified viewpoints is set out within section 6.6 of this chapter.

SNH SNH requested information on the justification and reasoning for the preference of steel lattice towers over wood trident poles should be provided.

The consideration given to design alternatives is set out within Chapter 4: Route Selection and Alternatives.

SNH Viewpoint selection should be agreed with SNH.

Viewpoint selection was confirmed in consultation with SNH on 28th November 2013 with reference to the draft ‘Bare Ground’ and ‘With Screening’ ZTVs.


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SNH Consideration of temporary construction accesses/ancillary works should be included.

Design parameters for construction works and ancillary works considered in assessment of effects on landscape resource and in effects on visual amenity are set out within Chapter 2: Description of the Development.

SNH Ensure most up-to-date information on windfarm context used in cumulative assessment.

The final, agreed list of other developments was confirmed with SNH and The Highland Council.

SNH Special Landscape Areas (SLA) – inclusion of Duncansby Head during assessment process.

A viewpoint location has not been included within the Duncansby Head SLA, as there is no theoretical visibility of the OHL within this area. (as shown on Figure 6.5).

SNH Consideration should be given to the Holford Rules, particularly Rule 6 in relation to flat and open character of the landscape.

Rule 6 (Technical Appendix 4.2) has been taken into consideration during the routing study process. Alternative tower designs and heights were considered for the western end of the proposed OHL, particularly in relation to the issue of visual confusion. The consideration given to design alternatives is set out within Chapter 4: Route Selection and Alternatives.

6.4 Assessment Methodology Baseline Characterisation

The principles of landscape and visual impact assessment have been established in the definitive series of guidance publications produced under the joint auspices of the Landscape Institute and Institute of Environmental Management and Assessment. A third edition of these has recently (2013) been published: “Guidelines for Landscape and Visual Impact Assessment 3rd Edition” Landscape Institute and Institute of Environmental Management and Assessment 2013 (GLVIA3) and this updated guidance is reflected in the methods outlined below.

The LVIA process includes the following key stages: • Definition of Study Area;

• Confirmation of Scope;

• Description of Baseline Conditions;

• Assessment of Likely Significant Effects;

• Design Input and Mitigation; and

• Reporting of Likely Significant Effects.

The stages are described in further detail, below.


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Definition of Study Area

The study area for the LVIA extends to include all areas from within which likely significant landscape and visual effects (as defined by EIA Regulations) are considered most likely to occur in relation to the specific type and scale of development concerned.

The study area, shown on Figure 6.1, was selected on a realistic and pragmatic basis with consideration given to the nature of the Proposed Development, the population distribution, settlement and communication patterns, the landscape and physiography of the surrounding area, the Zone of Theoretical Visibility (ZTV) mapping and observations made during site visits.

In accordance with SHE Transmission guidance2 and as confirmed with The Highland Council and SNH, a 10 km distance from the alignment of the Proposed Development was chosen, beyond which the Proposed Development was considered unlikely to result in significant adverse landscape and visual effects. Cumulative developments were considered out to 30 km from the Proposed Development (see section 6.11).

For construction effects related to the underground cable sections, ZTVs (both ‘bare ground’ and ‘with screening’ – see below) were generated for the area within 5 km of the alignment of the Proposed Development as it was considered unlikely that construction plant and activity would be noticeable to the casual observer beyond this distance.

Confirmation of Scope

A Scoping Opinion for the Proposed Development was sought from ECDU in December 2013. An updated scoping opinion was sought in April 2015, though no opinion was received from ECDU as of 21 July 2015. Therefore relevant issues for the scope were taken to be those included within the response from SNH are included in Table 6.1 above.

Nineteen viewpoints were agreed with The Highland Council and SNH on 2nd December 2013.

Other developments assessed under the cumulative assessment were confirmed with The Highland Council and SNH through the April 2015 scoping request.

Definitions

For the purpose of this assessment, the landscape resource is defined as: • 'The distinct spatial distribution, at a given moment in time, on the surface of the

earth, of the physical components resulting from the interaction between natural and human processes over time, and which produce consistently occurring patterns and homogeneity of landscape character and landscape context and how these are experienced and valued.'

Likewise, visual amenity is defined as:

2 Scottish Hydro Electric Transmission Limited (October 2004) Electricity Transmission Development Proposals in Scotland: A Guidance Document Outlining The SHETL Approach To The Routeing Of High Voltage Steel Lattice Tower Transmission Lines, Leading To An Application For Consent In Scotland


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• 'The assembly of components which provide an attractive visual setting or backcloth for activities.'

Both these definitions are consistent with those given in GLVIA3.

A desk study was undertaken to establish the existing baseline conditions of the landscape resource and visual amenity of the study area. Initial mapping of the Zone of Theoretical Visibility (ZTV) of the Proposed Development was undertaken along with identification of suitable candidate viewpoints for visual impact assessment, routes for sequential assessment, and other developments to be considered within the cumulative assessment was also undertaken.

Field survey work was subsequently undertaken, through December 2013 to March 2014, to verify the important landscape and visual characteristics of the area highlighted by the desk study, including confirmation of key visual receptors and viewpoints.

Landscape Baseline

The baseline landscape character assessment describes, classifies and analyses the character and sensitivity of the landscape within the study area, in order to establish the baseline landscape conditions. The aim is to identify and describe the key defining landscape features of local distinctiveness of particular areas that are likely to be affected by the Proposed Development.

Baseline landscape character has been described by reference to the Landscape Character Types identified in the existing published SNH assessment report: • ‘Caithness and Sutherland Landscape Character Assessment', SNH 1998.

Designated landscapes within the study area have been identified and are described in Section 6.5.

The key landscape receptors (the elements of the landscape that are likely to be affected by the Proposed Development) have been identified from the above descriptions and include: • overall landscape character and key characteristics;

• individual landscape elements or features; and

• specific aesthetic or perceptual qualities.

The scale of mapping to be used in the assessment process has been determined as 1:50,000, in accordance with ‘Landscape Character Assessment Guidance for England and Scotland’, 2002, Scottish Natural Heritage.

Visual Baseline

The baseline studies for visual amenity establish: • the area in which the development would be theoretically visible;

• the different groups of people who may experience views of the development (visual receptors);

• the viewpoints where they would be affected; and

• the nature of the views at those points.


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The key visual receptors are the people within the area who would be affected by the changes in views and visual amenity and include: • people living in the area (residents);

• people working in the area (on sea and land);

• people travelling through the area on roads or by rail;

• people visiting the area (including tourists); and

• people engaged in recreation.

Viewpoints which fall within the Zone of Theoretical Visibility (ZTV) and which are representative of these different groups of visual receptors have been identified and selected. They have been selected in accordance with criteria in GLVIA3 and agreed with The Highland Council and SNH. The selection criteria for viewpoints with the study area includes the following: • the full range of different types of views, including e.g. popular hilltops,

footpaths and other recreational routes, key transport routes, minor roads, settlements, cultural and recreational foci;

• viewpoints which are already important vantage points within the landscape, for example local visitor attractions, scenic routes, or places with cultural landscape associations;

• views from areas of high landscape or scenic value, including tourist routes and local amenity spaces;

• views from a range of distances, elevations and orientations, to enable assessment of a range of light conditions e.g. side-lit, back-lit and front-lit;

• sequential views along specific routes; and

• cumulative views.

Method of Assessment

Relevant sources consulted within this assessment were:

Guidance

• 'Guidance for Landscape and Visual Impact Assessment', The Landscape Institute and the Institute of Environmental Assessment third edition 2013 (GLVIA3);

• ‘Environmental Impact Assessment Handbook’, 4th Edition. Scottish Natural Heritage. 2005;

• 'Landscape Character Assessment for England and Scotland', Scottish Natural Heritage (SNH) and The Countryside Agency, 2002;

• ‘Assessing the Cumulative Impact of Onshore Wind Energy Developments’ SNH, 2012;

• ‘Visual Representation of Wind farms – Good Practice Guidance’, SNH, February 2007;

• ‘Use of Photography and Photomontage in Landscape and Visual Assessment’ - Landscape Institute Advice Note 01/11 as amended (March 2011);

• ‘Policy Statement No 02/03 – Wildness in Scotland's Countryside’, Scottish Natural Heritage, 2002; and


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• ‘Planning Guidance for the Preparation and Submission of Photographs and Photomontages to illustrate the impacts of Wind Energy Development for inclusion in Planning Applications and Environmental Statements’ The Highland Council, 2013.

Advice

• ‘A Handbook on Environmental Impact Assessment’, 3rd Edition. Scottish Natural Heritage. 2009; and

• ‘Effectiveness of Backcloth for Electricity Transmission Towers’, Version 1.0, Turnbull Jeffrey Partnership, 1993.

Background

• ‘Caithness and Sutherland Landscape Character Assessment', SNH 1998;

• OS 1:50,000 map sheets 11 and 12;

• ‘Assessment of Highland Special Landscape Areas’, The Highland Council, 2010; and

• ‘An Inventory of Gardens and Designed Landscapes: No. 3 Highland, Orkney and Grampian’, SNH 1997.

Zone of Theoretical Visibility Mapping

Zone of Theoretical Visibility (ZTV) identifies locations from which the Proposed Development would be theoretically visible. The ZTVs were modelled using a computer based visibility analysis package compiled using Ordnance Survey Digital Terrain Model (DTM) data at 50 m interval resolution.

ZTV maps, based on Digital Terrain Model (DTM) data, give a good indication of the broad areas from which existing features and proposed developments may be seen, and are useful as a tool for informing the landscape character and visual assessment. However, they also have a number of limitations as listed below: • a ZTV can only indicate theoretical visibility;

• areas of likely visibility identified on ZTV plans require site verification to establish if specific site features would limit or prevent visibility of the Proposed Development;

• a ZTV’s accuracy is limited by the data available to create it; most importantly, the accuracy of this is limited by the DTM data, which cannot distinguish below a certain level of detail and is limited by the need for software to interpolate between the heights at survey points;

• correlation of areas of theoretical visibility with the likelihood of the presence of people is required to establish the likelihood of views being experienced from these areas; and

• a ZTV does not indicate likely visual effects, nor the significance of these.

As a result of these limitations, it is acknowledged that ZTVs can overestimate the actual extent of visibility of a proposed development within a particular area. Consequently, the ZTVs should be used only as a tool to assist in assessing the theoretical visibility of a development and not as a measure of its visual effect.

‘Bare Ground’ ZTVs take no account of the screening effects of urban areas, buildings, structures or vegetation and therefore present a worst-case scenario.


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‘With Screening’ ZTVs take into account screening effects of urban areas, buildings and areas of woodland but do not take into account the local screening effects of scrub vegetation, garden walls, fences and detailed localised changes in ground level.

A ‘Bare Ground’ ZTV has been generated to identify the likely extent of visibility of the OHL elements of the Proposed Development over the 10 km distance from the Proposed Development. A draft version of this ZTV was used in viewpoint selection for visual impact assessment.

A ‘With Screening’ ZTV has also been generated to identify the likely extent of visibility of the Proposed Development over the 10 km radius study area, taking into account screening factors. The ‘With Screening’ ZTV has been used for the purpose of this assessment, to take account of areas of forestry in proximity to the Proposed Development at certain points along its length.

ZTVs were also produced for the construction activities associated with underground cable installation based on the likely installation method described in Chapter 2: Description of the Development.

Wireline images were generated, to assist in the assessment of visual effects, also using a computer based visibility analysis package. Photomontages have also been produced where appropriate.

Viewpoint Photography

Photographs were taken from each agreed viewpoint (on successive field visits), using a Canon EOS 5D Digital Single Lens Reflex (SLR) camera with a Canon EF 50 mm lens mounted on a panoramic Manfrotto 303 plus tripod set to 25 degree intervals for landscape shots and 15 degree for portrait. Photography and visualisations accord with SNH 2006 guidance Scottish Natural Heritage (2006): Visual Representation of Windfarms. Good Practice Guidance. 29 March 2006. And where possible, with The Highland Council’s revised ‘Visualisation Standards for Wind Energy Developments’, 2013.

Assessment of Likely Significant Effects

Definitions

‘Impact’ is specific and defined as the action being taken, for example, cutting down trees.

‘Effect’ is defined as the change resulting from that action.

When identifying likely significant effects, all types of effect, such as positive/beneficial and negative/adverse, should be included. As stated in GLVIA3, ‘identifying significant effects stresses the need for an approach that is in proportion to the scale of the project that is being assessed and the nature of its likely effects. Judgement needs to be exercised at all stages in terms of the scale of the investigation that is appropriate and proportional.’

The result of the assessment is the determination of whether the likely effect of the Proposed Development on the landscape resource and visual amenity in the study area would be significant or not significant, and adverse or beneficial.


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The assessment of likely effects includes: • identification and evaluation of likely landscape effects. Landscape effects are

effects on landscape as a resource and affect landscape receptors as defined in the baseline study; and

• identification and evaluation of likely visual effects. Visual effects are effects on views and visual amenity as experienced by people and affect visual receptors as defined in the baseline study.

Sequential Impact Assessment

Sequential effects on visibility occur when an observer moves along a linear route, and as a result is able to see other developments, or a different view of the same development.

Routes including roads, railways and cycle routes have been examined via desk based study to assess likely sequential effect. These receptors were agreed with The Highland Council. Baseline conditions were established by travelling each route. Theoretical visibility for each route has been measured based on the ZTV map to determine the amount of time the Proposed Development would be theoretically visible for travelling both ways along each linear route. The assessment takes into account the various distances from which the Proposed Development would be likely to be seen.

Cumulative Impact Assessment

Cumulative impacts can be defined as the additional changes caused by a Proposed Development in conjunction with other similar developments or as the combined effect of a set of developments, taken together.

In the absence of specific guidance relating to consideration of cumulative effect of OHLs, cumulative impact assessment methodology developed for wind farms (‘Assessing the Cumulative Impact of Onshore Wind Energy Developments’ SNH, 2012) is considered of some relevance.

All wind energy schemes granted permission for infrastructure over 50 m in height;, which are currently the subject of undetermined applications; or which have been refused and are subject of Appeal and which lie within 60 km of a proposed development would normally be considered in a cumulative assessment.

As the ZTV for the Proposed Development is only a 10 km, it is considered that a cumulative development, 60km distance is unlikely to give rise to significant cumulative effect. This assessment has therefore considered only those other developments located within 30 km of the Proposed Development, unless further developments are specifically requested by The Highland Council/SNH. This is due to the potential for cumulative effects to arise for viewers at static viewpoints (where they could see both the OHL and theoretically another development with visibility from a greater distance – for example a wind farm), and for viewers moving through the landscape, who may see several wind farms along a route and also the OHL.

The list of other developments to be considered as part of the cumulative assessment was agreed with The Highland Council and SNH as set out within Chapter 3.


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The LVIA methodology is summarised in the flow diagram above.

Identify and describe the changes and likely effects, and for each effect:

Combine to judge magnitude of effect: Severe Major Moderate Minor Negligible Refer to Tables 6.3 and 6.5

Combine to assess significance of effects

Refer to Table 6.6

Final Statement of likely significant effects

Refer to Table 6.7

Define scope of assessment:

Study Area

Range of people and places that may be affected

Describe characteristics of the proposal

Refer to Chapter 2

Establish Environmental Baseline

Refer to Section 6.5

Identify receptors

Summary of Methodology for the Assessment of Landscape and Visual Effects

Combine to judge sensitivity of receptor: Very High High Medium Low Negligible

Refer to Tables 6.2 and 6.4

Judge reversibility of change

Judge duration of change

Judge size/scale of change

Judge susceptibility of receptor to specific change

Judge value attached to receptor

Propose measure to mitigate adverse effects

Refer to section 6.7

Identify interaction between proposal and receptors

Refer to Section 6.6


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Significance Criteria

Landscape Sensitivity to Change

The relative sensitivity of the landscape character within each character area, together with areas of landscape designation, is specific to the proposed change and is assessed in terms of two sets of criteria (GLVIA3): • Susceptibility to the change; and

• Value of the receptor.

For the purposes of this assessment the following definitions have been applied as noted in Table 6.2 below. It is stressed that in the assessment of a specific receptor, the actual criteria applied may differ from the Typical Criteria noted below. In all cases a clear explanation of the reasons for the judgement of sensitivity is given.

Table 6.2: Definitions of Landscape Sensitivity

Sensitivity of receptor

Typical Criteria

Very High Susceptibility to Proposed Change: • landscapes of very high quality and condition: with consistent, intact, well-

defined, and distinctive attributes, well-managed, in exceptional state of repair; and

• none of the key characteristics of the landscape relate well to the proposed development.

Value: • landscapes located within and which contribute to the value of landscapes

designated at national and/or international level: e.g. designated National Scenic Area, National Park, World Heritage Site;

• landscapes with a very high degree of relative wildness; and • landscapes where there is evidence of very high value associated with

natural heritage, recreational activity, cultural associations, or other special interests.

High Susceptibility to Proposed Change: • landscapes of high quality and condition; and • few of the key characteristics of the landscape relate well to the proposed

development. Value: • landscapes located within and which contribute to the value of landscapes

designated or recognised at regional or local level e.g. Historic Gardens and Designed Landscapes and Special Landscape Areas;

• landscapes with a high degree of relative wildness; and • landscapes where there is evidence of high value associated with natural

heritage, recreational activity, cultural associations, or other special interests.


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Table 6.2: Definitions of Landscape Sensitivity

Sensitivity of receptor

Typical Criteria

Medium Susceptibility to Proposed Change: • landscapes of moderate quality and condition; and • some of the key characteristics of the landscape relate well to the

proposed development. Value: • landscapes may be locally valued but with no explicit designation or

recognition of value; • landscapes dominated by agricultural or other man-modified land uses,

although with some degree of relative wildness; and • landscapes where there is evidence of some value associated with natural

heritage, recreational activity, cultural associations, or other special interests.

Low Susceptibility to Proposed Change: • landscapes of low or poor quality and condition, attributes poorly-managed,

in poor condition and state of repair; • settled landscapes, with complex land use patterns where built elements

and structures are already a strong part of the landscape character; and • landscape intrinsically able to accommodate proposed change with many

of the key characteristics relating well to the proposed development, or unlikely to be diminished.

Value: • landscapes with few specific features of natural heritage, cultural

associations, or other special interest.

Negligible Susceptibility to Proposed Change: • heavily developed, industrial landscapes; • landscapes of very low or very poor quality and condition, attributes very

poorly-managed, in very poor condition and state of repair; and • none of the key characteristics are likely to be diminished by the proposed

change. Value: • landscapes with no specific features of natural heritage, cultural

associations, or other special interest.

Magnitude of Landscape Change

The magnitude of change to landscapes is assessed in terms of three sets of criteria (GLVIA3): • size or scale;

• geographical extent; and

• duration and reversibility.

For the purposes of this assessment the following definitions have been applied as noted in Table 6.3 below. It is stressed that in the assessment of a specific receptor, the actual criteria applied may differ from the Typical Criteria noted below.


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In all cases a clear explanation of the reasons for the judgement of magnitude will be given.

Table 6.3: Definitions of Magnitude of Landscape Change

Magnitude of Change

Definition

Severe Size or Scale: • very high proportion of landscape unit affected; • very high proportion of landscape elements affected; and • Complete loss of, or fundamental change to, the key characteristics of the

landscape. Geographical Extent: • very large number of LCTs affected throughout the study area; very large

area affected of the LCT(s) within which the development would sit; fundamental change to the immediate setting; fundamental change to the site of the proposed development.

Duration and reversibility: • permanent change to landscape; and • change not reversible.

Major Size or Scale: • high proportion of landscape unit affected; • high proportion of landscape elements affected; and • substantial change to key characteristics of landscape.

Geographical Extent: • large number of LCTs affected in the majority of the study area; large area

affected of the LCT(s) within which the development would sit; considerable change to the immediate setting; considerable change to the site of the proposed development.

Duration and reversibility: • long term change to landscape (25 or more years); and • change difficult to remove or reinstate.

Moderate Size or Scale: • Moderate proportion of landscape unit affected; • Moderate proportion of landscape elements affected; and • Material change to key characteristics of the landscape.

Geographical Extent: • Several LCTs affected over part of the study area; medium area affected of

the LCT(s) within which the development would sit; noticeable change to the immediate setting; noticeable change to the site of the proposed development.

Duration and reversibility: • Medium term change to landscape (5-24 years); and • Change that can be partially removed or reinstated.


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Table 6.3: Definitions of Magnitude of Landscape Change

Magnitude of Change

Definition

Minor Size or Scale: • small proportion of landscape unit affected; • small proportion of landscape elements affected; and • discernible changes to key characteristics of the landscape.

Geographical Extent: • few LCTs affected over a small part of the study area; small area affected

of the LCTs(s) within which the development would sit; insignificant change to the immediate setting; insignificant change to the site of the proposed development.

Duration and reversibility: • short term change to landscape (up to 5 years); and • change that can be fully removed and reinstated.

Negligible Size or Scale: • changes which are not readily discernible or have no effect on the integrity

of landscape elements or landscape unit. Geographical Extent: • very few LCTs affected over part of the study area; very small area

affected of the LCTs (s) within which the development would sit; imperceptible change to the immediate setting; imperceptible change to the site of the proposed development.

Sensitivity of Visual Receptors to Change

All visual receptors are people. The relative sensitivity of the visual receptors is specific to the proposed change and is assessed in terms of two sets of criteria (GLVIA3): • susceptibility of visual receptors to the proposed change; and

• value attached to views experienced by receptors.

For the purposes of this assessment the following definitions have been applied as noted in Table 6.4 below. Note that in the assessment of a specific receptor, the actual criteria applied may differ from the guide criteria noted below. In all cases a clear explanation of the reasons for the judgement of sensitivity will be given.


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Table 6.4: Guide Criteria of Visual Sensitivity

Sensitivity of Receptor

Guide Criteria

Very High Susceptibility to Proposed Change: • users of strategic outdoor recreational facilities (including national long

distance footpaths, national cycle routes); • visitors to important mountain summits, landmarks, heritage assets or

other attractions, where views are an essential contributor to the experience; and

• residents at home with views of the development (where agreed with the Planning Authority).

Value Attached to Views: • very high value placed on the View: e.g. celebrated viewpoint included in

tourist guides, view located within a landscape designated at national or international level.

High Susceptibility to Proposed Change: • users of outdoor recreational facilities (including local Core Paths and other

recreational footpaths, cycle routes or rights of way); • special interest groups to whom landscape setting is important; and • residents of communities/settlements where views are an important

contributor to the landscape setting enjoyed by residents in the area. Value Attached to Views: • high value placed on the View: e.g. recognised viewpoint marked on maps,

views within landscapes designated at regional or local level, views from recognised scenic routes/designated tourist routes, views of (or from) landscape or built features with important physical, cultural or historic attributes; and

• view protected at local or regional level by Development Plan.

Medium Susceptibility to Proposed Change: • people engaged in outdoor sports or recreation where appreciation of the

landscape setting contributes to the experience; • people at places of work, whose attention may be focused on their activity

rather than the wider landscape, but where the setting is recognised as an important contributor to the quality of working life; and

• travellers on road, rail, ferry or other transport routes. Value Attached to Views: • some evidence of value placed on view, view may contribute to setting of

activity.

Low Susceptibility to Proposed Change: • people at places of work, whose attention may be focused on their activity

rather than the wider landscape; and • people engaged in outdoor sports or recreation which does not involve or

depend on appreciation of views of the landscape. Value Attached to Views: • no evidence of value placed on view.


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Table 6.4: Guide Criteria of Visual Sensitivity


Guide Criteria

Negligible Susceptibility to change of viewers and value attached to views are of a level not considered relevant to the assessment.

Magnitude of Change to Views and Visual Amenity

The magnitude of change to views and visual amenity experienced by the receptor is assessed in terms of three sets of criteria (GLVIA3): • size or scale;

• geographical extent; and

• duration and reversibility.

For the purposes of this assessment the following definitions have been applied as noted in Table 6.5. It is stressed that in the assessment of a specific receptor, the actual criteria applied may differ from the guide criteria noted below. In all cases a clear explanation of the reasons for the judgement of magnitude will be given.

Table 6.5: Guide Criteria for Magnitude of Visual Change

Magnitude of Change

Guide Criteria

Severe Size or Scale: • proposed change would define view; • all of development visible; • very strong contrast with key visual characteristics of the baseline view e.g.

scale, horizontality, composition; and • duration of view long, view studied/enjoyed for considerable time.

Geographical Extent: • angle of view to development directly coincides with focus of receptor

activity/viewpoint/road alignment, etc.; • very short distance from viewpoint to development; and • development occupying the majority of the view.

Duration and Reversibility: • permanent change to view; and • change not reversible.


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Magnitude of Change

Guide Criteria

Major Size or Scale: • development would be the dominant feature in the view; • high proportion of development visible, no significant screening effects; • strong contrast with key visual characteristics of the baseline view e.g.

scale, horizontality, composition; and • duration of view not curtailed by physical parameters.

Geographical Extent: • angle of view to development coincides with focus of receptor

activity/viewpoint/road alignment, etc.; • short distance from viewpoint to development; and • development occupying a high proportion of the view.

Duration and Reversibility: • long term change to view (25 or more years); and • change difficult to remove or reinstate.

Moderate Size or Scale: • development would be a noticeable component of the view; • development partially screened by topography, vegetation, etc.; • some conflicts with key visual characteristics of the baseline view e.g.

scale, horizontality, composition; and • duration of view relatively short. Time to absorb or contemplate view

curtailed by physical parameters. Geographical Extent: • angle of view to development does not coincide with focus of receptor

activity/viewpoint/road alignment, etc.; • moderate distance from viewpoint to development; and • development occupying part of the view.

Duration and Reversibility: • medium term change to view (5-24 years); and • change that can be partially removed or reinstated.


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Magnitude of Change

Guide Criteria

Minor Size or Scale: • development is a minor component of view; • development substantially screened by topography, vegetation, etc.; • development compatible with key visual characteristics of the baseline view

e.g. scale, horizontality, composition; and • duration of view short or transient. Glimpse or interrupted views.

Geographical Extent: • angle of view predominantly away from development; • long distance from viewpoint to development; and • development occupying a small part of the view.

Duration and Reversibility: • short term change to view (up to 5 years);and • change that can be fully removed and reinstated.

Negligible Changes which are not discernible to the casual observer.

Environmental Consequence: Likely Landscape and Visual Effects

The sensitivity of the receptor and the magnitude of change are combined to assess the significance of effect with reference to the matrix, below in Table 6.6.

It is important to note that with regard to landscape and visual effects, this matrix has been used as a guide only. The matrix is not used as a prescriptive tool, and the analysis of specific effects must make allowance for the exercise of professional judgement. Therefore, in some instances, a particular parameter may be considered as having a determining effect at the expense of the matrix.

Table 6.6: Guide for Determination of likely Landscape and Visual Effect

Sensitivity Very High High Medium Low Negligible

Magnitude

Severe Severe Minor

Major

Moderate

Minor

Negligible Minor Negligible


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Nature and Significance of Likely Landscape and Visual Effects

Determination of the nature of the effect is essentially a matter of judging whether the key landscape or visual characteristics are strengthened, weakened or not affected as a result of any changes brought about by the Proposed Development. Therefore, the effect of a proposed development can be adverse/negative or beneficial/positive, or there can be no effect.

The following system of categorisation is used for the nature of the effect: • Adverse: key characteristics of the landscape or quality of the visual experience

weakened by the introduction of the Proposed Development.

• Neutral/No Effect: key characteristics of the landscape or quality of the visual experience not affected by the introduction of the Proposed Development.

• Beneficial: key characteristics of the landscape or quality of the visual experience strengthened by the introduction of the Proposed Development.

Wherever possible, identified likely effects are quantified, but the nature of landscape and visual assessment requires interpretation by professional judgement.

The significance of likely effects is measured on a seven point scale as detailed in Table 6.7 below.

Table 6.7: Significance of Likely Effect

Consequence of Effect Significance under EIA Regulations

Severe Significant Intolerable risk and /or significance. Impacts to be avoided where ever possible.

Major Significant Highly significant and requires immediate action. Impacts to be avoided rather than managed.

Moderate Significant Requires additional control measures and/or active management.

Minor Not Significant May require some management to ensure any effect remains within acceptable levels.

Negligible Not Significant Difficult to detect or measure.

Neutral No significance. No action required.

Beneficial Positive. To be encouraged.

EIA Regulations require judgment of the acceptability of a scheme to occur in the full knowledge of the likely significant effects of the proposal on the environment. However, GLVIA explains that “in the context of EIA, however, ‘significance’ varies with the type of project and the topic under assessment” and “it may be helpful to


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define levels or categories of significance (including ‘not significant’) appropriate to the nature, size and location of the proposed development”. To satisfy these requirements, this assessment considers that, where likely landscape or visual effects of moderate, major or severe level are identified, these should be considered as a significant effect.

Design Input and Mitigation

Design and assessment are part of an integrated, iterative process where one influences the other. The ongoing assessment of likely environmental effects is regarded as an integral part of the design process. Design iteration and mitigation has been informed iteratively by on-going assessment of likely landscape and visual effects, resulting in an optimised design solution. The design process resulting in the Proposed Development is described in Chapter 4: Route Selection and Alternatives.

Reporting of Likely Significant Effects

The ES sets out the identified likely significant effects of the Proposed Development on the study area. These have been based on the final scheme layout, taking into account any relevant mitigation proposals.

6.5 Baseline Conditions Current Baseline - Landscape

Landform

The Proposed Development is located to the south-east of Thurso, extending from the Thurso South substation, currently being constructed, over the A9, and east and north-east towards Gills Bay, terminating at the proposed Gills Bay substation. The OHL element of the Proposed Development starts, in the west in the vicinity of Weydale, at approximately 40 m Above Ordnance Datum (AOD), climbing around the south of Hill of Olrig to approximately 100 m AOD, before descending over gently undulating topography towards Gills Bay.

The landform of the study area is relatively low lying, typically around 40 m AOD, with the highest points lying to the west, notably Spittal Hill, Hill of Olrig, Dunnet Head, Hill of Forss and Hill of Lieurary. The highest, Spittal Hill, reaches 176 m AOD. Warth Hill forms the highest elevation to the east, at 124 m AOD. The lowest lying topography, below 20 m AOD, is found along the coast and along watercourses, which typically trend south-east - north-west. The Forss Water, the River Thurso and the River Wick are the main watercourses within the study area, with Loch Calder, Loch Scarmclate, Loch Watten, St John’s Loch, Loch Heilen and Loch Mey forming the main waterbodies.

The coast to the north is characterised by low rocky cliffs and marine platforms interspersed with small sandy beaches and bays, including Thurso Bay, Murkle Bay, Dunnet Bay, Gills Bay, Ness of Duncansby, Freswick Bay and Sinclair’s Bay. Coastal features such as skerries, sea stacks and ravines (Geos) also occur.

Land Use and Landscape Pattern

Land use in the study area comprises a mosaic of improved and semi improved grassland, rough grazing, moorland, and commercial forestry plantations, which are usually of a single species and uniform dark colour. Occasional hedgerows


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and isolated groups of wind pruned deciduous trees are also characteristic features of the study area. Fields are generally quite large and bounded by post and wire fences, traditional dry stone dykes or the distinctive Caithness flagstone fences. In some locations, roadside hedges have been established alongside the field divisions.

Man Made Elements

The study area is characterised by concentrated and scattered settlement, isolated dwellings and farmsteads. The key small settlements in the study area include Thurso, Halkirk, Castletown, and John O’Groats.

Currently, two operational, single wind turbines exist within the study area, one at Crossroads Primary School (12.7 m to tip height) and one south-east of Mey Village Hall (20 m to tip height).

Other prominent vertical man-made features in the study area include telecommunication and radio masts, steel lattice OHL towers (in the west of the Study Area) and wood pole mounted overhead lines.

The main transport routes through the study area are the A9, the A882, the A836, the A99, the B855, the B874, the B870, and the B876, linked to a network of minor local roads and single track roads.

National Cycle Network (NCN) Route 1 runs inland parallel to the coast east-west across the study area.

The Inverness to Thurso/Wick railway lines dissect the study area to the west.

The Northern Isles ferry arrives and departs from the harbour at Scrabster and the Gills Bay ferry arrives and departs from the pier at Gills Bay.

Change in the Past

The most notable landscape changes of the study area in the past have resulted from the afforestation of tracts of former moorland, and from the opening up of the area to built development by means of the network of roads and tracks.

Existing wind farm development is also a notable change from the past within the wider landscape including Flex Hill, Achairn, Camster, Wathegar and Causeymire just outwith the southern boundary of the study area, Baillie Hill and Forss just outwith the western boundary, and a host of smaller, single turbines scattered throughout the study area. These developments are taken into account in the baseline description of the landscape resource and visual amenity.

Landscape Character

SNH’s 'Caithness and Sutherland Landscape Character Assessment', 1999 (LCA) describes nine Landscape Character Types (LCTs) within the study area. These are mapped on Figure 6.2. The key characteristics and the sensitivity of these LCTs to accommodate the type of development proposed, as defined in the LCA, are described in Table 6.9 below.

The LCA also defines and maps areas of ‘Coastal Island’, ‘Coniferous Woodland Plantation’, ‘Inland Lochs’ and ‘Loch Island’, but does not describe their key characteristics in any detail. The LCA assumes that these areas are landscape


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features rather than LCTs, and therefore does not include these areas in the assessment, although detailed reference is made to them where relevant in specific assessments of LCTs which abut or contain these areas.


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Table 6.8: Description of Landscape Character Types

LCTs (Total area within the study area)

Landform Land Use and Landscape Pattern Man-made Features SNH guidance – where provided

Number of incidences of LCT in the study area/ Percentage coverage of entire study area/ Percentage coverage of study area excluding the sea. Presence or absence of landscape designations

Sweeping Moorland (102.90 km2)

• Wide open and flat landscape • Gently sloping or undulating

landforms eroded by watercourses to form shallow glens

• Predominantly grouse and upland species, lacking in distinctive features

• Influenced by weather and light conditions

• Punctuated by watercourses - lochs, juvenile streams, and mature, meandering rivers

• Peatland, coarse, damp and mossy vegetation cover

• Ribbons of broadleaf woodland • Coniferous plantations • Pockets of improved grazing land

• Ruined buildings • Field boundaries and drainage

channels • Small settlements • Estates • Roads, rail, vehicle tracks and

wheel markings • Power lines • Peat cuttings and hagging • Grouse management

• Vertical elements visually intrusive from a considerable distance

• Little scope for screening • Fragile ecosystems and remote

sense of place • Sense of open space could absorb

scale of development

• 9 instances • 18.12% of study area excluding the

sea • Designations: • Dunnet Head SLA • Duncansby Head SLA

Flat Peatland (28.35 km2)

• Flat or gently undulating • Vast openness on plateau •

• Dominance of sky with extreme exposure and panoramic visibility

• Few visual foci except distant hills on horizon

• Water forms a dominant element with lochs, water channels, dubh lochans, and wet, spongy vegetation

• Cloths of coniferous plantation • Inhabited by distinct flora and

fauna (esp. insects and birds)

• Historic features • Snow barriers • Rail


• New structures can dilute the simple character of this landscape

• Little scope for screening • Fragile ecosystems and remote

sense of place • Sense of open space could absorb

scale of development •

• 1 incidence • 4.99% of study area excluding the

sea • Designations: • none

Open Intensive Farmland (19.35 km2)

• Wide plain of simple ordered landscape

• Open and flat or gently undulating

• Extreme exposure and extensive visibility

• Smooth, open sky above agricultural land

• Ordered pattern of fields • Shelterbelts and hedgerows • Wetlands and lochs

• Roads and access tracks • Fence lines and dykes • Buildings • Historic features • People and machinery • Large commercial farms • Estate properties

• New structures can relate to pattern of landscape

• Vertical elements would be highly visible in the open landscape

• Sense of open space could absorb scale of development

• 7 incidences • 3.41% of the study area excluding

the sea • Designations: • Castle of Mey GDL


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Mixed Agriculture and Settlement (327.32 km2)

• Gently sloping landform • Low hills, basins and shallow glens

• Wetland • River, loch • Grassland and bracken • Arable fields and rough grazing • Mature broadleaf and mixed

woodland • Rich habitat for birds

• Ruined crofts • Dykes and stone walls • Flagstone fences • Settlements and isolated

villages/housing estates • Isolated 'kit' housing • Estate properties • Roads and power lines • Historic features

• Complex mix of landscape elements with dynamic quality makes it difficult to locate a new development in relation to existing land patterns

• Could cause visual confusion • Character of landscape suggests

strong sense of change thus better accommodating future developments

• 6 incidences • 57.63% of study area excluding the

sea Designations: • Dunnet Head SLA

Small Farms and Crofts (34.35 km2)

• Variable • Moorland or coastal areas

• Open moorland • Fragments of broadleaf woodland • Woodlots • Single trees • Cultivated fields and grazing land • Grassland • Coastal areas/harbours • Open space and dominance of sky • Rough grassland • Grazing land

• Ordered crofts • Open and fairly rich, small farms • New 'kit' housing/holiday homes • Ruined properties • Roads and access tracks • Fences, walls • Power lines • Machinery • Local facilities • Sparse habitation • Croft ruins • Ancient structures

• Complex mix of landscape elements with dynamic quality makes it difficult to locate a new development in relation to existing land patterns

• Could cause visual confusion



High Cliffs and Sheltered Bays (1.15 km2)

• Long stretches of high cliff interrupted by the location of a bay

• Strong linear edge

• Dominated by sea/land edge • Stacks, caves, pebbles, and

collapsing cliffs • Sandy, sheltered bays • Short mat of vegetation - grazing

and walking • Soaring and nesting seabirds • Wandering sheep

• Rigs, boats • Prominent cliff top buildings -

lighthouse • Harbours • Roads and tracks • Small settlements and local

facilities • Car parks and tourist/visitor

facilities


• Little scope for screening • Would cause visual confusion and

conflict with existing elements and character

• Would remove focus and status of certain focal features


sea Designations: • Duncansby Head SLA


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Long Beaches, Dunes and Links (3.27 km2)

• Soft linear edge with smooth surface and gentle curve

• Wide open space with extensive visibility and exposure

• Simple composition of sky/sea/land • Inter-relationship between sea,

weather and light patterns create dynamic landscape

• Exposed sand dunes and marram grass

• Areas of short grazed and trampled grass

• Wetland and scrub occasionally in hollows

• Edge of beach often covered by woodland or merging into rich agricultural land

• Seabirds are intrinsic characters

• Golf links • Recreational landscape - walkers • Visitor facilities • Camp and caravan sites • Hotels and B&B's • Settlements • Roads, rail, and airstrips • Industrial units

• Sense of open space could absorb scale of wind farm

• Little scope for screening • Could cause visual confusion and

conflict with existing elements and character

• May conflict with open and remote sense of place



Harbour (0.33 km2)

• Located where a glen intersects the coastline or at the edge of a bay

• Partly enclosing slopes

• Wooded slopes result in a favourable microclimate and sense of shelter

• Predominantly man made

• Focus within its surroundings comprising an area of concentrated buildings

• Residential, industrial and service related

• Elements arranged around harbour walls that contain deep waters

• Busy activity both land and sea based

• Complex land use • Built elements and structures form

strong part of landscape character


sea Designations: • none

Town (11.86 km2)

• Variable • Positioned near to the sea or river

estuary

• Built form • Human activity • Complex and experiential core

radiating out to less dense character or

• Variable core with 'out of town' facilities

• Woodland, parkland and common ground

• Roads, footpaths • Buildings • Walls, fences • Signs and lighting • Car parks and cars • Tourist facilities

• Complex land use • Built elements and structures form

strong part of landscape character


sea Designations: • none


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Landscape and Scenic Designations

Landscape Designations within the study area are shown on Figure 6.3.

Special Landscape Areas (SLAs)

An SLA is a non-statutory conservation designation used by The Highland Council to categorise sensitive landscapes which are, either legally or as a matter of policy, protected from development or other man-made influences. Given the local and regional importance of SLAs, these will be judged as having a medium sensitivity to change.

There are two SLAs located within or on the edge of the study area as set out in Table 6.9 and discussed below:

Table 6.9: Landscape Designations

Site Location

Approximate distance to nearest section of OHL

Total Area

% of area within Study Area

Dunnet Head SLA Centrally, to the north of the study area, overlapping with the study area boundary

7 km 23.5 km2 80.25%

Duncansby Head SLA

Eastern boundary of study area with only a small portion located within the Study Area

10 km 9 km2 5.4%

Dunnet Head SLA occupies a relatively small portion of the central northern section of the study area (approx. 18.85 km2) and is described in the following extract from The Highland Council’s Assessment of Highland Special Landscape Areas report, 2011.

‘This area includes the most northerly point on mainland Britain. The peninsula is characterised by its prominent headland, striking vertical cliffs and expanse of isolated moorland. Dunnet Head juts out into the Pentland Firth, so that experience at its northern tip is one of being more at sea than on land. To the south, settled farmland and a fine sandy beach and dune system provide a contrasting landscape experience. Clear weather allows impressive and extensive views over land and sea to Orkney, Strathy Point, Cape Wrath, Duncansby Head and the distinctive range of hills within the flow country, including the peaks of Morvern, Maiden Pap and Scaraben to the south.’

The special qualities of Dunnet Head SLA are identified as: • panoramic views from prominent headland and striking cliffs;

• isolated moorland and lochans; and

• contrasting bay and cliff landscapes.

Duncansby Head SLA occupies a very small portion of the study area along the eastern boundary (approx. 0.48 km2) and is described The Highland Council’s Assessment of Highland Special Landscape Areas report, 2011 as follows:


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‘Forming the most north-easterly point on mainland Britain, the headland is notable for its spectacular cliff scenery and its commanding views. Huge populations of seabirds use the cliffs as a breeding ground in spring providing a distinctive experience of bird noise and activity.’

The special qualities of Duncansby Head SLA are identified as: • commanding views and ‘End of Road’ experience; and

• striking and diverse coastal landforms.

The citation extracts from the Assessment of Highland Landscape Areas report for the two SLAs are provided in Technical Appendix 6.1.

Gardens and Designed Landscapes

An Inventory of Gardens and Designed Landscapes (GDLs) in Scotland identifies, in five volumes, specific gardens and designed landscapes of importance in terms of their artistic, historical, architectural, scenic and nature conservation value. Additional volumes identify Candidate Sites, which are considered worthy of inclusion in the Inventory. Planning policies generally provide a framework for the continued protection, conservation and use of these areas that does not prejudice their scenic or cultural value in accordance with national policy. Historic Scotland also provides a wide range of web-based information on these sites which has been used to establish the current baseline information on which to undertake the assessment of impact.

Reference to the Inventory indicates one GDL, Castle of Mey, lies within the study area to the north of the Proposed Development. It is included in the inventory for the following reason: ‘Of outstanding historical value due to its association with the Royal Family and the Earls of Caithness, the designed landscape of Castle of Mey provides the setting for a category A listed castle and makes a major contribution to the surrounding scenery. The designed landscape of parkland, woodland, formal gardens and walled gardens, probably established in the early 19th century and improved in the latter half of the 20th century, embellishes the magnificent setting of the Castle of Mey.’

The Inventory lists the importance of this GDL as follows: • Works of Art – Some

• Historical – Outstanding

• Horticultural, Arboricultural, Silvicultural – Some

• Architectural – Outstanding

• Scenic – Outstanding

• Conservation – Some

The Inventory describes the location and setting as follows: ‘The Castle of Mey is situated on the north coast of Scotland approximately 5 miles (8 km) west of John O'Groats, and 15 miles (24 km) east of Thurso. The lands of Mey lie on the flat coastal plain of Caithness and are extremely exposed to the harsh climate and winds which blow off the Pentland Firth. The surrounding landscape is predominantly pasture land and there are few trees. Magnificent views can be gained west to Dunnet Head, the most northerly point of Scotland,


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and across the Pentland Firth to the Orkney Islands. The Castle and its woodlands are significant from the A836 and other minor roads between it and the coast, particularly from the east. The flat nature of the surrounding landscape limits views of areas covered by the policies which are enclosed within the woodlands to the south and the policy walls to the north.

The Castle of Mey commands a magnificent position some 500 yards from the shore of the Pentland Firth. The designed landscape extends south to the lodge, west to the edge of the walled garden and the woodlands flanking the west drive, and east to Barrogill Mains farm. To the north, a road links the Castle with a road running west to the pier at Harrow, approximately 1 km to the west of the Castle. To the south, a road runs due south from the lodge flanked by a beech/hawthorn hedge and a stone dyke to the A836. A shelterbelt has been established along the northern edge of the A836, but this is not part of the Castle of Mey property.

The designed landscape includes some 100 acres (40.5ha) of parkland, 11.64 acres (4.7 ha) of woodland, and 2.68 acres (1.08 ha) of formal garden which includes 1.25 acres (0.5 ha) of walled gardens.’

Wild Land Areas

There are no Wild Land Areas within the study area and as the relative wildness value of the study area is categorised as low, an assessment on the likely effects on wild land has not been included within this assessment.

Current Baseline Conditions - Visual Amenity

This visual assessment has been undertaken by landscape architects trained in visual impact assessment and specifically looking for the Proposed Development within specific views, and in conditions of good visibility, which is defined by the Meteorological Office as equating to when an observer can see further than 9.26 km. The visual assessments are therefore intended to represent a ‘worst case’ scenario of the likely effect of the Proposed Development on visual amenity.

The visual amenity of the study area relates to the landscape characteristics described above.

Zone of Theoretical Visibility (ZTV)

The ‘Bare Ground’ ZTV, as shown on Figure 6.4 (OHL) and Figure 6.4.1 (for construction activities associated with the underground cable), demonstrates theoretical visibility over a moderate portion of the study area; 436.54 km2 within the 746 km2 study area, equating to 58.52%. However, excluding coverage over the sea, the ZTV covers approximately 363 km2, equating to 63.94% of the land based portion of the Study Area. This ZTV takes no account of the potential screening effect of existing buildings or vegetation, and therefore represents a ‘worst-case’ scenario.

The ‘with Screening’ ZTV, as shown on Figure 6.5 (OHL) and Figure 6.5.1 (underground cable), demonstrates theoretical visibility over a smaller portion of the study area; 375.9 km2 within the 746 km2 study area, equating to 50.39%. Excluding coverage over the sea, theoretical visibility is shown over 53.51% of the land based portion of the study area. The ZTV takes account of existing buildings (at 8 m) and existing vegetation (at 12 m) and represents a more realistic visibility scenario. It must be noted that a detailed tree survey of existing tree cover immediately adjacent the Proposed Development has not been undertaken, and that the ZTV has been generated using an indicative height of 12 m, therefore, in


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reality, individual trees and the make-up of tree coverage may have a greater or lesser effect on screening than demonstrated on the ZTV.

The ‘with screening’ theoretical visibility for OHL elements of the Proposed Development is wide spread within the central portion of the study area. Towards the outer margins of the study area, the ZTV coverage becomes more fragmented as visibility is lost beyond intervening landform and forest plantations. Areas where a high degree of theoretical visibility is found i.e. a high number of towers visible in any one view are typically concentrated within the central portion of the study area and where a higher, more open landscape character facilitates more expansive and extensive views.

Viewpoints

Nineteen viewpoints were discussed and agreed with The Highland Council and SNH: • 1. Thurso cemetery

• 2. Glengolly / B874

• 3. A9 / Geiselittle

• 4. B874 / Aimster

• 5. Halkirk / B874

• 6. A9 / Sordale

• 7. Hill of Olrig

• 8. Hoy

• 9. Castletown / B876

• 10 Lyth

• 11. Reaster

• 12. Mounthalie

• 13. Dunnet

• 14. Dunnet Head

• 15. Inkstack / NCN 1

• 16. A836 / Whitebridge

• 17. Castle of Mey

• 18. NCN 1 / Rigifa

• 19. Philips Mains

The locations of these are shown on Figure 6.5 together with the ‘With Screening’ ZTV overlaid. Information about the viewpoints is presented in Technical Appendix 6.2 which also contains a description of the existing visual amenity.

Future Baseline

With declining agricultural use there may be an increase in plantation forestry. However, it is likely that forest and woodland cover within the area will remain generally constant in the vicinity of the Proposed Development given the lack of suitable locations.


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The landscape and visual resource of the Caithness landscape and the study area is likely to change in the future as a result of the construction of those developments listed in Table 6.2. The effects of the Proposed Development in addition to these other developments are discussed in the cumulative assessment section of this chapter.

6.6 Potential Effects

The assessment is based on the tower schedule included within the s37 application and set out within Appendix 2.2. Sealing End Compounds (SECs) as described in Section 2.4 have also been assessed.

As noted within Chapter 2, it is possible that individual tower locations might alter following micro siting within the LOD (as shown on Figures 2.1 to 2.4). The following assessment does not assess different scenarios within the LOD. For the landscape resource, any such variations to the route would be unlikely to alter the conclusions of the assessment. For visual amenity, only those viewpoints in very close proximity to the LOD would be likely to be affected by any change to individual tower locations i.e. viewpoint 7 (Hoy) and viewpoint 11 (Reaster).

OHL, Landscape Resource

Potential OHL Construction Effects on the Landscape Resource

Landscape changes would commence with the introduction of materials, labour force, construction vehicles and plant, and the establishment of construction compounds and site accommodation into localised areas along the OHL section of the Proposed Development, where no such features or activity currently exist – i.e. between Weydale Farm South and east of Moss-side House. These changes would be of a temporary nature and would change their location and extent in relation to the progress of the construction works. Access development and other enabling works (forestry felling and establishment of site compounds) would occur over an estimated 7 month period. This would be followed by the installation of tower foundations, which would take approximately 13 months, and the installation of towers (approximately 9 months), conductor stringing (estimated 4 months), and OHL commissioning (approximately 8 months). (Phases 2 to 6 as described in Table 2.2). Temporary works would be removed and reinstatement work would be undertaken rendering the construction effects as temporary and reversible with an estimated total duration of 45 months.

The Proposed Development would result in direct temporary changes to the existing detailed landform immediately around tower locations during excavations for tower foundations, although these changes would be of a relatively minor nature. Any permanent changes to the detailed landform around tower locations would be of a minor nature and would not change or adversely affect the overall landform pattern of the study area.

The Proposed Development would involve vegetation clearance around tower locations, the upgrading of existing or establishment of new junction bellmouths and creation of access tracks, and road infrastructure (bridges, culverts etc.). The overall length and extent of these would be limited to locations around Weydale Farm South, South Weydale Cottages, north of Marl Moss, south of Duran, east of Hoy Farm Bungalow and Wester Olrig Cottages, south of Moss of Tain, and at Moss of Greenland.


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There would be permanent loss of small areas of agricultural land due to the requirement for new or upgraded accesses. The Proposed Development would also result in the direct temporary loss of small areas of agricultural land and moorland due to the establishment of construction compounds, lay-down areas and new sections of temporary access tracks, associated with the construction of the Proposed Development. These areas would be reinstated to their current condition on completion of the construction works, and would therefore have no overall impact on the land-use and landscape character of the study area.

The Proposed Development would require crossing of the existing 33 kV and 11 kV distribution network and where this is required, the distribution network would be undergrounded resulting in temporary disturbance due to excavations.

The Proposed Development would introduce activity associated with the construction of a new section of OHL into areas of landscape where such elements are currently not present or of limited occurrence. These operations would include temporary measures arising from construction works to protect road and water crossings (scaffolding).

Potential OHL Operational Effects on the Landscape Resource

The Proposed Development would introduce a new OHL into the study area, forming a large scale, man-made, linear feature comprising of relatively regularly spaced, large scale, vertical towers connected by overhead transmission cables, and SEC enclosures into a landscape where currently such features are of limited occurrence or not present.

The introduction of the Proposed Development would result in a direct and permanent change to the existing landscape resource.

There would be minor direct and permanent changes to the landform where the development and access tracks marry into the surrounding topography.

Direct permanent loss of agricultural land and moorland would result from the final placement of the individual towers, SECs and associated access tracks.

The Proposed Development would run through two Landscape Character Types - Mixed Agriculture and Settlement LCT, which occupies a moderate proportion of the study area (57.63% - discounting the area of sea), and Sweeping Moorland LCT, which occupies a smaller proportion of the study area (18.12% - discounting the area of sea). These areas would accrue direct effects.

Other LCTs which have theoretical visibility of the Proposed Development and would accrue indirect effects.

Duncansby Head SLA has been scoped out of the assessment as there is no theoretical visibility of the Proposed Development from that location.

Landscape Effects are described in Technical Appendix 6.2 and are summarised in Table 6.10.


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Table 6.10 Effects on the Landscape Resource - OHL

LCT/designation Construction Operation

Sweeping Moorland

Moderate adverse direct and moderate indirect and temporary


Flat Peatland Minor direct and temporary Minor direct and permanent

Open Intensive Farmland

Minor direct and temporary Minor direct and permanent

Mixed Agriculture and Settlement

Moderate adverse direct and moderate adverse indirect and temporary

Moderate adverse direct and moderate adverse indirect permanent

Small Farms and Crofts Minor direct and temporary Minor direct and permanent

High Cliffs and Sheltered Bays

No effect No effect

Long Beaches, Dunes and Links

Minor direct and temporary Minor direct and permanent

Harbour No effect No effect

Town No effect No effect

Dunnet Head SLA Minor adverse indirect and temporary

Minor adverse indirect and permanent

Castle of Mey G&DL Negligible Negligible

Underground Cable - Landscape Resource

Potential Underground Cable Construction Effects on the Landscape Resource

Landscape changes would commence with the introduction of materials, labour force, construction vehicles and plant, and the establishment of construction compounds and site accommodation into localised areas along the underground cable section of the Proposed Development, where no such features or activity currently exist – i.e. between Thurso South substation and Weydale Farm South and between east of Moss-side House and the proposed Gills Bay substation site. These changes would be of a temporary nature (anticipated as being of 4 months duration) and would change their location and extent in relation to the progress of the construction works.

The Proposed Development would result in direct temporary changes to the existing detailed landform along the cable trench during excavations, although these changes would be of a relatively minor nature. Any permanent changes to the detailed landform around the cable trench would be of a minor nature and would not change or adversely affect the overall landform pattern of the study area.

The Proposed Development would involve some forestry clearance south of the proposed Gills Bay substation, the upgrading of existing or establishment of new junction bellmouths and access tracks, road infrastructure (bridges, culverts etc.) infrastructure.


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The Proposed Development would introduce activity associated with the installation of new sections of underground cable into areas of landscape where such elements are currently not present or of limited occurrence. These operations would include temporary measures to protect road and water crossings (scaffolding) and all of the effects arising from construction works would be temporary, with the exception of the area of felled forestry.

Potential Underground Cable Operational Effects on the Landscape Resource

The only operational effects arising from the underground cable would be the loss of commercial forestry cover in the vicinity of Gills Bay substation. Construction effects are described in Technical Appendix 6.2 and are summarised in Table 6.11.

Table 6.11 Effects on the Landscape Resource – underground cable

LCT Construction Operation

Sweeping Moorland Minor adverse direct and minor indirect and temporary

No effect

Flat Peatland Negligible No effect

Open Intensive Farmland Negligible No effect


Minor adverse direct and minor indirect and temporary

No effect

Small Farms and Crofts Minor direct and temporary No effect

High Cliffs and Sheltered Bays No effect No effect

Long Beaches, Dunes and Links

Negligible No effect

Harbour No effect No effect

Town No effect No effect

Dunnet Head SLA No effect (beyond 5 km) No effect

Castle of Mey G&DL No effect (beyond 5 km) No effect

OHL - Visual Amenity, Viewpoints

Potential OHL Construction Effects on Visual Amenity

Construction operations would introduce man-made elements and activities into views, where currently such elements and activities do not exist.

People at some of the viewpoint locations will be affected by construction works. Road and rail users in the vicinity will also be affected.

Likely effects for each of the viewpoints are described Technical Appendix 6.3 and are summarised in Table 6.12.

Potential OHL Operational Effects on Visual Amenity

The Proposed Development would introduce large structures with associated access tracks, and SECs into views of a rural landscape with dispersed settlement and associated infrastructure including roads and wood pole mounted overhead lines and steel lattice towers in the western portion of the study area.


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The Proposed Development would occupy views currently characterised by coastal farmland, sweeping moorland and blocks of coniferous forestry. Built development is concentrated within areas of coastal farmland to the north of the study area and is typically residential and agricultural.

Examination of the ‘bare ground’ ZTV confirms that the OHL element of the Proposed Development is theoretically visible from approximately 64% of the land based part of the study area. The ‘with screening’ ZTV confirms that this percentage would reduce to just over 53% although it should be noted that some locations would not have views due to the localised presence of forestry, woodland, hedges and other screening elements not included within the ZTV.


OHL – Visual Amenity, Sequential Assessment

Likely effects for each of the viewpoints and sequential routes are described Technical Appendix 6.3 and are summarised in Table 6.12.


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Table 6.12: Summary of Potential Effects on Visual Amenity - OHL

No Viewpoint Location

Grid Ref. Approx. Height AOD

Approx. Bearing to OHL

Reason for Selection

Approx. Distance to OHL

Construction Effects (all adverse and temporary)

Operation Effects (all adverse and permanent)

1 Thurso cemetery 331503, 967092 24 m 135o Cemetery users, proxy for urban edge of Thurso

4.75 km Minor Minor

2 Glengolly / B874 310528, 965403 54 m 110o Local residents, road users

3.75 km Minor Minor

3 A9 / Geiselittle 312373, 965551 40 m 130o Road users, local residents

2.2 km Minor Minor

4 B874 / Aimster 311876, 963385 39 m 80o Road users, local residents

2.5 km Minor Minor

5 Halkirk / B874 314324, 960099 29 m 15o Local residents, road users

4 km Minor Minor

6 A9 / Sordale 314738, 962378 39 m 20o Road users, local residents

1.5 km Moderate Moderate

7 Hill of Olrig 317500, 965168 119 m 160o Walkers, visitors

1.75 km Severe Severe

8 Hoy 320974, 963847 42 m 40o Road users, local residents


9 Castletown / B876

320455, 967005 23 m 135o Local residents, road users

3 km Moderate Moderate


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10 Lyth 328151, 963397 44 m 320o Local residents, road users

3.2 km Negligible Negligible

11 Reaster 326016, 965361 47 m 310o Road users, local residents


12 Mounthalie 325693, 966764 72 m 140o Road users, local residents


13 Dunnet 321161, 971704 40 m 140o Local residents, road users


14 Dunnet Head 320531, 976491 127 m 150o Tourists, visitors


15 Inkstack / NCN 1 325946, 970336 56 m 180o Local residents, road users


16 A836 / Whitebridge

327028, 972431 19 m 190o Road users, local residents

2.2 km None None

17 Castle of Mey 328974, 973305 31 m 200o Garden and Designed Landscape, tourists, visitors, road users

1.9 km None None


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18 NCN 1 / Rigifa 330132, 972702 50 m 220o Road users, local residents

1.2 km None None

19 Philips Mains 329752, 971906 47 m 215o Residents 0.5 km None None

A9 Southbound Moderate Moderate

A9 Northbound Minor Minor

A836 Eastbound Minor Minor

A836 Westbound Moderate Moderate

A882 Northbound Severe Severe

B855 Southbound Moderate Moderate

B855 Northbound None None

B870 South/ Eastbound Negligible Negligible

B870 West/ Northbound Minor Minor


B874 Northbound Minor Minor

B876 Southbound Minor Minor

B876 Northbound Major Major

NCR1 Eastbound Moderate Moderate


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NCR1 Westbound Minor Minor

Rail – Thurso to Loch Watten Southbound Moderate Moderate

Rail – Thurso to Loch Watten Northbound Moderate Moderate

Rail – Scotscalder to Georgemass junction Northbound Major Major

Rail – Scotscalder to Georgemass junction Southbound None None


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Underground Cable - Visual Amenity

Potential Underground Cable Construction Effects on Visual Amenity

Construction operations would introduce man-made elements and activities into views, where currently such elements and activities do not exist.

People at some of the viewpoint locations close to the underground cable route would be affected by construction works. Road and rail users in the in close proximity will also be affected.


Effects arising as a result of construction operations associated with the underground cable have not been assessed in detail. There are likely to be temporary effects at locations on the A9 and B874 resulting from trench excavation and cable installation between Thurso substation and South Weydale and at locations on NCR1 resulting from construction works of the section of underground cable at Lochend. None of these are considered to be likely to be significant.

Table 6.13: Effects of the Proposed Development on Visual Amenity – underground cable

Viewpoint Construction Operations

1.Thurso cemetery Refer to Figure 6.6

Minor adverse temporary No effect

2.Glengolly / B874 Refer to Figure 6.7


3.A9 / Geiselittle Refer to Figure 6.8


4.B874 / Aimster Refer to Figure 6.9


5.Halkirk / B874 Refer to Figure 6.10


6.A9 / Sordale Refer to Figure 6.11


7.Hill of Olrig Refer to Figure 6.12


8.Hoy Refer to Figure 6.13


9.Castletown / B876 Refer to Figure 6.14


10.Lyth Refer to Figure 6.15



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Table 6.13: Effects of the Proposed Development on Visual Amenity – underground cable

Viewpoint Construction Operations

11. Reaster Refer to Figure 6.16


12.Mounthalie Refer to Figure 6.17


13.Dunnet Refer to Figure 6.18


14.Dunnet Head Refer to Figure 6.19


15.Inkstack / NCN 1 Refer to Figure 6.20


16.A836 / Whitebridge Refer to Figure 65.21

No effect No effect

17.Castle of Mey Refer to Figure 6.22

No effect No effect

18.NCN 1 / Rigifa Refer to Figure 6.23


19. Philips Mains Refer to Figure 6.24


Potential Underground Cable Operational Effects on Visual Amenity

As the cable would be below ground, there would be no visual effects arising from its presence.

6.7 Mitigation

Mitigation, and consideration of landscape design, has been an integral part of the overall design strategy for the Proposed Development and a positive, pro-active approach has been adopted at each stage of project design to incorporate mitigation and landscape design measures. The process is described and discussed further in Chapter 4: Route Selection and Alternatives.

Mitigation for landscape and visual effects has consisted of adherence, as far as possible to the Holford Rules as set out in Technical Appendix 4.2.

The assessments detailed in Technical Appendix 6.2 and 6.3 take into account all relevant mitigation measures to which the Applicant has given a firm commitment.


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Mitigation by Design

Mitigation by Design – OHL

The location and definition of the Proposed Development has been informed by various routing principles, which, amongst other things have sought to avoid and reduce impacts on landscape character and visual amenity where ever possible. Chapter 4 describes the route selection and alternatives considered and explains, where environmental considerations, including landscape and visual factors have influenced the process. The undergrounding sections of the Proposed Development offer significant design mitigation on landscape and visual effects for receptors at the western and eastern ends of the Proposed Development when compared to an OHL through these areas.

Mitigation by Design – Underground Cable

The underground cable itself provides effective mitigation to potential landscape and visual effects during the operational phase. Construction effects would be reduced due to the elimination of any tall machinery of the sort required for tower installation.

Mitigation during Construction – OHL

A CEMD/CEMP would be prepared defining the methodologies and management measures to be employed in the construction of the Proposed Development (Refer to Section 2.11 and Appendix 2.1). The CEMD/CEMP would include, amongst other information the following commitments to landscape and visual mitigation: • final positioning of access tracks would be selected to minimise loss of.

vegetation and construction activity would be contained within the defined LOD;

• any upgrading of existing access tracks, to allow construction access, would be in keeping with the character of existing tracks/footpaths e.g. materials and scale;

• temporary works associated with construction would be removed following completion and soils and vegetation would be re-established. Regrowth from the existing seed-bank would be encouraged in preference to active seeding of the reinstated soils. Reinstatement of access tracks would be completed in consultation with SNH;

• any boulders within the tower construction footprint would be carefully removed and set aside for subsequent repositioning during reinstatement operations;

• all trees and hedgerows within the vicinity of works would be adequately protected through the preparation of a Tree Protection Plan, including a Root Protection Zone (RPZ), following an arboriculturist's assessment (BS 5837:2012 Trees in Relation to Construction) unless consented for removal by The Highland Council. This may include barrier and ground protection and site monitoring;

• any requirement to remove trees or hedgerows to facilitate construction would be agreed with The Highland Council. Trees and hedgerows would be reinstated wherever possible on completion of construction; and

• tower installation would be undertaken in short sections with progressive restoration where possible.


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Mitigation during Construction – Underground Cable

These would conform to the measures listed above for tower installation with the additional requirement to excavate and progressively restore the underground cable corridor.

Mitigation during Operation

This section considers mitigation measures that would occur once the transmission line is constructed, for example medium to long-term maintenance and management of enhancement measures.

Mitigation during Operation – OHL

Any planting to mitigate for loss of commercial forestry would be maintained by the Applicant for at least 5 years, at which point it would become the responsibility of the landowner. Replacement planting would be undertaken, as necessary within this period to account for any failures.

Mitigation during Operation – Underground Cable

Any planting to mitigate for loss of commercial forestry for wayleaves would be maintained by the Applicant for at least 5 years, at which point it would become the responsibility of the landowner. Replacement planting would be undertaken, as necessary within this period to account for any failures. No further mitigation measures for landscape and visual impacts during operation of the underground cable is required as these sections will not have visual impacts.

6.8 Assessment of Residual Effects

The assessment detailed in Technical Appendices 6.1 – 6.4 take into account all mitigation measures incorporated into the Proposed Development.

6.9 Cumulative Effects

Cumulative landscape and visual effects are considered in Table 6.15. The assessment is based on information available on The Highland Council planning website. For some pre-application proposals, there is no ZTV available. Only those viewpoints assessed as accruing significant adverse effect as a result of the Proposed Development (as summarised in Table 6.15) have been considered.


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Table 6.14: Cumulative Assessment

Consented

Stroupster wind farm

Stroupster windfarm is a proposal for 11 turbines with a blade tip height of 113 m. This development would be located some 8km to the east of the Proposed Development. It would be located in an area of coniferous woodland plantation surrounded by LCT Flat Peatland. Indirect cumulative effects would occur for this LCT and for Sweeping Moorland and Mixed Agriculture and Settlement. There is theoretical visibility of this development from viewpoints 7 (Hill of Olrig), 8 (Hoy), 9 (Castletown), 11 (Reaster) and 14 (Dunnet Head) and cumulative effects can be anticipated to occur for people at these locations and for vehicle travellers on routes east of the A9.

Lochend wind farm

Lochend wind farm is a proposal for 4 turbines with a blade tip height of 100 m. It would be located approximately 3.5 km to the north east of the easternmost terminal tower in an area of Sweeping Moorland which would accrue direct and indirect cumulative effects. Other LCTs would accrue indirect cumulative effects. There is theoretical visibility of this development from viewpoints 7 (Hill of Olrig), 9 (Castletown), 11 (Reaster) and 14 (Dunnet Head) and cumulative effects can be anticipated to occur for people at these locations and road users in the vicinity of the two developments.

Thurso substation

Cumulative landscape and visual effects can be anticipated to occur in the vicinity of the substation site and the western extremity of the Proposed Development with direct effects occurring for the LCT Mixed Agriculture and Settlement and other indirect effects for other LCTs. Cumulative visual effects can be anticipated for those locations assessed as accruing significant adverse effects from the OHL, although the levels of effect are unlikely to be greater than for the OHL alone – with the exception of the A9 southbound and the B874 southbound.

Dounreay – Mybster OHL

Cumulative effects can be anticipated in and around those areas where the two proposals will be in relatively close proximity – i.e. between Geiselittle and Sordale with these effects diminishing as the proposals diverge. Those areas and viewpoints within around 10km of the A9 are likely to accrue cumulative visual effects.

Murza wind turbine

This proposal is for a single turbine 19.28 m to blade tip. It will be located north of the B876 east of Bower. The ZTV extends to 15 km and indicates a concentration of theoretical visibility within 5 km with fragmented visibility at greater distances. It will be located in an area of Mixed Agriculture and Settlement. There would be localised direct and indirect cumulative effects on this LCT. There is theoretical visibility from viewpoints 7 (Hill of Olrig) some 7.65 km distant. The turbine would be seen beyond the OHL. Cumulative effects would be no greater than those for the OHL in isolation.


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Meygen Tidal Cumulative landscape and visual effects are not anticipated as a result of the addition of the Proposed Development to this offshore tidal project.

Undetermined

Cnoc Morail wind farm

This wind farm proposal is for 8 turbines 110 m to blade tip. It would be located around 10 km to the south of the proposed OHL and would be situated in an area of LCT Mixed Agriculture and Settlement on which there would be both direct and indirect cumulative effects. There would also be indirect effects for other LCTs where the ZTVs of both developments overlap. The ZTV for this proposal is very widespread over the 35 km study area. There is theoretical visibility from viewpoints 7 (Hill of Olrig) and 9 (Castletown) which accrue significant effects from the OHL and cumulative effects can be anticipated for these locations and for many of the roads in the vicinity of both proposals.

Pre – Application

Buckies Farm wind farm

This proposal is for a linear 5 turbine array with turbine tip heights of 67m. It would be situated some 4km to the west of the western end of the OHL. The ZTV will undoubtedly overlap with that of the OHL and direct cumulative effects can be anticipated for LCT Mixed Agriculture and Settlement with other LCTs experiencing indirect effects. Most of the 19 viewpoints assessed are likely to have views of this wind farm and those assessed as accruing significant effects from the OHL would be likely to experience cumulative effects although, for VP 6 the proposed windfarm would be the more prominent feature in the view although the viewer would not see the two developments simultaneously. Cumulative effects would also be experienced by people travelling on the A9.

Cogle Moss wind farm

This proposal comprises 12 turbines of 100 m to blade tip. It would be located 5 km to the south of the proposed OHL in an area of Sweeping Moorland which would accrue direct and indirect cumulative effects. Other LCTs would accrue indirect cumulative effects. The ZTV contained in the Scoping Report indicates quite widespread theoretical visibility over the 30 km study area. The ZTV indicates theoretical visibility for viewpoints 7 (Hill of Olrig), 9 (Castletown) and 14 (Dunnet Head) which accrue significant effects from the OHL and cumulative effects can be anticipated for these locations and for many of the roads in the vicinity of both proposals.

Coghill/ Tofts of Tain wind farm This proposal is for three turbines 100m in height to blade tip. They would be located in an area of LCT Sweeping Moorland very close the eastern end of the OHL section. There would be direct and indirect cumulative effects on this LCT and indirect effects on other LCTs, particularly Mixed Agriculture and Settlement. There is no ZTV available for this project but it can be assumed that, given the location close


LT000022 6-49 Chapter 6:


Table 6.14: Cumulative Assessment to the proposed OHL and the height of the turbines that cumulative visual effects will occur for several static viewpoints and for routes in the study area.

Earls Cairn wind farm

This wind farm proposal is for 13 turbines with a blade tip height of 125 m. It would be located some 5 km east of Dunnet and approximately 5 km to the north east of the easternmost terminal tower. It would lie in an area of LCT Mixed Agriculture and Settlement which would accrue direct and indirect cumulative effects. Other LCTs may accrue indirect cumulative effects. There is no ZTV in the Scoping Report but given the location of this wind farm proposal, there are likely to be cumulative visual effects for some of the viewpoints in the east of the Proposed Development’s study area.

Gills Bay substation As the 7 km of the Proposed Development closest to the Gills Bay substation will be underground cable, it is considered that, while construction cumulative effects may occur, significant operational cumulative effects will not result.

Seater Farm Bower wind farm

Four turbines with a maximum blade tip height of 80m would be located on North Watten Moss some 5 km to the south of the OHL. There is considerable overlap between the ZTV in the scoping report for this development and that of the OHL. Direct and indirect cumulative effects can be anticipated for LCTs Mixed Agriculture and Settlement and Sweeping Moorland with indirect effects occurring for other LCTs. Many of the 19 viewpoint would have views of this development and the six assessed as accruing significant effects as a result of the OHL would experience cumulative effects. People travelling on the A9, B876 and B874 would experience cumulative sequential effects.

Stemster Hill wind farm

This proposal is for 4 turbines with a maximum blade tip height of 92.5 m. It would be located within 1 km of the OHL and cumulative direct effects can be anticipated for LCT Mixed Agriculture and Settlement and indirect effects for other LCTs. Due to the scale of the proposed turbines, the effects of the wind farm are likely to be far greater than for the OHL. Similarly, the wind turbines are likely to result in greater effects for static and moving viewers than would result from the OHL.

Tresdale wind farm

This proposal is for 3 turbines with a blade tip height of 99.5 m. It would be located some 10 km to the north-east of the eastern terminal tower in an area of LCT Sweeping Moorland which would accrue direct and indirect cumulative effects. Other LCTs would experience indirect cumulative effects. There is theoretical visibility of this development from viewpoints 7 (Hill of Olrig), 11 (Reaster) and 14 (Dunnet Head) and cumulative effects can be anticipated to occur for people at these locations and road users in the vicinity of the two developments.


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West and North West of Northfield wind farm

This proposal is for two turbines of 74 m to blade tip situated to the north west of Halkirk, some 4k m to the south west of the western SEC, in an area of LCT Mixed Agriculture and Settlement which would accrue direct and indirect cumulative effects. Other LCTs may accrue indirect cumulative effects. There is no ZTV in the Scoping Report but given the location of these wind turbines, there are likely to be cumulative visual effects for some of the viewpoints in the west of the study area for the Proposed Development.


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6.10 Summary of OHL Significant Effects

Significant effects are limited to two LCTs which are well represented in the study area and in the Caithness landscape generally. The remaining seven LCTs which are far less well represented in the study area would not experience significant effects.

In introducing a development of this length and height into a largely open landscape it is inevitable that significant direct and indirect effects would occur for those LCTs through which the Proposed Development would pass. By undergrounding 7 km of the route, these effects have been reduced for areas, particularly in the eastern portion of the study area.

There would be no significant effects for the Dunnet Head SLA or for the Castle of Mey Garden and Designed Landscape.

Table 6.15 summarise the potential significant residual landscape effects.

Table 6.15: Significant Operational Effects on the Landscape Resource - OHL

LCT/designation Construction Operation

Sweeping Moorland




Moderate adverse direct and moderate adverse indirect and temporary

Moderate adverse direct and moderate adverse indirect permanent

By undergrounding the eastern section of the Proposed Development, the levels of effect for three viewpoints (12. Mounthalie, 15. Inkstack and 19. Philips Mains) are predicted to be negligible, minor and none respectively. Predicted effects for a further four viewpoints (10. Lyth, 13. Dunnet, 16. A836 Whitebridge and 18. Rifigia) would also be minor, minor, none and none respectively.

Significant visual effects for static locations are limited to seven of the nineteen viewpoints assessed.

Severe effects are anticipated for one location (Hill of Olrig) which lies approximately 1.75 km from the Proposed Development and will overlook, from an elevated location, the entire length of the OHL element of the Proposed Development.

Moderate effects are anticipated for viewpoints which lie within 3 km and for one viewpoint (14 Dunnet Head) which although almost 10 km distant is in an elevated location with views over the entire length of OHL element of the Proposed Development.

Table 6.16 lists the significant visual effects.


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Table 6.16: Significant Effects of the OHL on Visual Amenity

No Viewpoint Location Construction Effects (all adverse and temporary)


6 A9 / Sordale Moderate Moderate

7 Hill of Olrig Severe Severe

8 Hoy Moderate Moderate

9 Castletown / B876 Moderate Moderate

11 Reaster Moderate Moderate

14 Dunnet Head Moderate Moderate

A9 Southbound Moderate Moderate

A836 Westbound Moderate Moderate

A882 Northbound Severe Severe



B876 Northbound Major Major

NCR1 Eastbound Moderate Moderate

Rail – Thurso to Loch Watten Southbound

Moderate Moderate

Rail – Thurso to Loch Watten Northbound

Moderate Moderate

Rail – Scotscalder to Georgemass junction Northbound

Major Major

6.11 Summary of Underground Cable Significant Effects

There are no significant landscape or visual effects predicted as arising from the underground cable.


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7 ECOLOGY

7.1 Introduction

7.1.1 This chapter considers the potential impacts on ecological receptors from the construction and operation of the Proposed Development. The specific objectives of the assessment are outlined below: • to identify designated sites and habitats in the vicinity of the Proposed

Development which are considered to be of conservation or ecological value;

• to investigate the presence/possible presence of protected species and other species of particular conservation value;

• to describe the likely potential impacts as a result of the Proposed Development both during construction and once completed;

• to describe the pre-construction mitigation measures that have been committed to in order to avoid or reduce impacts;

• to describe the restoration measures and opportunities for ecological enhancement that would be implemented following completion of the works; and

• to assess the significance of residual impacts that are likely to remain following implementation of mitigation and restoration measures.

7.1.2 This chapter and the impact assessment described within have been prepared by Danny Oliver ACIEEM and Adam Fitchet MCIEEM of Ramboll Environ UK Limited (Ramboll Environ). All field surveys were completed by suitably qualified Ramboll Environ ecologists. Full details of the field surveys, including surveyors, are given in Technical Appendix 7.1.

7.2 Legislation and Policy Context International Legislation and Policy

EC Directive on the Conservation of Natural Habitats and Wild Flora and Fauna, 92/43/EEC

7.2.1 The EC Habitats Directive1 promotes the maintenance of biodiversity in Europe. The Directive provides for the creation of a network of protected areas across the continent, designated by member states as Special Areas of Conservation (SACs). Together with Special Protection Areas (SPAs) designated under the EC Birds Directive (see Chapter 8: Ornithology), SACs form a network of pan-European protected areas known as Natura 2000. The annexes to the Directive list habitats and species of importance in a Europe-wide context.

The Ramsar Convention on Wetlands

7.2.2 The Convention on Wetlands2 is an intergovernmental treaty signed in Ramsar, Iran in 1971, which details the commitments of its member countries to maintain the ecological character of their Wetlands of International Importance and to plan for the sustainable use of all of the wetlands in their territories.

1 http://ec.europa.eu/environment/nature/legislation/habitatsdirective/index_en.htm 2 http://www.ramsar.org/cda/en/ramsar-about-mission/main/ramsar/1-36-53_4000_0__


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Chapter 7: Ecology 7-2 LT000022

National Legislation and Policy

The Conservation (Natural Habitats etc.) Regulations 1994 (As Amended)

7.2.3 These Regulations3 (hereafter referred to as 'the Conservation Regulations') transpose Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora (EC Habitats Directive) into national law. The Regulations provide for the designation and protection of so called 'European' sites, the protection of European Protected Species (EPS), and the adaptation of planning and other controls for the protection of European sites.

The Wildlife and Countryside Act 1981 (As Amended)

7.2.4 The Wildlife and Countryside Act (WCA) 19814 (and its subsequent amendments) is the principal mechanism for the legislative protection of wildlife in Great Britain. The Act establishes a statutory framework for the protection of wildlife and also serves to implement the various European Directives. The Act provides for the designation of Sites of Special Scientific Interest (SSSI), which are selected as the best national examples of habitat types, sites with notable species and sites of geological importance. The Act provides additional protection of certain animals including, otter Lutra lutra, water vole Arvicola amphibius, and pine marten Martes martes. Schedule 8 of the Act details protection for plants and fungi.

Nature Conservation (Scotland) Act 2004

7.2.5 This Act5 places duties on public bodies in relation to the conservation of biodiversity, increases protection for SSSIs, amends legislation on Nature Conservation Orders, provides for Land Management Orders for SSSIs and associated land, and strengthens wildlife enforcement legislation. The Act places a duty on every public body to further the conservation of biodiversity consistent with the proper exercise of their functions.

Wildlife and Natural Environment Scotland Act 2011

7.2.6 This Act6 was introduced to make the law on wildlife and the natural environment more efficient, effective and proportionate. The main purposes of the Act are: to modernise deer management legislation and game law; introduce new rules on snaring; ensure badger licensing legislation is consistent with that of other species; control, contain and eradicate invasive non-native species; improve the administration of species licensing; abolish the Areas of Special Protection designation; increase flexibility in how muirburn is carried out; and improve SSSI legislation.

The Protection of Badgers Act 1992

7.2.7 This Act7 consolidates legislation specific to badgers Meles meles. It makes it an offence to wilfully take, kill, injure or ill-treat a badger; to obstruct, destroy or damage in any part, a badger's sett, or to disturb badgers within a sett.

3 http://www.legislation.gov.uk/uksi/1994/2716/contents/made 4 http://www.legislation.gov.uk/ukpga/1981/69 5 http://www.legislation.gov.uk/asp/2004/6/contents 6 http://www.legislation.gov.uk/asp/2011/6/enacted 7 http://www.legislation.gov.uk/ukpga/1992/51/contents


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7.2.8 The Scottish Government published its Scottish Planning Policy (SPP)8 document in June 2014. With regards to ecology it highlights a number of key Policy Principles that the planning system should upkeep; these being to: • facilitate positive change while maintaining and enhancing distinctive

landscape character;

• conserve and enhance protected sites and species, taking account of the need to maintain healthy ecosystems and work with the natural processes which provide important services to communities;

• promote protection and improvement of the water environment, including rivers, lochs, estuaries, wetlands, coastal waters and groundwater, in a sustainable and co-ordinated way;

• promote protection and improvement of the water environment, including rivers, lochs, estuaries, wetlands, coastal waters and groundwater, in a sustainable and co-ordinated way;

• seek to protect soils from damage such as erosion or compaction;

• protect and enhance ancient semi-natural woodland as an important and irreplaceable resource, together with other native or long-established woods, hedgerows and individual trees with high nature conservation or landscape value;

• seek benefits for biodiversity from new development where possible, including the restoration of degraded habitats and the avoidance of further fragmentation or isolation of habitats; and

• support opportunities for enjoying and learning about the natural environment.

7.2.9 SPP is concerned with the consolidation of a number of separate policies on issues such as sustainable development, community engagement and the natural environment in to one concise policy document. Essentially, there is little change to previous policy and SPP makes clear that where possible, planning authorities should seek benefits for species and habitats from new development including the restoration of degraded habitats. It goes on to state that statutory natural heritage designations are important considerations where they are affected by a development proposal and the need for Appropriate Assessment of proposals potentially impacting SACs and SPAs is made clear. SPP clarifies that the level of protection given to local designations through the development plan should not be as high as the level of protection given to international or national designations.

UK Biodiversity Action Plan (UK BAP)

7.2.10 The UK BAP9, produced in 1994 by the UK Government, is a national strategy for the conservation of biodiversity. It is the UK Government's response to the Convention on Biological Diversity (CBD) signed in 1992. The Convention called for the development and enforcement of national strategies and associated action plans to identify, conserve and protect existing biological diversity, and to enhance it wherever possible. Action plans for the most threatened species and habitats have been developed to aid recovery, and achieve the significant reduction in biodiversity loss called for by the CBD.

8 http://www.scotland.gov.uk/Publications/2014/06/5823 9 http://jncc.defra.gov.uk/default.aspx?page=5155


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Regional and Local Policy

Highland Biodiversity Action Plan 2010-2013

7.2.11 The second edition of the Highland Biodiversity Action Plan (BAP)10 was published in 2010 by The Highland Council on behalf of the Highland Biodiversity Partnership which oversees progress and addresses some of the more strategic issues facing Highlands' nature and wildlife. The first Highland BAP was produced in 2006; the second edition updates the Highland BAP and reprioritises work for the Partnership. The plan details the UKBAP species found in the Highland region such as pine marten, polecat Mustela putorius, soprano pipistrelle Pipistrellus pygmaeus, brown long-eared bat Plecotus auritus, adder Vipera berus and common lizard Zootoca vivipara.

7.2.12 The Highland Biodiversity Action Plan 2015-2020 is currently in its draft stage. It has been prepared by the Highland Environment Forum (HEF) and was due for launch in March 2015. It summarises the background and context of the plan as well as providing an update of the progress made since the biodiversity action plan process began in 2002. It also proposes new project ideas that could be undertaken to improve the biodiversity of Highland.

Caithness Biodiversity Action Plan

7.2.13 The Caithness Biodiversity Action Plan11 was published in February 2003 and details the six key habitat groups within the Caithness area, the key species, both faunal and floral found within them and the measures that can be adopted to enhance them. Key species listed in the CBAP are: water vole, brown hare Lepus europaeus, otter and common pipistrelle Pipistrellus pipistrellus.

7.3 Issues Identified during Consultation

7.3.1 Table 7.1 below summarises the issues identified during the consultation process that are of ecological relevance.

Table 7.1: Issues Identified during Consultation


SEPA The ES should demonstrate how the layout and design of the proposal, including any associated borrow pits, hard standing and roads, avoid impact on wetlands and peatlands, with NVC survey of wetlands completed in order to identify any groundwater dependent terrestrial ecosystems.

Details of the NVC Survey are provided in paragraphs 7.5.37 to 7.5.50. An assessment of impacts on habitats is provided in paragraphs 7.6.3 and 7.6.9 – 7.6.10. Descriptions of how impacts on wetlands and peatlands would be avoided are given in Chapter 4: Route Selection and Alternatives and in paragraphs 7.7.5 and 7.7.9.

10 http://www.highlandbiodiversity.com/pdf/Highland_Biodiversity_Action_Plan_2010-2013.pdf 11 http://www.highlandbiodiversity.com/htm/counties/caithness/caithness.pdf


LT000022 7-5 Chapter 7:

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SNH SNH recommend that all mammal surveys are completed within 18 months of the application submission.

Protected Species surveys were carried out in August and September 2011, September 2012 and October 2013. This data is thought to be sufficient as discussed in paragraph 7.4.8.

SNH The following non-ornithological protected sites should be included in the EIA: Loch of Durran SSSI; River Thurso SAC; and Loch Heilen SSSI.

Paragraphs 7.6.2 and 7.6.7 – 7.5.8 give an assessment of the potential impacts on the River Thurso SAC and SSSI, Loch of Durran and Loch Heilen.

Bower Community Council

Concern for wildlife. This chapter addresses how impacts of the Proposed Development on wildlife would be reduced and mitigated for. See also Chapter 8: Ornithology.

Marine Scotland

Concern for fish populations in the study area. Baseline conditions are described in Section 7.5.58. Impacts related to designated site and habitat destruction/degradation, described in paragraphs 7.6.3, and 7.6.9 – 7.6.10.


Study Area

7.4.1 A field study area equivalent to an approximately two km wide corridor either side of the proposed alignment was established for the purposes of refining the proposed alignment. A wider desk study area was established three km either side of the field study area. Their relationship is shown in figure 7.1.

7.4.2 Where the proposed alignment has been defined outside of the original field study area addition surveys have been undertaken to survey these additional areas.

Desk Study

7.4.3 A desk study was carried out in March 2011 and updated in May 2015. On both occasions the following sources were considered: • SNHi12;

• NBN Gateway13;

• Durran Mains wind farm Environmental Statement14; and

12 http://www.snh.gov.uk/publications-data-and-research/snhi-information-service/ 13 https://data.nbn.org.uk/ 14 Highland Council Planning Application 08/00386/FULCA - Erection of 13 no. wind turbines with height of 55m to the hub,

control building, anemometer mast, temporary construction compound and access tracks | Land At Mains Of Durran Castletown Thurso Highland


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• Lochend wind farm Environmental Statement15.

Field Surveys

7.4.4 Field surveys considered the following:

PHASE 1 HABITAT SURVEY

7.4.5 An extended Phase 1 habitat survey was carried out between August 2011 and September 2011 following the prescribed methodology16 across the field study area. This survey provided an overview of the habitat types characterised in the immediate vicinity of the Proposed Development. The field study area was resurveyed in both September 2012 and October 2013 and results were noted to be consistent.

NATIONAL VEGETATION CLASSIFICATION SURVEY

7.4.6 A targeted National Vegetation Classification (NVC) survey was undertaken in October 2013; focussing on habitats identified during the Phase 1 habitat surveys as possible Groundwater Dependent Terrestrial Ecosystems (GWDTE). This provided a more detailed representation of the plant species assemblages present to allow the ecological importance of these communities to be assessed. The surveys followed the guidance outlined in Rodwell (2006)17.

PROTECTED SPECIES

7.4.7 Protected species surveys were undertaken at the same time as Phase 1 habitat surveys in August and September 2011, September 2012 and October 2013. These surveys sought field evidence of protected mammal species; badger Meles meles, otter Lutra lutra, pine marten Martes martes, red squirrel Sciurus vulgaris, Scottish wildcat Felis sylvestris and water vole Arvicola amphibius. The objective was to confirm their presence within the field study area and to locate possible territories. Potential bat roosting locations such as mature trees and buildings were also identified.

7.4.8 In its scoping response, SNH requested that survey data was completed within 18 months of the date of submission. Although survey data presented herein is older than 18 months, surveyors have been present on site for ornithological surveys up until April 2015 and no new signs have been recorded. Mammals are not thought to be adversely affected by the Proposed Development.


Overview

7.4.9 The assessment presented here was completed according to the CIEEM Guidelines (2006)18 and comprised the following steps: • the baseline was defined, i.e. an assessment of the field study area in its

current status, condition and ecological valuation was made;

15 Highland Council Planning Application - 13/02682/FUL | Erection of 4 no 2300kw wind turbines with a height to tip of 99.5m,

height to hub of 64m, rotor diameter of 71m and associated infrastructure - | Land 978M SE Of 2 Lochend Holding Barrock 16 JNCC (2010) Handbook for Phase 1 habitat survey, JNCC Peterborough 17 Rodwell, J.S. (2006) National Vegetation Classification: Users’ Handbook, JNCC Peterborough 18 CIEEM (2006) Guidelines for Ecological Impact Assessment in the United Kingdom. Accessed at

http://www.cieem.net/data/files/Resource_Library/Technical_Guidance_Series/EcIA_Guidelines/TGSEcIA-EcIA_Guidelines-Terestrial_Freshwater_Coastal.pdf


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• the potential impacts from the Proposed Development (direct and indirect) and sources of impact on protected faunal receptors were defined and quantified, where possible, in terms of magnitude, direction, extent, reversibility, likelihood and duration. Impacts resulting from the Proposed Development were considered for both the construction and operational stages;

• consideration was given to the identification of mitigation and enhancement measures to be integrated into the Proposed Development; and

• the nature and significance of residual effects remaining after the mitigation and enhancement measures were applied was assessed and, where considered appropriate, suitable additional mitigation measures described.

7.4.10 For the purpose of this assessment, the ecological receptors that were considered include: • designated sites (River Thurso SAC and SSSI, Loch Durran SSSI and Loch

Heilen SSSI);

• habitats (GWDTE and bog habitats); and

• species (otter, water vole and fish species).

7.4.11 These receptors were surveyed for within and surrounding the desk and field study areas. The method of assessing the ecological importance of the receptors is described in paragraph 7.4.13.

7.4.12 For the purpose of the assessment presented here mitigation refers to measures that would be incorporated into the Proposed Development to avoid, reduce, repair, reinstate, restore, 'rescue' and/or off-set adverse impacts.

Receptor Evaluation

7.4.13 The receptors identified within the study area were assigned ecological values using the standard CIEEM. The following frame of reference has been used: • International importance;

• National (UK) importance;

• Regional importance;

• County (metropolitan) importance;

• District (borough) importance;

• Local (parish) importance;

• Site Level importance (important within the Site and immediate environs); and

• Negligible importance.

7.4.14 Table 7.2 provides an indicative framework for the valuation of nature conservation features at different geographical scales and to different populations of species.


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Table 7.2: Geographic Conservation Values

Value Examples

International Internationally designated sites including Special Areas of Conservation (SAC), Ramsar site, Biogenetic Reserve, World Heritage Site, Biosphere Reserve, candidate SACs and potential Ramsar sites; discrete areas which meet the published selection criteria for international designation but which are not themselves designated as such; or a viable area of a habitat type listed in Annex I of the Habitats Directive, or smaller areas which are essential to maintain the viability of a larger whole. Resident or regularly occurring populations of species which may be considered at an International / European level1, the loss of which would adversely affect the conservation status or distribution of the species at an International / European level.

National Nationally designated sites including Sites of Special Scientific Interest (SSSI), National Nature Reserves (NNR), Marine Nature Reserve; discrete areas which meet the published selection criteria for national designation (e.g. SSSI selection guidelines) but which are not designated as such; or areas of a key habitat type identified in the UK Biodiversity Action Plan. Resident or regularly occurring populations of species which may be considered at the UK or National level2, the loss of which would adversely affect the conservation status or distribution of the species across Britain or the Country.

Regional Areas of a key habitat type identified in the Regional BAP such as the Highland BAP; viable areas of key habitat identified as being of Regional value in the appropriate Natural Heritage Zone (NHZ); or smaller areas of such habitat which are essential to maintain the viability of a larger whole. Resident or regularly occurring populations of species which may be considered at the Regional level, the loss of which would adversely affect the conservation status or distribution of the species across the Region.

County Designated sites at the county level including Sites of Nature Conservation Importance, County Wildlife Sites, Tree Preservation Orders; or discrete areas which meet the published selection criteria for county designation but which are not designated as such. Resident or regularly occurring populations of species which may be considered at the County level, the loss of which would adversely affect the conservation status or distribution of the species across the County.

District Designated sites at the local level including Local Nature Reserves (LNRs); or areas of habitat identified in a sub-county (district / borough) BAP. Resident or regularly occurring populations of species which may be considered at the District level, the loss of which would adversely affect the conservation status or distribution of the species across the District.

Local Features of local value include areas of habitat or populations / communities of species considered to appreciably enrich the habitat resource within the local context, for example, species-rich hedgerows.

Site Areas of habitat considered to appreciably enrich the habitat resource within the Site. Includes viable populations of species which are of importance within the Site.

Negligible Areas of heavily urbanised or intensively managed land with negligible value to wildlife.


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Value Examples

Notes: 1: - Species protected at a European level means: bird species listed within the Birds Directive or habitats, animal / plant species listed within the Habitats Directive. 2: - Species protected or which may be considered a the UK or National level means: birds, other animals and plants listed within Wildlife and Countryside Act 1981 (as amended) Schedules 1, 5 and 8 respectively; and / or listed for their principal importance for biodiversity in accordance with the Nature Conservation (Scotland) Act 2004 Section 2(4); species listed within the UKBAP or UK Red Data Books.

7.4.15 The sensitivity of an ecological receptor is defined as its susceptibility to being affected by an impact. For example otters are known to be particularly prone to disturbance from noise and light sources and so would be characterised as having a higher sensitivity than another species that is more tolerant of the same disturbance.

7.4.16 Receptors are considered to be of high, moderate or low sensitivity. This is judged by the ecologists undertaking the assessment using their judgement and experience. Sensitivity and value are independent of each other.

Impact Characterisation

7.4.17 The parameters set out in Table 7.3 have been used to characterise the impacts on each feature.

Table 7.3: Impact Characterisation

Parameter Description

Direction Impacts are either adverse (negative) or beneficial (positive).

Magnitude The size or amount of an impact, determined on a quantitative basis where possible, e.g. “partial” or “total” loss of an area of habitat or number of individuals affected. Where exact amounts are unquantifiable, this is defined simply as major, moderate or minor.

Extent The area over which an impact occurs.

Duration The time for which the impact is expected to last prior to recovery of the receptor or replacement of the receptor by similar resource (in terms of quality and / or quantity). This is expressed as follows: • Short-term = < 2 years. • Medium-term = > 2 to < 10 years. • Long-term = > 10 years.

Reversibility Irreversible impacts: permanent changes from which recovery is not possible within a reasonable time scale or for which there is no reasonable chance of action being taken to reverse it. Reversible impact: temporary changes in which spontaneous recovery is possible or for which effective mitigation (avoidance / cancellation / reduction of effect) or compensation (offset / recompense / offer benefit) is possible.


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Likelihood of Impact

The likelihood of an impact occurring. The following convention, adapted from the Intergovernmental Panel on Climate Change (IPCC),19 is adopted: • Virtually certain > 99% probability of occurrence • Extremely likely 96-99% • Very likely 91-95% • Likely 67-90% • More likely than not 51-66% • Possible 34-50% • Unlikely 11-33% • Very unlikely 6-10% • Extremely unlikely < 5%

Values are assigned using professional judgement, no statistical analysis is undertaken.


7.4.18 In this assessment an ecologically significant impact is defined in accordance with CIEEM (2006), as resulting from "an impact (positive or negative) on the integrity of a defined site or ecosystem and / or the conservation status of habitats or species within a defined geographical area." The determination of ecological significance is based on professional judgement. In addition, the value of the receptor defines the geographical terms of reference at which a predicted impact may result in a significant impact. Where an impact of at least moderate magnitude and a likelihood of occurrence of 'possible' (34-50%) or greater is identified on a receptor of greater than county level value, this is considered to result in an ecologically significant impact.

7.4.19 If an ecologically significant impact is identified this is also considered to be a significant effect in EIA terms.

7.4.20 For clarity, it is noted that some potential impacts are not considered significant in EIA terms. Where such effects are identified no specific mitigation is required, however good practice would be to control these effects as far as practicable.

7.5 Baseline Conditions Current Baseline

7.5.1 The full route and LOD of the Proposed Development is shown on Figures 7.3a-d and described in detail in Chapter 2: Description of the Development.

Future Baseline

7.5.2 The future baseline is unlikely to be different to the current one. Much of the land is modified by human activity and so any successional changes would be prevented from occurring by the combination of grazing and land management.

19 http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch1s1-6.html


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7.5.3 Ongoing climate change is resulting in higher yearly temperatures and altering the climatic conditions within the field study area. The yearly effects of this a small however and are unlikely to result in significant changes to the current baseline within the timescale of the Proposed Development.

7.5.4 There have been a high number of wind farm applications in the Caithness area. If any of these were accepted and were within the field study area then the habitats present would likely remain constant due to grazing activities.

7.5.5 There is however the possibility of increased plantation forestry in the area. Within an Orkney and Caithness context, SNH has spoken of the usefulness of commercial forestry in addressing climate change20. Although there are few obviously suitable locations for additional forestry within the study area it should be noted that in the event of further conifer planting a resultant loss of biodiversity within the future baseline could occur.

Designated Sites

7.5.6 The Proposed Development passes through, or close to, the following internationally and nationally designated sites (Figure 7.2).

River Thurso SAC, SSSI

7.5.7 The River Thurso SAC was designated in 2005 for supporting a population representing greater than 2% of the UK population of Atlantic salmon Salmo salar21. It also supports a high proportion of multi sea-winter salmon as well as a notable population of otters, though neither of these are qualifying species for the SAC.

7.5.8 The River Thurso was also notified as a SSSI in 1989, for the nationally important flood-plain fen habitat and flowering plants that grow along its banks and margins. Figure 7.2 shows that the two designations cover slightly different areas, with the SAC extending further upstream than the SSSI.

7.5.9 Both of these designations are about 500 metres from the LOD for the Proposed Development which also crosses tributaries of the main River Thurso constituting a potential impact pathway to this receptor.

Loch of Durran SSSI

7.5.10 Loch of Durran SSSI was notified in 1984 for its combination of vascular plant assemblage and wetland transitional grassland. Included in the plant assemblage are two rare species of small-reed, the narrow small-reed Calamagrostis stricta and the Scottish small-reed Calamagrostis scotica. The LOD of the Proposed Development passes 800 metres to the south-east of the SSSI and crosses drainage ditches that flow into the SSSI. This constitutes a potential impact pathway to this receptor.

Loch Heilen SSSI

7.5.11 Loch Heilen has been designated as a SSSI, SPA and Ramsar site as a result of its breeding waterfowl, (see Chapter 9: Ornithology), however it has also been

20 http://www.snh.gov.uk/docs/A306318.pdf 21 http://jncc.defra.gov.uk/ProtectedSites/SACselection/n2kforms/UK0030264.pdf


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notified as a SSSI as an important mesotrophic loch. The LOD for the Proposed Development passes 450 metres from the eastern edge of the SSSI.

7.5.12 The underground cable LOD passes within 400 metres of the Loch Heilen SSSI and crosses tributaries of the SSSI. This constitutes a potential impact pathway to this receptor.

Habitats

7.5.13 Figures 7.3 a-d show the habitats identified during the Phase 1 habitat surveys of the study area. Summaries of these habitat types and their coverage of the field study area, calculated by GIS, are given below.

7.5.14 Where the habitats described in the following sections occur within the LOD for the Proposed Development as well as the field study area this clearly stated.

7.5.15 The “area surveyed” is referred to rather than the “field study area” as habitat surveys were undertaken around the proposed alignment at the time of survey. This did not always adhere to the defined field study area.

Broadleaved Plantation Woodland

7.5.16 A small area of broadleaved planting was identified in the corner of one field at South Weydale. As the trees were still immature, species identification was difficult but some Betula sp. was present over semi-improved neutral grassland. A total of 3.51 ha of this habitat was recorded, 0.16% of the total area surveyed.

Semi-natural Coniferous Woodland

7.5.17 A small area of conifer regeneration was observed on Moss of Greenland (Figure 7.3c). Here young Norway spruce Picea abies that have seeded on the bog were observed growing in a small stand. A total of 2.70 ha of this habitat was recorded, 0.12% of the total area surveyed.

Coniferous Plantation Woodland

7.5.18 The eastern end of the study area is dominated by young Norway spruce plantation. The trees here were all less than eight metres in height with very limited understorey. A total of 174.29 ha of this habitat was recorded, 7.7% of the total area surveyed.

7.5.19 12.67 ha of this habitat is found within the LOD for the Proposed Development, 4% of the total area.

Mixed Plantation Woodland

7.5.20 An area of mixed plantation woodland exists at the western end of the LOD, next to the Proposed Thurso South Substation. A shelter belt has been planted here consisting of Holly Ulex aquilinium, Pinus sp. and some unidentified broadleaved species. A total of 2 ha of this habitat was recorded, 0.09% of the total area surveyed.

Scrub

7.5.21 Areas of Gorse Ulex europaeus and Broom Cytisus scoparius scrub are found throughout the study area in both dense and scattered forms. These habitats are


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very homogenous with a limited understorey. A total of 6.31 ha of this habitat was recorded, 0.28% of the total area surveyed.

7.5.22 3.71 ha of this habitat is found within the LOD for the Proposed Development, approximately 1% of the total area.

Acid Grassland

7.5.23 Areas of acid grassland were identified on site in both semi-improved and unimproved states. Acid grasslands are typified by the presence of heath bedstraw Galium saxatile and tormentil Potentilla erecta beneath graminoids such as wavy-hair grass Deschampsia flexuosa, mat grass Nardus stricta and heath rush Juncus squarrosus. A total of 25.44 ha of this habitat was recorded, 1.12% of the total area surveyed.

Neutral Grassland

7.5.24 The most commonly encountered habitat within the study area was semi-improved neutral grassland. This was most commonly seen in pasture fields that had not been subject to intensive improvement. Key species include false-oat grass Arrhenatherum elatius, crested dog’s tail Cynosurus cristatus and cock’s foot Dactylis glomerata. A total of 560.17 ha of this habitat was recorded, 24.74% of the total area surveyed.


Improved Grassland

7.5.26 Improved grassland was another commonly observed habitat within the area surveyed. This habitat is found in pasture fields that have been heavily enriched by fertilisers or by grazing livestock. It is characterised by the appearance of high quantities of perennial rye grass Lolium perenne as well as forbs such as white clover Trifolium repens. A total of 384.58 ha of this habitat was recorded, 16.99% of the total area surveyed.


Marshy Grassland

7.5.28 Large areas of marshy grassland were also identified during the surveys. This habitat includes wet ground covered by Juncus sp. as well as some shallow peat soils dominated by purple-moor grass Molinia caerulea. Rushes are quick to colonise disturbed or waterlogged land and so are frequently observed in heavily managed areas. A total of 546.11 ha of this habitat was recorded, 24.12% of the total area surveyed.

7.5.29 54.28 ha of this habitat is found within the OHL LOD for the Proposed Development, approximately 19% of the total area.

Dry Heath

7.5.30 Dry heath describes areas dominated by ericoid dwarf shrubs such as heather Calluna vulgaris and cross-leaved heath Erica tetralix. It is found in areas of shallow or no peat and is generally found in more upland terrain than that observed


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in the study area; where it was observed at a low frequency. A total of 30.71 ha of this habitat was recorded, 1.36% of the total area surveyed.


Wet Heath

7.5.32 Wet heath was also recorded at low levels in the study area. Again this can be found on shallow peat soils, or areas with no peat, and has a greater than 25% cover of ericoids. Wet heath differs from dry heath by having higher levels of purple-moor grass and a more specific sphagnum composition; Sphagnum compactum and S. tenellum are frequent. A total of 55.79 ha of this habitat was recorded, 2.46% of the total area surveyed.

Wet Modified Bog

7.5.33 The study area crosses three main areas of wet modified bog: Moss of Tain, Moss of Greenland and Hollandmey Moss. These bogs are found on areas with peat deeper than 0.5 m and generally contain no sphagnum due to disturbances such as peat cutting, draining or tree regeneration. Common species observed include hares’-tail cottongrass Eriophorum vaginatum, cross-leaved heath and heather. A total of 265.35 ha of this habitat was recorded, 11.72% of the total area surveyed.


Dry Modified Bog

7.5.35 This habitat describes bogs over deeper peat that have dried up as a result of draining. Sphagnum species are notably absent with ericoids and graminoids dominating; here heather, purple-moor grass and wavy-hair grass found over a sparse carpet of Kindbergia praelonga. A total of 13.22 ha of this habitat was recorded, 0.58% of the total area surveyed.

Other Habitats

7.5.36 The remaining 8.56% of habitats in the area surveyed is made up of open water (0.03%), arable farmland (5.65%) and bare ground (2.89%). Arable farmland makes up the rest of the habitats found within the LOD, 16.30 ha or approximately 6%.

NVC Survey

7.5.37 The targeted NVC survey was carried out at 15 points within the study area –at the points marked on Figure 7.4. This resulted in the description of an indicative NVC community for the surrounding area and with it a more accurate description of the potential for groundwater dependency. Consideration of the baseline hydrology and hydrogeology associated with these habitats is included within Chapter 10: Geology, Hydrology and Hydrogeology.

7.5.38 The results of this survey are shown as a series of points labelled on Figure 7.4 along with identified areas of high and moderate groundwater dependence based


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on identified communities, as described by the Scottish Environment Protection Agency SEPA22. Summaries of the communities recorded are given below.

M15 - Scirpus cespitosus - Erica tetralix wet heath

7.5.39 This wet heath community was observed at three locations around the field study area. It is represented by cross-leaved heath, heather and deergrass Trichophorum germanicum dominating over occasional species such as bog asphodel Narthecium ossifragum, glaucous sedge Carex flacca and purple-moor grass.

7.5.40 This community is classified as being moderately groundwater dependent for this assessment, in line with the SEPA23 classifications. This habitat was recorded within the LOD for the Proposed Development and is ubiquitous within Caithness with the examples recorded being somewhat degraded.

M17 - Scirpus cespitosus - Eriophorum vaginatum blanket mire

7.5.41 There were two locations identified as being M17, both located on Moss of Greenland. M17 is characterised by the high abundance of hare's-tail cottongrass, which is dominant over vascular species such as cross-leaved heath, heather, common cotton grass Eriophorum angustifolium and glaucous sedge. Moss species Sphagnum fallax, S. palustre and Aulacomnium palustre were also recorded.

7.5.42 M17 is not classified under the GWDTE system as it is a rainwater dependent (ombrogenous) community. This community was recorded within the LOD for the Proposed Development and is common across much of Caithness. The examples recorded were of good quality.

M19 - Calluna vulgaris - Eriophorum vaginatum blanket mire

7.5.43 M19 was observed on Moss of Greenland and Hollandmey Moss. It is identified by the mixture of hare's-tail cotton grass and ericoid species, notably heather, and generally lower quantities of sphagnum. Other species recorded included devil's-bit scabious Succisa pratensis, tormentil and small amounts of Sphagnum capillifolium.

7.5.44 This is another ombrogenous community that is not groundwater dependent. This community was recorded within the LOD for the Proposed Development and is another common bog community in Caithness. The examples recorded were degraded by grazing activities.

M23 - Juncus effusus/acutiflorus - Galium palustre rush pasture

7.5.45 M23 rush pasture was observed at four locations within the LOD of the Proposed Development; at Weydale, Reaster, Hollandmey and Philips Mains. The classification contains vegetation characterised by an abundance of soft rush Juncus effusus and sharp-flowered rush J. acutiflorus. This includes most of the rush rich vegetation over disturbed ground that is classified as marshy grassland under the Phase 1 habitat classification system. It can also include areas dominated by purple-moor grass over peat shallower than 0.5 m.

22 Land Use Planning System, SEPA Guidance Note 31: Guidance on Assessing the Impacts of Development Proposals on

Groundwater Abstractions and Groundwater Dependent Terrestrial Ecosystems (SEPA, 2014) 23 SEPA (2014) Land Use Planning System: SEPA Guidance Note 4


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7.5.46 This community is classified as being highly groundwater dependent for this assessment, in line with the SEPA classifications. This community is present within the LOD for the Proposed Development, but is represented by poor quality examples where Juncus effusus has come to dominate over nutrient poor, disturbed ground.

M25 - Molinia caerulea - Potentilla erecta mire

7.5.47 This community is often observed as purple-moor grass dominating over tussocky ground on peat soils deeper than 0.5 m. It was observed at two locations near the LOD and also included species such as cross-leaved heath, sweet vernal grass Anthoxanthum odoratum and tormentil.

7.5.48 This community is classified as being moderately groundwater dependent for this assessment, in line with the SEPA classifications. This is another common NVC community that was found within the LOD for the Proposed Development. The examples present are of good quality.

U2 - Deschampsia flexuosa grassland

7.5.49 This upland acidic grassland community is dominated by wavy-hair grass and was observed over a species assemblage including mat grass, tormentil and heath bedstraw. It was identified on higher ground at Weydale Moss.

7.5.50 U2 is not classified as a groundwater dependent by SEPA. This community was not recorded within the LOD for the Proposed Developments.

Desk Study

7.5.51 The desk study carried out in March 2011 and May 2014 identified species that were present within five km of the Proposed Development (the desk study buffer as shown on Figure 7.1). Table 7.4, below, shows records from within 1 km of the LOD for the Proposed Development. The full desk study results are given in Technical Appendix 7.3.

Table 7.4: Desk Study Results within LOD of Proposed Development

Species Location Distance for LOD Source

Otter Lochend, Lucifer Moss, Durrans Mains

Within LOD, 1 km and 1km respectively

NBN Gateway/Lochend Windfarm ES/Durran Mains ES

Water Vole Hollandmey Moss and Durrans Mains

Within LOD and 1km respectively

NBN Gateway/ Lochend Windfarm ES/Durran Mains ES

Pine Marten Durrans Mains 1km Durran Mains ES

Scottish Wildcat

Phillipps Mains 1km NBN Gateway

Common Pipistrelle

Lochend Within LOD Lochend Windfarm ES

Protected Species Surveys

7.5.52 Results of the protected species surveys are shown on Figure 7.5.


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Otter

7.5.53 Otters are known to be present within the study area based on data collated during the desk study and from reference to the River Thurso SAC designation. Otter spraints were recorded twice during the protected species survey, both times to the east of Syster farm. No holts or couches were recorded during the surveys.

7.5.54 Otters are known to be present across the field study area but the low level of field signs recorded and the low level of suitable habitat away from the watercourses would suggest that local populations are small.

Water Vole

7.5.55 Water vole droppings and burrows were recorded around Burn of Ormigill during the protected species surveys. Here the habitat is very suitable with purple-moor grass tussocks growing around a small, slow flowing burn. When the area was resurveyed in 2013 no signs were recorded. A separate survey by the Caithness Biodiversity Group concluded that there was a wide distribution of water voles in Caithness24.

7.5.56 The water vole presence within the field study area is limited to pockets at Durran Mains and between Syster and Phillipps Mains.

Bats

7.5.57 Common pipistrelle is a Caithness BAP species and is known to be present within the study area based on data collated during the desk study. No potential roosting sites were recorded during the protected species survey and there is a lack of suitable foraging sites around woodland within the field study area.

Fish Species

7.5.58 No direct survey of fish species was completed. The River Thurso SAC was designated for its Atlantic salmon and as such, for the purposes of this assessment, it is considered that it continues to support a healthy fish population.

Receptor Evaluation

River Thurso SAC/Atlantic Salmon

7.5.59 The River Thurso SAC supports an internationally important population of Atlantic salmon and as such, for the purposes of this assessment, is considered to be of international value. Atlantic salmon within the SAC are also considered to be of international value.

Other Designated Sites

7.5.60 The three SSSIs identified in close proximity to the Proposed Development were all notified for their biological interests and importance in the region: Loch Heilen SSSI for its mesotrophic loch; Loch of Durran SSSI for its vascular plant assemblage including endemic small reed species and wetland transitional grassland; and the River Thurso SSSI for its floodplain meadow habitats. These sites are considered to be of national value.

24 Fraser, E, Glass, D and Hogg, S (2005) The Distribution of the Water Vole in Caithness, Caithness Biodiversity Group


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Habitats

7.5.61 There are 25 areas of habitat considered to be GWDTE that the LOD of the Proposed Development crosses and for the purposes of this assessment, these are considered to have regional value.

7.5.62 The grassland habitats along the LOD for the Proposed Development are dominated by pastureland. Grazing by sheep and cattle has led to a reduction in the species diversity of the grassland swards and a trend towards more neutral conditions from the acidic ones that once dominated. There are examples of Caithness BAP habitat types such as purple moor-grass rush pasture and arable fields but they are poor examples not supporting many of the features for which the habitat types were included in the BAP. For the purposes of this assessment, the grassland habitats are considered to have local value.

Otter

7.5.63 Otter is a widespread species in Caithness and recorded on most watercourses. Otter is listed on Annex II of the Habitats Directive and is a notable, though not qualifying feature of the River Thurso SAC which lies to the west of the western extent of the LOD. However, no holts or couches were recorded during field surveys. As such, for the purposes of this assessment, otter is considered to be of regional value.

Water Vole

7.5.64 Water voles are listed in Schedule 5 of the Wildlife and Countryside Act due to their dramatic population decline. Upland streams are one of few remaining strongholds for the species which is threatened by American mink Mustela vison and habitat degradation throughout much of the lowlands. However given existing baseline data which indicates a large and stable Caithness population, and considering few field signs were observed, water voles are considered to be of district value.

Reptiles and Amphibians

7.5.65 All of the common reptiles and amphibians are considered likely to be present within suitable habitat along the LOD of the Proposed Development including the Caithness BAP species, common lizard, adder, common frog and common toad. However, opportunities for them to be present are limited by a lack of available habitat and habitat connectivity so any populations are considered to be of local value.

7.6 Potential Impacts

7.6.1 The impacts described below are potential impacts that could result from the Proposed Development if no mitigation were to take place. Mitigation to avoid these impacts is in section 7.7 and the assessment of the post mitigation impacts is in section 7.8.

OHL

Potential OHL Construction Impacts

DEGRADATION OF DESIGNATED SITES

7.6.2 Accidental releases of silt, fuel or lubricants during the construction phase may indirectly degrade the condition of the River Thurso and the qualifying features of


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the SAC and SSSI by affecting biological and chemical water quality and the physical character of substrates. Tributaries that flow into the River Thurso cross the LOD for the Proposed Development and have the potential to carry pollutants into the SAC and SSSI. In addition, the Loch of Durran SSSI would have potential to be affected by similar pathways. In most cases, degradation would be temporary. More information of effects on water quality can be found in Chapter 10: Geology, Hydrology and Hydrogeology.

HABITAT DESTRUCTION OR DEGRADATION

7.6.3 Construction activities have the potential to degrade or destroy terrestrial habitat either directly as a result of, for example, excavation, compaction, or modification (e.g. vegetation removal, covering) or indirectly as a result of, for example, dewatering, or from the accidental release of fuels, lubricants or other chemicals. Construction activities have the potential to indirectly degrade aquatic habitats as a result of accidental releases of silt, fuel, lubricants or chemicals. Some construction activities could cause permanent degradation or destruction, for example where tower foundations are constructed or permanent new access tracks are formed, but in most cases, impacts would be temporary.

DISTURBANCE TO OTTER AND WATER VOLE

7.6.4 Construction activities giving rise to noise, vibration and light may directly disturb otter and water vole using the habitats around the LOD. Accidental releases of pollutants to the river may cause indirect effects by affecting water quality or food sources. These impacts would be adverse, short term and reversible.

DISTURBANCE OF AMPHIBIANS AND REPTILES

7.6.5 Construction activities could result in direct disturbance of individual amphibians and reptiles. Construction activities also have the potential to degrade or destroy amphibian and reptile habitat as described above.

Potential OHL Operational Impacts

7.6.6 During the operational phase, maintenance activities would involve regular tower inspections, insulators replacement etc. In all cases, maintenance activities would access the Proposed Development from access tracks established during construction. No activities giving rise to ecological impacts are identified.

Underground Cable

Potential Underground Cable Construction Impacts

DEGRADATION OF DESIGNATED SITES

7.6.7 It is proposed to connect the Sealing End Compound at Weydale, to the proposed Thurso South substation at the western extent of the LOD for the Proposed Development through the installation of an underground cable. The process of installing the cable (as described in Chapter 2) has the potential for releasing silt, fuel or lubricants into the River Thurso catchment with the potential for causing a temporary effect on the qualifying interests of the SAC.

7.6.8 Accidental releases of silt, fuel or lubricants during the construction phase may indirectly degrade the condition of the River Thurso and the qualifying features of the SAC and SSSI and Loch Heilen SSSI by affecting biological and chemical water quality and the physical character of substrates. In most cases, degradation


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would be temporary. More information of effects on water quality can be found in Chapter 10: Geology, Hydrogeology and Hydrology.

HABITAT DESTRUCTION OR DEGRADATION

7.6.9 Construction activities have the potential to degrade or destroy terrestrial habitat either directly as a result of, for example, excavation, compaction, or modification (e.g. vegetation removal, covering) or indirectly as a result of, for example, dewatering, or from the accidental release of fuels, lubricants or other chemicals. Some aquatic habitats may be degraded indirectly as a result of accidental releases of silt, fuel, lubricants or chemicals with this having an adverse effect on the otter population present. These activities would cause temporary degradation or destruction where access tracks are constructed.

7.6.10 In particular the construction activities have the potential to degrade or destroy areas of GWDTE. Groundwater processes can be disturbed by compaction and excavation activities with this being a temporary impact.

DISTURBANCE TO OTTER AND WATER VOLE

7.6.11 Construction activities giving rise to noise, vibration and light may directly disturb otter and water vole using the habitats around the LOD. Accidental releases of pollutants to the river may cause indirect effects by affecting water quality or food sources. Mammals can get fall into and get trapped inside excavation areas. These impacts would be adverse, short term and reversible.

DISTURBANCE OF AMPHIBIANS AND REPTILES

7.6.12 Construction activities may result in direct disturbance of individual amphibians and reptiles. Construction activities also have the potential to degrade or destroy amphibian and reptile habitat as described above.

Potential Underground Cable Operational Impacts

7.6.13 There are no impacts associated with the operational phase of the Proposed Developments.

7.7 Mitigation

7.7.1 Mitigation for the Proposed Development is of two main types: • Mitigation by design – the design of the route and connection option, as

described in Chapter 4, was informed by ecological considerations. This considered both the OHL and underground sections of the route.

• Mitigation during construction – measures would be incorporated into the Construction Environmental Management Document (CEMD) or the Construction Environmental Management Plan (CEMP), as listed in the Schedule of Mitigation in Chapter 14, which would ensure good practice mitigation measures were employed.

7.7.2 A hierarchical approach to ecological mitigation has been adopted by the Proposed Development, as follows: • Impact Avoidance.

• Impact Reduction.

• Impact Offsetting (Compensation).


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• Enhancement Measures.



AVOIDANCE OF DESIGNATED SITES

7.7.3 The location and definition of the LOD for the Proposed Development has been informed by various routing principles, which, amongst other things, have sought to avoid and reduce impacts on features of nature conservation importance identified during the ecological surveys. Chapter 4: Route Selection and Alternatives summarises the LOD selection process.

7.7.4 The LOD for the Proposed Development avoids the Loch of Durran SSSI by at least 800 m.

AVOIDANCE OF SENSITIVE HABITATS

7.7.5 The LOD for the Proposed Development have been designed to lie predominantly in agricultural land, comprising improved and semi-improved grassland. Sensitive habitats represented by Caithness BAP habitat types (purple moor grass and rush pasture) have been avoided as far as possible whilst balancing the needs of landowners for agricultural land not to be sterilised.

MICROSITING OF TOWER LOCATIONS (AVOIDANCE)

7.7.6 Eventual micrositing of towers within the LOD would seek to avoid localised ecological sensitivities wherever possible. These include, but would not be limited to, watercourses, habitats with increased sensitivity to disturbance such as GWDTE or mammal locations.


AVOIDANCE OF DESIGNATED SITES

7.7.7 The alignment of the underground cable element of the Proposed Development has been informed by various routing principles, which, amongst other things, have sought to avoid and reduce impacts on features of geological, hydrogeological or hydrological importance such as surface water features and areas of GWDTE identified during the ecological surveys.

7.7.8 The Underground Cable LOD lies at least 450 m from Loch Heilen SSSI.

AVOIDANCE OF SENSITIVE HABITATS

7.7.9 The Underground Cable LOD lies predominantly in agricultural land, comprising improved and semi-improved grassland. Sensitive habitats represented by CBAP habitat types (purple moor grass and rush pasture) and GWDTE are avoided wherever possible. Where this has not been possible due to other environmental constraints on routeing, impacts have been reduced.


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Mitigation during Construction


TIMINGS OF WORKS (AVOIDANCE)

7.7.10 To reduce the levels of disturbance on ecological receptors, works would be undertaken outwith sensitive seasons. Wherever practicable tasks would be planned in advance to be undertaken in a manner that reduces the potential impact on ecological receptors. An example of this would be removal of scrub vegetation outwith the main bird breeding season of April to August inclusive.

REDUCTION OF ACCESS TRACK IMPACTS ON GROUNDWATER DEPENDENT TERRESTRIAL ECOSYSTEMS (REDUCTION)

7.7.11 Prior to construction, the approach to the detailed access strategy design and track construction in and around the identified GWDTE would have due regard to key principles set out in the joint SNH/FCS guide to floating roads on peat and adherence to best practice in track construction, including; use of temporary track where possible; use of the minimum length of track possible within these sensitive habitats; and tracks would be constructed using floating road techniques.

7.7.12 The following location specific measures would be followed: • where the new stone road at Achingills crosses areas of high groundwater

dependence (in 135 metre and 38 metre sections) construction will incorporate sub-track drainage to allow continued movement of groundwater within these habitats;

• sections of temporary road south of Fryster that cross areas of high groundwater dependence (sections of 265 m, 110 m and 170 m) will incorporate sub-track drainage to allow continued movement of groundwater within these habitats;

• sections of temporary road north of Bowermadden that cross areas of high groundwater dependence (sections of 770 m and 420 m) will incorporate sub-track drainage to allow continued movement of groundwater within these habitats;

• a 38m long stretch of floating road will be constructed to the south of Moss of Greenland which will incorporate sub-track drainage to ensure the hydrological connectivity of the habitat remains intact;

• the section of temporary road north-west of Reaster that crosses the area of moderate groundwater dependence (a section of 490 m) will incorporate sub-track drainage to allow continued movement of groundwater within these habitats; and

• where the new stone road north of Reaster crosses areas of high and moderate groundwater dependence (a 635 m section) sub-track drainage will be incorporated to allow continued movement of groundwater within these habitats.

REMOVAL AND STORAGE OF TURFS IN SENSITIVE HABITATS

7.7.13 In any areas such as ombrogenous peat bogs or wet heaths, which would be temporarily disturbed for access tracks or construction compounds, turfs of peatland vegetation would be removed and set aside for later use in restoration.


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WATERCOURSE POLLUTION AND SILTATION PREVENTION MEASURES (AVOIDANCE)

7.7.14 All watercourses within the LOD would have 75m buffers established during the construction phase, within which construction activities would only occur under protection measures, see paragraph 7.7.15. These include but are not limited to: • Burn of Achingills and its tributaries;

• Burn of Durran and its tributaries; and

• Burn of Hunster and its tributaries.

7.7.15 Pollution spill kits and silt entrapment measures would be provided at all work sites within 75m of water courses and all personnel would be trained in their deployment. Other measures employed would include bunding of all construction liquids such as fuel or hydraulic fluids and creation of interceptor drains around tower construction locations to remove potential pathways to the River Thurso. The Principal Contractor's depot(s) would be located in a contained location away from any environmental sensitivities.

PRODUCTION OF CONSTRUCTION ENVIRONMENTAL MANAGEMENT DOCUMENT AND SITE CONSTRUCTION ENVIRONMENTAL MANAGEMENT PLANS (REDUCTION)

7.7.16 A CEMD (containing individual Construction Environmental Management Plans (CEMPs)) would be prepared defining the methodologies and management measures to be employed in the construction of the Proposed Development. These are listed in the Schedule of Mitigation in Chapter 14.

7.7.17 The CEMP would contain management plans and proposals consistent with those agreed by the Applicant with THC, SEPA, SNH and Historic Scotland on other recent construction projects. Specifically it would provide details of the access points and routes to be utilised to reach each work location, pollution prevention control measures, particularly in relation to watercourses and the location of construction work areas such as site compounds and storage areas. The mitigation measures which have informed the assessment in this chapter are listed in Chapter 14. As part of the CEMD, site CEMPs would be prepared for sections of the Proposed Development and would identify potential environmental risks and mitigation measures for each key site activity as part of producing detailed EMPs and Method Statements before construction in each area begins.

7.7.18 An Environmental Clerk of Works (ECoW), working with the Applicant's Environmental Project Manager, would be appointed to ensure that all ecological mitigation measures are adhered to during construction.

PRE-CONSTRUCTION PROTECTED SPECIES SURVEY

7.7.19 Prior to work commencing a protected species survey, similar to the one undertaken during this assessment, would be undertake along the proposed alignment. This would identify and protected species using the habitats of the Proposed Development that were not present when surveyed for here. A suitably qualified ecologist would be appointed to undertake this survey.

PRE-CONSTRUCTION REPTILE AND AMPHIBIAN SURVEY

7.7.20 Prior to work commencing to clear areas of habitat on site where reptiles or amphibians may be found, the suitably qualified ecologist would search these areas for their presence. Any individuals located within the area would be moved


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out with the construction corridor. If the work is undertaken out with the active months for the species then the ecologist would search for suitable hibernation sites for relocation. If species are found, measures to avoid their mortality would be undertaken.

ADDITIONAL MITIGATION

7.7.21 Any excavations which remain uncovered overnight would have mammal ladders deployed to prevent otters and other species from becoming trapped. Additionally all pipes would be capped and chemicals stored securely.

7.7.22 The CEMD would contain specific Species Protection Plans (SPP) for Otters and Reptiles and Amphibians. Further details relating to individual mitigation measures identified in response to specific impacts are set out as part of the discussion of residual impacts in section 7.8 below.


AVOIDANCE OF DESIGNATED SITES (AVOIDANCE)

7.7.23 The Proposed Development avoids construction within any designated sites. Where works are required within 75 m of watercourses that are tributaries of the River Thurso, such as the drains in Weydale, or watercourses that flow into Loch Heilen, detailed method statements and risk assessments would be developed by the Principal Contractor. All compounds would be located, designed and constructed to avoid impacts to the watercourses to avoid any potential pathways for pollutants into the River Thurso SAC.

TIMINGS OF WORKS (AVOIDANCE)

7.7.24 To reduce the levels of disturbance on ecological receptors, works would be undertaken outwith sensitive seasons. Wherever practicable tasks would be planned in advance to be undertaken in a manner that reduces the potential impact on ecological receptors. An example of this would be removal of scrub vegetation outwith the main bird breeding season of April to August inclusive.

WATERCOURSE POLLUTION AND SILTATION PREVENTION MEASURES (AVOIDANCE)

7.7.25 All watercourses within the LOD of the Proposed Development would have buffers established during the construction phase, within which construction activities would only occur under strict protection measures, given in paragraph 7.7.26. These include but are not limited to: • Drains flowing into the River Thurso from Weydale;

• Burn of Reaster and its tributaries;

• Link Burn and its tributaries; and

• Burn of Ormigill and its tributaries.

7.7.26 Pollution spill kits and silt entrapment measures would be provided at all work sites within 75m of water courses and all personnel would be trained in their deployment. Other measures employed would include bunding of all construction liquids such as fuel or hydraulic fluids and creation of interceptor drains around tower construction locations to remove potential pathways to the River Thurso. The Principal Contractor's depot(s) would be located in a contained location away from any environmental sensitivities.


LT000022 7-25 Chapter 7:

Ecology

PRODUCTION OF CONSTRUCTION ENVIRONMENTAL MANAGEMENT DOCUMENT AND SITE SPECIFIC CONSTRUCTION ENVIRONMENTAL MANAGEMENT PLANS (REDUCTION)

7.7.27 As listed above a CEMD would be prepared defining the methodologies and management measures to be employed in the construction of the Proposed Development. These are listed in the Schedule of Mitigation in Chapter 14.

7.7.28 The CEMP would contain management plans and proposals consistent with those agreed by the Applicant with THC, SEPA, SNH and Historic Scotland on other recent construction projects. Specifically it would provide details of the access points and routes to be utilised to reach each work location, pollution prevention control measures, particularly in relation to watercourses and the location of construction work areas such as site compounds and storage areas. The mitigation measures which have informed the assessment in this chapter are listed in Chapter 14. As part of the CEMD, site specific CEMPs would be prepared for sections of the Proposed Development and would identify potential environmental risks and mitigation measures for each key site activity as part of producing detailed CEMPs and Method Statements before construction in each area begins.

PRE-CONSTRUCTION REPTILE AND AMPHIBIAN SURVEY

7.7.29 Prior to work commencing to clear areas of habitat on site where reptiles or amphibians may be found, the ecologist would search these areas for their presence. Any species located within the area would be moved out with the construction corridor. If the work is undertaken outwith the active months for the species then the ecologist would search for suitable hibernation sites for relocation. If species are found, measures to avoid their mortality would be undertaken potentially including micrositing of features associated with the Proposed Development in consultation with SNH.

ADDITIONAL MITIGATION

7.7.30 Any excavations which remain uncovered overnight would have mammal ladders deployed to prevent otters and other species from becoming trapped. Additionally all pipes would be capped and chemicals stored securely.

7.7.31 The CEMD would contain specific SpPPs for Otters and Reptiles and Amphibians. Further details relating to individual mitigation measures identified in response to specific impacts are set out as part of the discussion of residual impacts in section 7.9 below.


7.7.32 There are no mitigation measured proposed for the operational phase of the Proposed Development.

7.8 Assessment of Residual Impacts

7.8.1 This section details the residual impacts on ecological receptors taking into account the mitigation measures described above.


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Residual Construction Impacts - OHL

Residual Construction Impact: Degradation of Designated Sites

ASSESSMENT OF RESIDUAL IMPACT AND RESIDUAL SIGNIFICANCE

7.8.2 Adopting the mitigation measures listed above, an ecological significant impact on the SAC and qualifying features will be extremely unlikely (<5%). Likewise, an ecologically significant impact on the SSSI will also be extremely unlikely (<5%). Impacts on both receptors would be low magnitude, localised, short term and reversible.

Residual Construction Impact: Habitat Destruction or Degradation


7.8.3 With the completion of the mitigation detailed in this chapter an ecologically significant adverse impact on habitats is considered to be extremely unlikely. Impacts would be low magnitude, localised short term and reversible.

Residual Construction Impacts - Underground Cable

Residual Impact: Underground Cable Installation on River Thurso SAC, SSSI and qualifying interests


7.8.4 Adopting the mitigation measures listed above, an ecological significant impact on the SAC and qualifying features will be extremely unlikely (<5%). Likewise, an ecologically significant impact on the SSSI will also be extremely unlikely (<5%). Impacts on both receptors would be low magnitude, localised, short term and reversible.

Residual Construction Impact: GWDTE


7.8.5 With the completion of the mitigation detailed in this chapter an ecologically significant adverse impact on GWDTE from the underground cable construction is considered to be extremely unlikely. Impacts would be low magnitude, localised short term and reversible.

7.8.6 The underground cable element of the Proposed Development cross an area at Hollandmey Moss identified as potential GWDTE. Whilst this area is considered potentially moderate GWDTE based on NVC classification, further field investigation has confirmed that these habitats are likely to be of low ecological value for GWDTE. In this example the habitats comprise wet modified bog already degraded by agricultural land practice of draining and grazing (see chapter 11). Based on the observed assemblage it is also considered likely to be at least partially rain-water dependent.

7.8.7 As a result significant residual impacts on GWDTE are not expected.


LT000022 7-27 Chapter 7:

Ecology

Residual Construction Phase Impact: Underground Cable Installation Disturbance of Otter and Water Vole


7.8.8 With the provision of the above named mitigation during the construction of the Proposed Development, an ecologically significant adverse residual impact is considered extremely unlikely. This impact would be low magnitude, localised, short term and reversible.

Residual Operational Impacts

7.8.9 No residual operational phase impacts have been identified.


7.9.1 Cumulative impacts are considered to be limited to impacts on habitats in the form of habitat loss or degradation. The majority of the cumulative developments, as identified within Chapter 3: EIA Process and Methodology are wind farms and their associated infrastructure on the type of peatland dominated habitats that the Proposed Development has attempted to avoid as far as possible. In the same way as the Proposed Development, the landtake of wind farms is limited to access tracks and specific construction footprints (for turbines instead of towers) and the majority of the habitats within the overall site area of the identified cumulative development would not be impacted. Indeed, best practice in wind farm design is for turbine locations and access track routes to avoid the most sensitive habitats, particularly those associated with peaty substrates or those which are dependent on particular water levels.

7.9.2 Key developments considered for their cumulative effects include the Thurso South Substation, the Dounreay - Mybster 275kV OHL and the Stroupster wind farm which have all been consented as well as the Meygen Tidal Power Conversion Centre which has been submitted for planning permission. Wind farms in pre-planning and single turbine developments have also been included.

7.9.3 The Thurso South Substation is situated at the western end of the Proposed Development in an area dominated by unimproved acid grassland. The Dounreay - Mybster 275kV OHL crosses similar habitats to the Proposed Development; namely semi improved/improved grassland, marshy grassland and wet heath, and was designed to avoid sensitive habitats. The Meygen Tidal Power Conversion Centre is located on the coast and does not involve the loss of habitats recorded within the LOD of the Proposed Development.

7.9.4 Habitats affected by the installation of the wind farms planned for the area surrounding the Proposed Development include areas of modified bog, improved grassland, dry heath and conifer plantation. These are very common habitats in the region with potential land take from all projects making up a small proportion of their total area. As such, there is not considered to be a significant cumulative impact on the habitats of the site.

7.9.5 The proposed Thurso South substation site lies within 80 m of the River Thurso SAC. As such potential pollution and siltation impacts similar to those assessed for the Proposed Development are possible from the construction of that development. Similar mitigation measures would be required as on the Proposed Development to prevent pollution or silt entering the river.


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7.9.6 According to the publicly available Environmental Statements and other environmental reports a low level of protected terrestrial species activity has been recorded by the surveys in support of the other cumulative schemes in the area and as such no significant cumulative impacts on species such as otter are considered to exist.

7.10 Summary of OHL Impacts

7.10.1 The Ecological Impact Assessment (EcIA) considered potential impacts on ecological receptors such as protected species and habitats in line with best practice guidance on EcIA from the CIEEM. The assessment has considered national, regional and local policy including the Habitats Directives, Wildlife and Countryside Act and Caithness Biodiversity Action Plan.

7.10.2 The field study area (the LOD of Proposed Development (OHL and underground cable) plus a wider corridor – approximately two km) was surveyed in 2011, and again in 2012 and 2013 to provide baseline information on habitats and species. Surveys include phase 1 habitat survey, NVC Survey, and protected species survey.

7.10.3 The principal habitats within the LOD of the OHL are semi-improved neutral, improved and marshy grassland. Much of the site is considered to be of low ecological value as it is dominated by species poor farmland.

7.10.4 Mitigation measures have been designed to, as far as possible, avoid impact on the habitats and species found within and close to the LOD of the OHL. A number of compensatory measures (as included in Chapter 14: Schedule of Mitigation) would be completed to help ensure that there is no net negative impact on biodiversity.

7.10.5 Although prior to mitigation there would be some negative impacts as a result of the construction of the OHL, incorporation of mitigation would reduce residual impacts. Following construction it is anticipated that the landtake of the OHL and wider study area would remain or return to similar to the current baseline, supporting livestock grazing. It would encompass a viable network of habitats and support sustainable populations of the species currently present. A summary of mitigation proposed and residual impacts arising from the OHL aspect of the Proposed Development is listed in Table 7.5.

Table 7.5: Summary of Potential Impacts of the Proposed Development, Mitigation and Residual Impacts of the OHL

Potential Impact Mitigation Proposed

Means of Implementation

Outcome/Residual Impact

Construction

Degradation of Designated Sites

Avoidance (design and construction) and Watercourse Pollution and Siltation Prevention Measures (construction)

LOD defined to avoid designated sites. Buffers around watercourses.

Extremely Unlikely


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Potential Impact Mitigation Proposed



Habitat Destruction or Degradation

Avoidance (design and construction), Micrositing (design) and Timing (construction).

LOD defined to avoid key habitats. Towers microsited to avoid key habitats. Works timed to avoid impacts on ecology.

Extremely Unlikely

Disturbance of Amphibians and Reptiles

Pre-construction Survey (construction).

Suitably qualified ecologist would survey site prior to construction activities.

None

Operation

N/A N/A N/A N/A

7.11 Summary of Underground Cable Impacts

7.11.1 The principal habitats within the LOD of the underground cable are semi-improved neutral, improved and marshy grassland. Much of the site is considered to be of low ecological value as it is dominated by species poor farmland.

7.11.2 Protected species recorded within the study area during ecological surveys include European otter and water vole.

7.11.3 Mitigation measures have been designed to, as far as possible, avoid impacts on the habitats and species found within and close to the LOD of the underground cable. A number of compensatory measures would be completed to help ensure that there is no net negative impact on biodiversity.

7.11.4 Although prior to mitigation there would be some negative impacts as a result of the construction of the underground cable, incorporation of mitigation measures would reduce residual impacts. Following construction it is anticipated that the landtake of the cabling and wider study area would remain or return to habitat similar to the current baseline, supporting livestock grazing. It would encompass a viable network of habitats and support sustainable populations of the species currently present. A summary of mitigation proposed and residual impacts arising from the underground cable aspect of the Proposed Development is listed in Table 7.6.


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Table 7.6: Summary of Potential Impacts of the Proposed Development, Mitigation and Residual Impacts of the Underground Cable

Potential Impact Mitigation Proposed Means of Implementation


Construction

Degradation of Designated Sites

Avoidance (design and construction) and Watercourse Pollution and Siltation Prevention Measures (construction)

LOD defined to avoid designated sites. Buffers around watercourses.

Extremely Unlikely

Habitat Destruction or Degradation (including GWDTE)

Avoidance (design and construction) and Timing (construction)

LOD defined to avoid key habitats. Works timed to avoid impacts on ecology.

Extremely Unlikely

Disturbance of Amphibians and Reptiles

Pre-construction Survey (construction)

Suitably qualified ecologist would survey site prior to construction activities.

None

Other Construction Impacts

Production of CEMD and Site Specific Environmental Management Plans. Mitigation measures outlined in Chapter 14: Schedule of Mitigation

CEMD and site specific EMPs would be followed by contractors.

Extremely Unlikely

Disturbance of Otter and Water Vole

Buffers from watercourses, cover or use mammal ladders in excavations (construction)

CEMD and site specific EMPs would be followed by contractors.

Extremely Unlikely

Operation

N/A N/A N/A N/A


LT000022 8-1 Chapter 8:

Ornithology

8 ORNITHOLOGY

8.1 Introduction

8.1.1 This chapter considers the potential impacts on ornithological receptors from the construction and operation of the Proposed Development, as described in Chapter 2: Description of Development.

8.1.2 The objectives of the assessment were to: • identify sites designated for ornithological interests and habitats along the route

which are considered to be of conservation or ecological value to ornithological receptors;

• investigate the presence/possible presence of protected ornithological species and other species of particular conservation value;

• describe the likely potential impacts, including direct, indirect and secondary impacts as a result of the proposed works both during construction and once completed;

• calculate the probability of protected ornithological species and the implementation of predicted mortality on the integration of populations of protected species and international designations, colliding with the Proposed Development;

• describe the pre-construction mitigation measures that have been committed to in order to avoid or reduce impacts;

• describe the cumulative impacts when considering the Proposed Development alongside other schemes; and

• assess the significance of residual impacts that are likely to remain following implementation of mitigation and restoration measures.

8.1.3 This chapter, the impact assessment described within and the supporting technical appendices have been prepared and undertaken by Adam Fitchet BSc Hons MCIEEM and Espen Helland MSc ACIEEM both of Ramboll Environ UK Limited (ENVIRON). Field survey protocols were developed by NDR (Environmental Services) Ltd and ENVIRON and undertaken by local Caithness and Orkney field ornithologists working with ENVIRON and NDR (Environmental Services) Ltd.

8.2 Legislation and Policy Context International Legislation and Policy

Directive 2009/147/EC of the European Parliament on the Conservation of Wild Birds

8.2.1 This Directive1, known as the Birds Directive is the codified version of the original Directive 79/409/EEC, as amended. It provides a framework for the conservation and management of, and human interactions with, wild birds in Europe. It sets broad objectives for a wide range of activities, although the precise legal mechanisms are at the discretion of each Member State (in the UK delivery is via several different statutes). The identification and classification of Special Protection Areas (SPAs) for rare or vulnerable species, and for regularly occurring

1 http://ec.europa.eu/environment/nature/legislation/birdsdirective/index_en.htm

http://ec.europa.eu/environment/nature/legislation/birdsdirective/index_en.htm


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Chapter 8: Ornithology 8-2 LT000022

migratory species, are listed in Annex 1 of the Directive, paying particular attention to the protection of wetlands of international importance (Article 4). In Great Britain, the provisions of the Birds Directive are implemented through the Wildlife & Countryside Act 1981 (as amended).

The Ramsar Convention on Wetlands

8.2.2 The Convention on Wetlands2 is an intergovernmental treaty signed in Ramsar, Iran in 1971, which details the commitments of its member countries to maintain the ecological character of their Wetlands of International Importance and to plan for the sustainable use of all of the wetlands in their territories.


The Wildlife and Countryside Act 1981 (As Amended)

8.2.3 The Wildlife and Countryside Act (WCA) 19813 and its subsequent amendments is the principal mechanism for the legislative protection of the wildlife in Great Britain. The Act establishes a statutory framework for the protection of wildlife and also serves to implement the Birds Directive. The Act provides for the designation of Sites of Special Scientific Interest (SSSI), which are selected as the best national examples of habitat types, sites with notable species and sites of geological importance and protects all bird species from destruction of their nests when they are breeding. Schedule 1 of the Act details those ornithological species which receive additional protection from disturbance whilst breeding as well as protection from nest destruction.

Nature Conservation (Scotland) Act 2004

8.2.4 This Act4 places duties on public bodies in relation to the conservation of biodiversity, increases protection for SSSIs, amends legislation on Nature Conservation Orders, provides for Land Management Orders for SSSIs and associated land, and strengthens wildlife enforcement legislation. The Act places a duty on every public body to further the conservation of biodiversity consistent with the proper exercise of their functions.

Wildlife and Natural Environment Scotland Act 2011

8.2.5 This Act5 was introduced to make the law on wildlife and the natural environment more efficient, effective and proportionate. The main purposes of the Act are: to modernise deer management legislation and game law; introduce new rules on snaring; ensure badger licensing legislation is consistent with that of other species; control, contain and eradicate invasive non-native species; improve the administration of species licensing; abolish the Areas of Special Protection designation; increase flexibility in how muirburn6 is carried out; and improve SSSI legislation.


8.2.6 The Scottish Government published its Scottish Planning Policy (SPP)7 document in February 2010. It is concerned with the consolidation of a number of separate

2 http://www.ramsar.org/cda/en/ramsar-about-mission/main/ramsar/1-36-53_4000_0__ 3 http://www.legislation.gov.uk/ukpga/1981/69 4 http://www.legislation.gov.uk/asp/2004/6/contents 5 http://www.legislation.gov.uk/asp/2011/6/enacted 6 The practice of burning off old growth on a heather moor to encourage new growth for grazing. 7 http://www.scotland.gov.uk/Publications/2010/02/03132605/0

http://www.ramsar.org/cda/en/ramsar-about-mission/main/ramsar/1-36-53_4000_0__

http://www.legislation.gov.uk/ukpga/1981/69

http://www.legislation.gov.uk/asp/2004/6/contents

http://www.legislation.gov.uk/asp/2011/6/enacted

http://www.scotland.gov.uk/Publications/2010/02/03132605/0


LT000022 8-3 Chapter 8:

Ornithology

policies on issues such as sustainable development, community engagement and most pertinently for this chapter, the natural environment in to one concise policy document. The consolidation of the subject policies into the single SPP is not a review of established policy. Essentially, there is little change to the existing policy and the SPP makes clear that where possible, planning authorities should seek benefits for species and habitats from new development including the restoration of degraded habitats. It goes on to state that statutory natural heritage designations are important considerations where they are affected by a development proposal and the need for Appropriate Assessment of proposals potentially impacting SACs and SPAs is made clear. The level of protection given to local designations through the development plan should not be as high as the level of protection given to international or national designations.

UK Biodiversity Action Plan (UK BAP)

8.2.7 The UK BAP8, produced in 1994 by the Government, is a national strategy for the conservation of biodiversity. It is the UK Government's response to the Convention on Biological Diversity (CBD) signed in 1992. The Convention called for the development and enforcement of national strategies and associated action plans to identify, conserve and protect existing biological diversity, and to enhance it wherever possible. Action plans for the most threatened species and habitats have been set out to aid recovery, and achieve the significant reduction in biodiversity loss called for by the CBD.

Birds of Conservation Concern 3: The Population Status of Birds in the UK

8.2.8 The Royal Society for the Protection of Birds (RSPB) led a review, on a five year basis, of the population status of birds that occur in the UK9. Red list species are those that are either globally threatened10, showing rapid decline in recent years, or have declined historically and not shown a substantial recent recovery. Amber list species are those with an unfavourable conservation status in Europe, those showing moderate decline in recent years, those whose populations have declined historically but made a substantial recent recovery, rare breeders, or those with internationally important or localised populations. Species that fulfil none of the above criteria are green listed.

Regional and Local Policy

Highland Biodiversity Action Plan 2010-2013

8.2.9 The second edition of the Highland LBAP was published in 201011 by the Highland Council on behalf of the Highland Biodiversity Partnership which oversees progress and addresses some of the more strategic issues facing the Highlands’ nature and wildlife. The first Highland Biodiversity Action Plan (BAP) was produced in 2006; the second edition updates the Highland BAP and reprioritises work for the Partnership for the next three years.

8.2.10 The Highland Biodiversity Action Plan 2015-2020 is currently in its draft stage. It has been prepared by the Highland Environment Forum (HEF) and was due for launch in March 2015. It summarises the background and context of the plan as

8 http://jncc.defra.gov.uk/default.aspx?page=5155 9 Eaton M.A., Brown A.F., Noble D.G., Musgrove A.J., Hearn R.D., Aebischer N.J., Gibbons D.W. Evans A. and Gregory R.D.

(2009) Birds of Conservation Concern 3: The population status of birds in the United Kingdom, Channel Islands and the Isle of Man. British Birds 102: 296-341

10 According to International Union for the Conservation of Nature (IUCN) criteria. 11 http://www.highlandbiodiversity.com/pdf/Highland_Biodiversity_Action_Plan_2010-2013.pdf

http://jncc.defra.gov.uk/default.aspx?page=5155

http://www.highlandbiodiversity.com/pdf/Highland_Biodiversity_Action_Plan_2010-2013.pdf


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well as providing an update of the progress made since the biodiversity action plan process began in 2002. It also proposes new project ideas that could be undertaken to improve the biodiversity of Highland.

Caithness Biodiversity Action Plan

8.2.11 The Caithness Biodiversity Action Plan12 (Caithness BAP) was published in February 2003 and details the six key habitat groups within the Caithness area, the key species – both faunal and floral, found within them and the measures that can be adopted to enhance them.


8.3.1 Comments from consultees relevant to the ornithological assessment are listed in Table 8.1 below.



Scottish Natural Heritage (SNH)

Flight lines of bird species from the Caithness Lochs SPA show them crossing the preferred route. Particularly sensitive areas include the area between Lochend and Syster and Loch Durran. Whooper swans and Greenland greater white-fronted geese are very site faithful in these areas and present a collision risk. SNH recommend that their draft powerline collision risk model is also used to assess the collision risk resulting from this application.

Areas of high density Greenland greater white-fronted geese and whooper swan flights have been identified and collision risk has been considered higher at these local areas, and where necessary mitigation has been implemented. Additional Winter VPs were undertaken 2014-15 as agreed with SNH in November 2014. As agreed with SNH in May 2014 ENVIRON (Technical Appendix 8.1 Correspondence) will use the Collision Risk Assessment (CRA) that was developed by ENVIRON and used for the Dounreay – Mybster 275 / 132 kV Transmission Line (Appendix 8.2).

If hen harrier activity is recorded within 2km of the Caithness and Sutherland Peatlands SPA it should be assessed against the SPA breeding population.

Potential impacts on hen harrier populations are considered in section 8.8 Assessment of Residual Impacts.

If collisions are predicted for Caithness Lochs bird species then SNH modelling studies of Whooper swan and Greenland greater white-fronted goose (GWFG) populations should be used in the impact assessment.

SNH modelling studies have been included in the assessment and suitable mitigation such as line markers or undergrounding have been considered. CRAs for whooper swans have been assessed against SNH modelling studies in section 8.8 Assessment of Residual Impacts and section 8.9 Cumulative Effect.

12 http://www.highlandbiodiversity.com/htm/counties/caithness/caithness.pdf

http://www.highlandbiodiversity.com/htm/counties/caithness/caithness.pdf


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If impacts cannot be avoided through routeing wires should be marked at sensitive locations.

Line markers along the OHL in potentially sensitive areas would be implemented (see Mitigation During Operation OHL paragraph 8.7.17).

Cumulative impacts should be assessed with developments that are constructed, approved and at application stage. There are currently two wind farms near Loch Heilen for which consideration would have to be given.

Developments that are constructed, approved and at application stage have been assessed using SNH’s cumulative collision risk spreadsheet for Caithness and Sutherland in section 8.9 Cumulative Effects.

RSPB Scotland RSPB Scotland has specific concerns regarding the populations of wintering Greenland greater white-fronted goose and whooper swan, both of whose populations are in decline from the time of original designation and are under increasing pressure from renewable developments in the area. RSPB Scotland believe that sufficient mitigation options must be provided concerning minimising collision risk or timing of construction operations in bird sensitive areas.

Results of Caithness Lochs Surveys are detailed in section 8.5 Baseline Conditions as well as Caithness Lochs SPA species and other wildfowl species. Mitigation measures include avoidance of work in sensitive areas during winter months and line marking or undergrounding the cable at key goose and swan flight locations, as described in Section 8.7: Mitigation. CRA for whooper swans have been assessed against SNH modelling studies in section 8.8 Assessment of Residual Impacts and section 8.9 Cumulative Effect.

Consideration would have to be given to feeding/ loafing and flight areas of wintering geese and swans.

Pre-construction surveys would identify those areas in use and buffer zones would be established around the key fields and those sections of the LODs that fall within the buffer zones would be avoided. The GWFG Small Sites Study data has been taken into account to determine a baseline for feeding / loafing as described in section 8.5 Baseline Description.

Caithness Biodiversity Group

Concerns over collision risk of Caithness Lochs SPA birds and a request for consideration of measures such as bird deflectors/diverters on transmission lines within and between the known foraging and roosting areas of the wintering populations.

Mitigation measures as outlined in Section 8.7 include avoidance of work in sensitive areas during winter months and line marking and undergrounding at key goose and swan flight locations.


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Member of public Concerned that the preferred route crosses the path of migrating birds to Loch Heilen.

VP surveys with additional SPA Lochs surveys ensure that migrating birds to and from Loch Heilen are recorded and analysed using collision risk modelling. Additional VP surveys were conducted during the winter of 2014-15 and are reported in section 8.5 Baseline Conditions.


Study Area

8.4.1 The study area for this assessment can be seen on Figure 8.1. The viewsheds shown indicate the full extent of the study area covering the LOD of the Proposed Development. Where this has changed during the route selection process additional surveys have been undertaken to account for this. Loch Mey, Loch Heilen, Loch Scarmclate and Loch Watten were also surveyed for wildfowl.

Desk Study

8.4.2 A number of data sources were consulted for the desk study including: • Caithness Bird Report;

• SNH Caithness Lochs Survey Report13;

• Greenland Greater White-fronted Geese (GWFG) Small Sites Study – Final Report 201114;

• RSPB; and

• NBN Gateway.

Proposed Development Vantage Point Survey

8.4.3 A detailed survey scope and methodology was agreed with SNH in April 2011 ahead of the survey commencing15.

8.4.4 Vantage Point (VP) locations were identified from which flight activity of all target species within a two km corridor of the Proposed Development could be observed. VP locations were selected specifically: • to provide good views of the OHL LOD of the Proposed Development; and

• to observe direction of movement in relation to the Proposed Development.

8.4.5 VP locations and the visibility towards the LOD for the Proposed Development are shown on Figure 8.1.

13 http://www.snh.org.uk/pdfs/publications/commissioned_reports/523.pdf 14 Francis, I., Mitchell, C., Griffin, L. And Fox, T. 2011. Greenland White-fronted Geese: Land use and conservation at small

wintering sites in Scotland. http://greenlandwhitefront.org/publications/small-sites-report/ 15 ENVIRON (2011) RUK1216696_4_ Caithness reinforcements preliminary Ecological Appraisal

http://www.snh.org.uk/pdfs/publications/commissioned_reports/523.pdf


LT000022 8-7 Chapter 8:

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8.4.6 56 hours of observation were completed over a 12 month survey period at each VP location. Each VP watch was two hours long.

8.4.7 This survey specification allowed a constant survey effort throughout the year (allowing for the reduced amount of daylight hours during mid-winter). The effects of inclement winter weather resulted in the loss of a small proportion of this surveying time at some of the VPs although a total of 56 hours surveying time were completed for each VP. All flights along with weather data can be seen in Technical Appendix 8.3 and Technical Appendix 8.4.

8.4.8 One complete passage-winter-passage season (September 2011 – April / May 2012) and one complete summer breeding season (April / May 2012 - August 2012) were surveyed.

8.4.9 The full complement of VP watches was completed every fortnight and distributed as evenly as possible throughout all the available daylight hours through the various seasons.

8.4.10 Standard VP flight recording as set out in SNH best practice guidance was used. Height recording used height bands specific to each VP location. These bands were determined by the likely requirements of the proposed 132 kV OHL. Typically, three height bands were used: • below lowest wire height;

• wire spread; and

• above the highest wire.

8.4.11 Flight heights were recorded every 15 seconds for the duration of the flight or for five minutes, whichever was the greatest. If no other flight was observed, the observation continued to be mapped and recorded.

Additional Winter VP Surveys 2014-15

8.4.12 Due to the initial LOD alignment subsequently being refined during the consultation process, some areas along the LOD were not visible from the VPs during 2011-12 surveys. SNH also raised the need for a second season of winter survey data between Lochend and Syster, SNH correspondence from 3rd December 2014 shown in TA 8.1.

8.4.13 Four further VPs were chosen to be surveyed over winter 2014-15, to cover sections that were not covered during the 2011-12 surveys. The additional VPs were located at Achingills, Weydale, Loch Heilen and Syster Fields as shown on Figure 8.1.

8.4.14 Surveys commenced in November 2014 and concluded in April 2015. Each VP was surveyed three times each month for a total of three hours each time, giving a survey effort of 54 hours per VP. Surveys were spread out throughout the day with emphasis on dawn and dusk times.

8.4.15 Standard VP flight recording and methods were followed as described for the 2011-12 VP surveys.


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Caithness Lochs Vantage Point Survey

8.4.16 In order to record the flight activity of the qualifying species of the Caithness Lochs SPA to and from the component lochs of the SPA, all of which are SSSIs, a programme of VPs was completed separate to the Proposed Development VPs.

8.4.17 These surveys were supplementary to the above flight surveys to provide additional data about geese and swan movement around the designated sites during the passage seasons. The surveys targeted optimal times for this movement, i.e. dark and daylight hours around dawn and dusk.

8.4.18 Surveys were completed during the autumn passage period i.e. October - November 2011 and the spring passage period i.e. March – April 2012. This covered a full continuous winter period in two periods of nine weeks.

8.4.19 As for the locations for the Proposed Development VP survey, locations for the VP survey of the Caithness Lochs were selected to meet two main criteria: • provide good views of the SPA site to record movements to and from the site;

and

• observe direction of movement in relation to the Proposed Development.

8.4.20 VP locations were organised as follows: • one VP watching Loch of Mey;

• one VP watching Loch Heilen;

• one VP watching Loch Scarmclate; and

• one VP watching Loch Watten.

8.4.21 Typically three hours pre-dawn and three hours post-dawn were completed at a pair of VPs (e.g. Loch of Mey and Loch Heilen or Loch Scarmclate and Loch Watten) with dusk surveys completed the following week. This process was repeated with the VPs alternated for the following two weeks. Each watch lasted for a 3-hour period at dawn, dusk or the hours of darkness pre-dawn and post-dusk. This provided 27 hours additional survey time for each VP location per passage period.

8.4.22 Data was recorded using standardised forms to record flight information and height with the flight route recorded on a separate map. This information was then digitised into GIS for analysis.

Roaming Survey

8.4.23 The Proposed Development VP survey was completed fortnightly. In the alternate weeks, surveyors drove along the local road network surrounding the LODs for the Proposed Development to note the location of any feeding, loafing or roosting flocks of wild and waterfowl. This information was recorded on maps and then digitised into GIS for analysis.

Breeding Bird Survey

8.4.24 In order to record the numbers and distribution of breeding pairs/territories of bird species within the Proposed Development route corridors a breeding bird survey comprising three rounds of visits was completed between May and July 2012.


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8.4.25 In keeping with the British Trust for Ornithology (BTO) breeding bird survey methodology, surveyors walked sections of a transect route along the LODs of the Proposed Development and recorded the species, activity and behaviour of all birds and assigned each bird to one of three distance bands (0-25 m; 25-50 m; and 50-100 m).

8.4.26 The order in which the sections were surveyed was altered from visit to visit in order to ensure that all parts of the LOD for the Proposed Development were surveyed at all times of day.

8.4.27 Data was recorded on paper maps and then digitised into GIS. It was then analysed in GIS to combine the data from three visits into an overall map of territories for the LOD for the Proposed Development.

8.4.28 A species specific golden plover survey was considered, however activity by the species was not high enough to warrant such a survey.


Overview

8.4.29 The assessment has been completed according to the IEEM Guidelines (2006)16 and has comprised the following steps: • the baseline was defined, i.e. an assessment of the Proposed Development in

its current status, condition and ecological valuation was made;

• the potential development impacts (direct and indirect) and sources of impact on ornithological receptors were defined and quantified, where possible, in terms of magnitude, direction, extent, reversibility, likelihood and duration. Impacts resulting from the development were considered for both the construction, operational and decommissioning stages of the Proposed Development;

• consideration was given to mitigation and enhancement measures integral to the development proposals; and

• the significance of residual effects remaining after the mitigation and enhancement measures have been considered was assessed and, where considered appropriate, suitable additional mitigation measures described.

8.4.30 For the purpose of this assessment, ornithological receptors that have been considered within the assessment include designated sites, on-site and surrounding habitats, as well as on-site and surrounding species.

8.4.31 Mitigation refers to measures that are incorporated into the development proposals to proactively avoid, reduce, repair, reinstate, restore, 'rescue' and off-set adverse impacts.

8.4.32 Enhancement refers to measures that improve ecological and nature conservation (biodiversity) value but which are not measures specifically for the purposes of ecological mitigation.

16 IEEM. 2006. Guidelines for Ecological Impact Assessment in the United Kingdom.


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Collision Risk Model

8.4.33 The Collision Risk Model and subsequent CRA used for estimating collision risk to birds due to the OHL was developed by Ramboll Environ and agreed with SNH (Technical Appendix 8.1) to be used instead of the draft SNH collision risk model for powerlines (2014)17 which is still in development. Full details are given in Technical Appendix 8.2 along with a correction factor which was used for height adjustments as well as limitations and assumptions.

8.4.34 A basic collision risk model was developed utilising the principles of collision risk models developed for onshore wind farms18 as SNH does not recommend using the draft collision risk model currently in development19. The collision risk model applies the following stages of assessment: • definition of risk window;

• calculation of the number of birds at risk of collision, based on available survey data;

• extrapolation of survey data to provide an indication of annual flights, accounting for the seasonal nature of bird activity; and

• calculation of the probability of colliding with a wire, within the risk window.


8.4.35 Designated sites, habitats and species (i.e. ecological receptors) identified within the study area, see paragraph 8.4.1, have therefore been assigned ecological values using the standard CIEEM scale that classifies ecological and nature conservation receptors, including ornithological receptors. The following frame of reference has been used: • International Importance.

• National (UK) importance.

• Regional importance.

• County (metropolitan) importance.

• District (borough) importance.

• Local (parish) importance.

• Site Level importance (important within the Proposed Development and immediate environs).

• Negligible importance.

8.4.36 Table 8.2 gives examples of how the valuation of nature conservation features has been applied at different geographical scales and to different populations of species.

17 Estimating Bird Collision Risk with Power Lines. SNH. March 2014 (DRAFT). 18 Band, W., Madders, M., & Whitfield, D.P. 2007. Developing field and analytical methods to assess avian collision risk at wind

farms. In: de Lucas, M., Janss, G.F.E. & Ferrer, M. (eds.) Birds and Wind Farms: Risk Assessment and Mitigation, pp. 259- 275. Quercus, Madrid

19 Estimating Bird Collision Risk with Power Lines. SNH. March 2014 (DRAFT).


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Value Example

International Internationally designated sites including Special Protection Areas (SPA), , Ramsar site, potential SPAs and potential Ramsar sites; discrete areas which meet the published selection criteria for international designation but which are not themselves designated as such, or smaller areas which are essential to maintain the viability of a larger whole. Resident or regularly occurring populations of species which may be considered at an International / European level¹, the loss of which would adversely affect the conservation status or distribution of the species at an International / European level.

National Nationally designated sites including Sites of Special Scientific Interest (SSSI), National Nature Reserves (NNR), Marine Nature Reserve; discrete areas which meet the published selection criteria for national designation (e.g. SSSI selection guidelines) but which are not designated as such; or areas of a key habitat type identified in the UK Biodiversity Action Plan. Resident or regularly occurring populations of species which may be considered at the UK or National level², the loss of which would adversely affect the conservation status or distribution of the species across Britain or the Country.

Regional Areas of a key habitat type identified in the Regional BAP such as the Caithness BAP; viable areas of key habitat identified as being of Regional value in the appropriate Natural Heritage Zone (NHZ); or smaller areas of such habitat which are essential to maintain the viability of a larger whole. Resident or regularly occurring populations of species which may be considered at the Regional level, the loss of which would adversely affect the conservation status or distribution of the species across the Region.

County Designated sites at the county level including Sites of Nature Conservation Importance, County Wildlife Sites, Tree Preservation Orders; or discrete areas which meet the published selection criteria for county designation but which are not designated as such. Resident or regularly occurring populations of species which may be considered at the County level, the loss of which would adversely affect the conservation status or distribution of the species across the County.

District Designated sites at the local level including Local Nature Reserves (LNRs); or areas of habitat identified in a sub-county (district / borough) BAP. Resident or regularly occurring populations of species which may be considered at the District level, the loss of which would adversely affect the conservation status or distribution of the species across the District.

Local Features of local value include areas of habitat or populations / communities of species considered to appreciably enrich the habitat resource within the local context.


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Value Example

Site Areas of habitat considered to appreciably enrich the habitat resource within the Proposed Development. Includes viable populations of species which are of importance within the Proposed Development.

Negligible Areas of heavily urbanised or intensively managed land with negligible value to wildlife.

Notes: ¹: Species protected at a European level means: bird species listed within the Birds Directive. ²: Species protected or which may be considered at the UK or National level means: birds listed within Wildlife and Countryside Act 1981 (as amended) Schedule 1 and / or listed for their principal importance for biodiversity in accordance with the Nature Conservation (Scotland) Act 2004 Section 2(4); species listed within the UKBAP or UK Red Data Books.

8.4.37 The sensitivity of an ecological receptor is defined as its susceptibility to being affected by an impact. Receptors are considered to be of high, moderate or low sensitivity.

Impact Characterisation

8.4.38 In order to characterise the impacts on each feature, the parameters set out in Table 8.3 have been considered.



Direction Impacts are either adverse (negative) or beneficial (positive).

Magnitude The size or amount of an impact, determined on a quantitative basis where possible, e.g. “partial” or “total” loss of an area of habitat or number of individuals affected. Where exact amounts are unquantifiable, this is defined simply as high, moderate or low.

Extent The area over which an impact occurs.

Duration The time for which the impact is expected to last prior to recovery of the receptor or replacement of the receptor by similar resource (in terms of quality and / or quantity). This is expressed as a short term, medium term, or long term effect relative to the ornithological feature that is impacted.

Reversibility Irreversible impacts: permanent changes from which recovery is not possible within a reasonable time scale or for which there is no reasonable chance of action being taken to reverse it. Reversible impact: temporary changes in which spontaneous recovery is possible or for which effective mitigation (avoidance / cancellation / reduction of effect) or compensation (offset / recompense / offer benefit) is possible.

Likelihood of Impact The likelihood of an impact occurring. The following convention, adapted from the Intergovernmental Panel on Climate Change (IPCC), is adopted: • Virtually certain > 99% probability of occurrence


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Parameter Description • Extremely likely 96 - 99% • Very likely 91 - 95% • Likely 67 - 90% • More likely than not 51 - 66% • Possible 34 - 50% • Unlikely 11 - 33% • Very unlikely 6 - 10% • Extremely unlikely < 5%

Significance

8.4.39 An assessment is then made of whether an impact acting on an ornithological receptor could result in an effect which would be ecologically significant, based on the outcome of the receptor evaluation and impact characterisation.

8.4.40 In this assessment an ecologically significant impact is defined following IEEM (2006), as resulting from "an impact (beneficial or adverse) on the integrity of a defined site or ecosystem and / or the conservation status of habitats or species within a defined geographical area." The determination of ecological significance is based on professional judgement. In addition, the value of the receptor defines the geographical terms of reference at which a predicted impact may result in a significant impact. Where an impact of at least moderate magnitude and a likelihood of occurrence of possible (34 - 50%) or greater is identified on a receptor of greater than county level value, this is considered to result in an ecologically significant impact.

8.4.41 Where an ecologically significant impact is identified this is also considered to be a significant impact in EIA terms.

8.4.42 For clarity, it is noted that some potential impacts are not considered significant in EIA terms. Where such impacts are identified no specific mitigation is required, however good practice would be to control these impacts as far as practicable.

Designated Sites

8.4.43 The Proposed Development is not located within areas of designated importance for birds (e.g. SSSIs and SPAs) (Figure 8.2). However, the Caithness Lochs SPA, the North Caithness Cliffs SPA and part of the Caithness and Sutherland Peatlands SPA are located 400 m, 4,000 m and 3,300 m respectively from the Proposed Development at their closest points and many of the bird species from those SPAs use the habitats in the vicinity of the Proposed Development. Potential impacts on the Qualifying Interest species of the SPAs are considered within this chapter.

8.4.44 Birds from outwith the designated sites also use the area of the Proposed Development. In view of this, the magnitude of likely impacts on the wider countryside ornithological interest is assessed, as set out by SNH (200620)

20 Scottish Natural Heritage. 2006. Assessing significance of impacts from onshore wind farms on birds outwith designated

areas.


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guidance ‘Assessing significance of impacts from onshore wind farms on birds outwith designated areas’.

8.4.45 The idea of ‘Favourable Conservation Status’ (FCS) as described in the Habitats Directive is not described in the Birds Directive, but best practice advocates its use in making assessments of impacts on bird species. The conservation status of a bird species is considered favourable where: • the species is maintaining itself on a long-term basis as a viable component of

its habitat;

• the natural range of the species is not being reduced, nor is the species likely to be reduced in the foreseeable future; and

• there is currently and for the foreseeable future, a large enough habitat area to maintain the species’ populations on a long-term basis.

8.4.46 According to SNH (2006)21, an impact should be judged as being of concern where it would affect the FCS of a species, or stop a recovering species from reaching FCS, at either international, national or regional population levels. However, with the exception of hen harrier Circus cyaneus, the existing conservation status of the species considered in this assessment are not defined by SNH. Therefore, to allow an assessment of potential impacts against the FCS of a species, the baseline status first needs to be established so that the effects of any impacts from the Proposed Development can be assessed. This is completed in this assessment using the three factors set out previously.

Limitations to the assessment

8.4.47 Where assumptions within the ornithological assessment have been made, these are identified and explained. Similarly, limitations in methods are identified and discussed, particularly where this is likely to affect the outcome of the assessments. As with any environmental assessment there will be elements of uncertainty. Where relevant, these are identified and reported, together with a statement on any implications on the assessment and conclusions.

8.4.48 Due to the fact that VP surveys commenced and concluded before the LOD of the Proposed Development was agreed upon, some of the areas along the Proposed Development now lie outwith the area that the surveys covered. However, this was addressed by the completion of a full additional winter VP survey in 2014-15 at four new VP locations in those sections of the LOD where it deviated from the LOD as surveyed in 2011/2012.

8.4.49 Bird surveys are based on sampling techniques, not absolute censi. Results give an indication of numbers and activities of birds at the particular times that surveys were carried out. The surveys for the Proposed Development were distributed by time of day and by date throughout the year sufficient to give a representation of the range of activity, but were limited occasionally by inclement winter weather, though this did not compromise the overall survey effort. The full scope of the surveys was discussed and agreed with SNH in advance of commencement. No gaps were identified in the baseline data that would prevent assessments being

21 Ib id


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undertaken for the purposes of determining likely significant impacts as is required by the EIA Regulations22.

8.4.50 Due to the fact that the breeding bird survey was conducted prior to some changes to the Proposed Development, some of the records fall outwith the current LOD. However, the surrounding habitat where the surveys were undertaken consists of similar habitat to that within the LOD, and therefore serves as a good indication of the types of bird species and their relative abundances that are present within the current LOD and it is believed that an accurate baseline of the species present and potentially impacted has been collected.


8.5.1 The following paragraphs set out the current designated sites in the vicinity of the Proposed Development and in the wider area as well as the populations of all bird species recorded both within the vicinity of the Proposed Development and at the designated sites.

8.5.2 The farmland and peatland dominated habitats of the Proposed Development and the waterbodies in the wider area support important wildfowl populations particularly in the non-breeding, winter period. As well as the designated sites themselves, the wildfowl populations utilise the vicinity of the Proposed Development for a variety of activities including feeding and loafing. Their flightlines also cross the LOD for the Proposed Development. More distant designated peatland habitats support important breeding populations of waterfowl, waders and raptors which again occasionally use the area around the Proposed Development or at least fly over it. In addition, there are bird species not associated with any designated sites which use the habitats in the vicinity of the Proposed Development both during the winter non-breeding period and summer breeding periods.

Future Baseline

8.5.3 The overall baseline of the ornithological fauna in the vicinity is considered to remain similarly dominated by non-breeding winter wildfowl and breeding waders, raptors and wildfowl. Current trends in the populations of particular species suggest that some may be found in lower numbers than the current baseline and conversely some may be found in higher numbers than at present. However, the overall suite of species is likely to remain similar as long as the habitats currently supporting them remain similar. As the key areas for many of these species are designated sites, they are considered to remain in their current condition.

Nature Conservation Designations

8.5.4 Three Special Protection Areas (SPAs) designated for their internationally important ornithological interests lie in the vicinity of the Proposed Development (Figure 8.2). They are listed here in order of potential relevance to the Proposed Development, with the species listed as per the relevant SPA citation.

22 Notwithstanding this, the indications from the surveyors, who were all local to the area of the Proposed Development and

understand the bird activity of that area, summer 2012 was considered to be a poor breeding season for many species and indicate that the records gathered reflect that suggestion.


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Caithness Lochs SPA, Ramsar Site

8.5.5 This SPA, comprising six shallow, eutrophic lochs and one wetland area was designated in 1998. Each component loch/site is also a SSSI as listed at paragraph 8.4.11. The SSSIs and subsequent SPA were designated for regularly supporting wintering populations of international importance23 of: • Greenland greater white-fronted goose Anser albifrons flavirostris (440 birds);

• (Icelandic) Greylag goose Anser anser (7,190 birds); and

• (Icelandic) Whooper swan Cygnus cygnus (240 birds).

8.5.6 At the closest point (east of Castletown) this SPA lies approximately 400 m from the undergrounding section of the Proposed Development and 1,500 m from the OHL of the Proposed Development.

8.5.7 Data from SNH (2009)24 which is used in the assessment of cumulative collision risk in the region, indicates that the current Caithness Lochs SPA qualifying interest's populations are now: • 338 Greenland greater white-fronted geese (23% decrease in 11 years);

• 9,105 greylag geese (21% increase in 11 years); and

• 208 whooper swans (13% decrease in 11 years).

8.5.8 Most recent data detailing a count of Greenland greater white-fronted geese was completed as part of the GWFG Small Sites Study in 2011. As described later in this assessment, two distinct populations of the subspecies use the Caithness area each winter; the Westfield population; and the Loch of Mey population. A count in March 2011 recorded 135 birds in the Westfield population and 118 in the Loch of Mey population. This is a total of 253 birds and would indicate a decrease of 42.5% in the 13 years since 1998.

8.5.9 The component lochs of the SPA also form the Caithness Lochs Ramsar site. The site was designated in 1998 as the lochs include a range of conditions from oligotrophic to eutrophic which support a wide diversity of aquatic and wetland plant species including submerged and floating aquatic communities and species-rich marginal, fen and swamp communities that support internationally important overwintering populations of the species listed above.

8.5.10 The Conservation Objectives for the Caithness Lochs SPA (SNH, 2011) are: • 'To avoid deterioration of the qualifying habitats of the qualifying species or

significant disturbance to the qualifying species, thus ensuring that the integrity of the site is maintained'; and

• 'To ensure for the qualifying species that the following are maintained in the long term:

− Population of the species as a viable component of the site;

− Distribution of the species within site;

− Distribution and extent of habitats supporting the species;

23 five year peak means for 1993/94 to 1997/98 24 Scottish Natural Heritage. 2012. Cumulative Assessment spreadsheet for wind farms – Caithness and Sutherland.


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− Structure, function and supporting processes of habitats supporting the species; and

− No significant disturbance of the species'.

8.5.11 The Five-Year Implementation Plan 2007-2012 for Greenland White-fronted goose sets out a clear objective to: • ‘Ensure the protection and management of all internationally important

wintering and passage sites in NW Europe, with particular reference to satellite populations, the loss of which would contribute significant range contractions.’

8.5.12 The Caithness populations are satellite populations as described and so maintenance of the species range in Caithness is a key consideration.

Caithness and Sutherland Peatlands SPA

8.5.13 This large and extensive SPA includes peatlands across Caithness and Sutherland. It was designated in 1999 for supporting breeding populations of international importance of: • Golden eagle Aquila chrysaetos (five pairs25);

• Short-eared owl Asio flammeus (30 pairs26);

• Hen harrier (14 pairs27);

• Merlin Falco columbarius (54 pairs28);

• Black-throated diver Gavia arctica (26 pairs29);

• Red-throated diver Gavia stellata (89 pairs30);

• Golden plover Pluvialis apricaria (1,064 pairs31);

• Wood sandpiper Tringa glareola (less than five pairs32);

• Dunlin Calidris alpina schinzii (1,860 pairs33);

• Common Scoter Melanitta nigra (27 pairs);

• Greenshank Tringa nebularia (256 pairs); and

• Wigeon Anas penelope (43 pairs).

8.5.14 More recent data from SNH (2009)34 indicates that the Caithness and Sutherland Peatlands SPA qualifying interest's populations are now: • 5 golden eagle pairs (no change);

• 30 short-eared owl pairs (no change);

• 9 pairs of hen harrier (35% decrease in 12 years);

• 54 pairs of merlin (no change);

25 Count, as at 1992 26 Count, as at mid-1990s 27 Five year mean, 1993-1997 28 Count, as at early 1990s 29 11 year mean, 1986-1996 30 Two year mean, 1993-1994 31 Count, as at mid-1990s 32 Two year mean, 1994-1995 33 Count, as at 1994 34 Scottish Natural Heritage. 2012. Cumulative Assessment spreadsheet for wind farms – Caithness and Sutherland.


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• 26 black-throated diver pairs (no change);

• 39 red-throated diver pairs (56% decrease in 15 years);

• 1,064 pairs of golden plover (no change);

• 3 pairs of wood sandpiper (less than 40% decrease in 14 years);

• 1,860 pairs of dunlin (no change);

• 37 pairs of common scoter (37% increase);

• 256 pairs of greenshank (no change); and

• 43 pairs of wigeon (no change).

8.5.15 At the closest point, this SPA lies approximately 3,300 m from the Proposed Development.

8.5.16 The component SSSIs of the SPA in the vicinity of the Proposed Development are detailed in the following paragraphs.

8.5.17 Stroupster Peatlands SSSI was notified in its current size and format in 1985 after part of it was previously notified as Lochs of Auckengill in 1981. The site is measured at 2,813 ha and supports red-throated diver, black-throated diver, common scoter, dunlin, golden eagle, golden plover, greenshank, hen harrier, merlin, short-eared owl, wigeon and wood sandpiper.

8.5.18 The component peatlands of the SPA also form the Caithness and Sutherland Peatlands Ramsar site. The Ramsar site was designated in 1999 as the peatlands represent one of the largest and most intact areas of blanket bog in the world which supports an internationally important breeding population of dunlin and ten nationally important breeding waterfowl populations.

8.5.19 The Conservation Objectives for the Caithness and Sutherland Peatlands SPA (SNH, 2011) are: • 'To avoid deterioration of the qualifying habitats of the qualifying species or

significant disturbance to the qualifying species, thus ensuring that the integrity of the site is maintained'; and

• 'To ensure for the qualifying species that the following are maintained in the long term:

− Population of the species as a viable component of the site;

− Distribution of the species within site;

− Distribution and extent of habitats supporting the species;

− Structure, function and supporting processes of habitats supporting the species; and

− No significant disturbance of the species'.

North Caithness Cliffs SPA

8.5.20 This SPA was designated in 1996 for its internationally important breeding population of the following cliff nesting species: • Razorbill Alca torda (4,000 birds);

• Peregrine Falco peregrinus (6 pairs);


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• Atlantic puffin Fratercula arctica (1,750 pairs);

• Northern fulmar Fulmarus glacialis (14,700 pairs);

• Black-legged kittiwake Rissa tridactyla (13,100 pairs); and

• Common guillemot Uria aalge (38,300 birds).

8.5.21 Updated information on the population sizes of these species is not included in the SNH 2009 Cumulative Collision Risk Spreadsheet and not publically available.

8.5.22 Dunnet Head SSSI was notified in its current size and format in 1985 after being notified as three separate sites in 1949; Easter Head to Little Score SSSI, Dunnet Head SSSI and part of Point of Ness to Chapel Geo SSSI. The site is designated for the nationally important coastal vegetation and breeding seabirds including: fulmar, guillemot, kittiwake, peregrine, puffin and razorbill.

8.5.23 At the closest point at Dunnet Bay this SPA lies approximately 4,000 m the Proposed Development.

8.5.24 The Conservation Objectives for the North Caithness Cliffs SPA are: • 'To maintain the size and distribution of the populations of breeding seabirds

and to avoid significant disturbance to these birds during the breeding season'; and

• 'To maintain the size and distribution of the populations of breeding peregrine and to avoid significant disturbance to these birds during the breeding season' by working with land managers to protect the site and for SNH to carry out survey, monitoring and research as appropriate to increase knowledge of the site.

Species Descriptions

8.5.25 Behavioural sensitivity and FCS have been assessed for SPA species only.

Caithness Lochs SPA Species

GREATER WHITE-FRONTED GOOSE

8.5.26 Approximately 16,000 Greenland greater white-fronted geese overwinter in Scotland, comprising approximately 65% of the world population of this subspecies35. European greater white-fronted geese Anser albifrons also occur although in far lower numbers36. The distinction between the two subspecies was not always possible during the surveys and as such all greater white-fronted goose records have been treated as Greenland greater white-fronted geese.

8.5.27 As described in paragraph 8.5.7, the GWFG Small Sites Study identified and characterised two distinct population of this subspecies visiting Caithness each winter: the Westfield population; and the Loch of Mey population37. Together these two populations make up the overall SPA population of this subspecies. The flock recorded around the Proposed Development is the "Loch of Mey / Loch Heilen" flock based in that area of Caithness approximately 400 m to the northwest of the undergrounding section of the Proposed Development. The flock of geese recorded at Loch Watten is considered more likely to be birds from that flock, as

35 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady. 36 Ib id. 37 http://greenlandwhitefront.org/gb-site-inventory/


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historically there was a third flock in the vicinity of Lochs Scarmclate and Watten which mingled with the Loch of Mey / Loch Heilen flock, but as the Greenland greater white-fronted goose population declined, this became a single flock recorded in the vicinity of Loch of Mey/Loch Heilen and only occasionally around Lochs Scarmclate and Watten. It appears that there is little movement between the two flocks during the winter.

8.5.28 Based on the data from the GWFG Small Sites Study, the Loch of Mey population has shown an overall slow decline in count numbers over the 10 year period between 1999 and 200938 and is considered to be at moderate risk of extinction39.

8.5.29 The GWFG Small Sites Study data38 suggests that the productivity of the population has decreased since 1990 with the percentage of young recorded decreasing from over 20% to less than 10%. Annual adult survival does not appear to be declining. However, with apparently decreasing recruitment into the population, the declining population trend will continue and potentially at an increasing rate as remaining individuals age. Recent survey work in Greenland suggests that a combination of factors may have led to declining productivity including poor early spring weather or competition with Canada geese Branta canadensis interior for food or nest locations40.

8.5.30 VP watch data shows that the species was recorded occasionally in the vicinity of Philips Mains farm where the proposed substation is to be located. Birds were recorded throughout the autumn / winter period with the first record on 28th October 2011 and the last on 8th January 2012. A total of seven flights were recorded with a maximum flock size of 100 birds (Figure 8.3).

8.5.31 During the additional winter VP surveys this species was recorded 19 times, all in the area approximately one km east of Loch Heilen. The largest flight flock consisted of 43 individual birds, the species was also observed using the fields adjacent to the small conifer plantation by the Syster Fields VP to feed where they were recorded in numbers of 91, 100 and 101 individuals respectively, (Figure 8.4).

8.5.32 The species was recorded regularly during the Caithness Lochs Survey. At Loch of Mey a total of 14 flights were recorded between 4th November 2011 and 31st March 2012 with a peak of 180 birds in a single flock as shown on Figure 8.5a. At Loch Heilen which is closest loch to the Proposed Development, two flights were recorded of one and 80 birds (Figure 8.5b). A single flight of 10 birds were recorded at Loch Watten in March 2012 (Figure 8.5c). The species was recorded in all months of the survey with peak activity in November 2011 and February/March 2012. Birds were recorded flying north-west towards Loch of Mey and south-east towards Phillips Mains at the north-eastern end of the Proposed Development (Figure 8.5a).

8.5.33 The species was not recorded during the roaming survey.

38 A comparison of the combined count numbers from the Westfield population and the Loch of Mey population against the

overall SPA count at designation indicates a decline of approximately 40%. It is important to note however that the count numbers on which the SPA was designated and the count numbers for the GWFG Small Sites Study are not directly comparable due to differences in the survey methodologies used to gather the data. The initial SPA data is based upon 5 year means. The GWFG Small Sites Study data is based on single visit point counts. As a result the % rates of decline quoted here are approximations only.

39 Francis, I., Mitchell, C., Griffin, L. And Fox, T. 2011. Greenland White-fronted Geese: Land use and conservation at small wintering sites in Scotland. http://greenlandwhitefront.org/publications/small-sites-report/

40 Mitchell, C. et al (2011) Greenland White-fronted geese: Investigating causes of low reproductive output in Greenland – report to SNH.


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8.5.34 There is limited literature examining disturbance of goose species associated with the presence of OHLs. Greenland greater white-fronted geese typically inhabit areas where the species already comes into contact with existing OHLs and human activity41, including activity associated with OHLs that might disturb them from their feeding and roosting areas. Notwithstanding, geese return to these areas throughout the winter and in subsequent years. Given this, the species is considered to be of moderate behavioural sensitivity.

8.5.35 The marked decline in the population of Greenland greater white-fronted geese recorded at the Caithness Lochs means that in terms of the first test of favourable conservation status, the species may not be maintaining itself on a long-term basis as a viable component of its habitat and for the purposes of this assessment, the SPA population is considered to have an unfavourable conservation status.

GREYLAG GOOSE

8.5.36 Approximately 110,000 greylag geese overwinter in Scotland. This includes both migratory birds and resident birds. Over 95% of the Icelandic greylag goose population overwinters in Scotland42.

8.5.37 This species was recorded frequently along the length of the Proposed Development throughout the autumn / winter period with occasional flights occurring during the summer breeding period. A total of 97 flights (Figure 8.6) were recorded with a maximum flock size of 450 birds.

8.5.38 A total of 76 flights of greylag goose were recorded during the additional winter surveys (Figure 8.7). The largest flocks consisted of 350, 250 and 220 individual birds and were all recorded at the eastern end of the Proposed Development to the south of Weydale. The largest flock recorded near Loch Heilen consisted of 180 individual birds and was observed near the Proposed Development, flying north-west towards Loch Heilen.

8.5.39 The species was also recorded frequently during the Caithness Lochs Survey. Closest to the Proposed Development 19 flights were recorded at Loch of Mey (Figure 8.8a) with the largest flock consisting of 500 individuals, and 29 flights at Loch Heilen (Figure 8.8b). A total of 147 flights were recorded at Lochs Scarmclate and Watten (Figure 8.8c). Flights to and from Loch Scarmclate and Loch Watten appear to have a north-south orientation with the birds from Loch Scarmclate possibly approaching the Proposed Development at Durran. The flights that have been recorded at Loch Heilen appear to fly north and northwest and therefore do not cross the Proposed Development. Many of the flights recorded at Loch of Mey originate southeast of the loch in the direction of the Proposed Development at Philips Mains as seen in Figure 8.8a.

8.5.40 The species was recorded frequently during the fortnightly roaming survey around the area of Durran (Figure 8.9). The highest concentrations were recorded north of the Proposed Development at Wester Olrig with the largest flock consisting of 2,000 individuals. Four observations were made near Loch Heilen with numbers ranging from just a few individuals to 300 birds. Greylag geese were recorded during the roaming survey as most active during the months of October 2011 to

41 per observations 42 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady.


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February 2012. The species was recorded in similarly widespread locations by observers completing survey work for the SNH report into the Caithness Lochs43.

8.5.41 There is a small resident greylag goose population in Caithness and Sutherland that remains in the area year round. It has not been possible to distinguish birds from the resident population from the overwintering population and so all flights by the species have been considered to be part of the Caithness Lochs SPA population. However, the lack of greylag goose activity across the Proposed Development between April and August indicates that the resident greylag goose population does not use the area of the Proposed Development during the summer months and from the available SSSI information, it appears that they breed to the south of the Proposed Development in the component SSSIs of the Caithness and Sutherland Peatlands SPA.

8.5.42 Like the Greenland greater white-fronted geese, the greylag geese typically inhabit areas, where they come into contact with non-natural structures which already present a potential collision risk and human activity that disturbs them from their feeding and roosting and areas. Nevertheless, they return to these areas throughout the winter and in subsequent years. Given this combination of some disturbance from human activities but continued usage of areas near human activity, the species is considered to be of moderate behavioural sensitivity.

8.5.43 Due to the significant increase in the number of greylag geese recorded at the Caithness Lochs, the species is considered to be maintaining itself on a long term basis as a viable component of the habitat and is considered to have favourable conservation status.

WHOOPER SWAN

8.5.44 Approximately 4,000 whooper swans overwinter in Scotland. This represents around 15% of the Icelandic population44.

8.5.45 The species was recorded frequently along the length of the Proposed Development throughout the autumn/winter period of VP surveys with the first record on 12th October 2011 and the last on 15th March 2012. A total of 51 flights were recorded with a maximum flock size of 40 birds (Figure 8.10). The area of Philips Mains had a high activity of this species with 15 recorded flights. Other high activity areas along the Proposed Development for this species were at Lochend, to the south of Loch Heilen with 14 flights recorded and Durran which had a total of 16 flights.

8.5.46 A total of 26 flights were recorded during the additional winter surveys (Figure 8.11). Only two flights were recorded near Weydale consisting of three and 11 birds respectively. The majority of the whooper swan flights were recorded near or crossing the LOD of the Proposed Development at Lochend with the largest flocks consisting of nine and 22 individual birds.

8.5.47 The species was also recorded frequently during the Caithness Loch Survey. Close to the Proposed Development, 30 flights were recorded at Loch of Mey (Figure 8.12a) and 29 flights at Loch Heilen (Figure 8.12b). A total of 35 flights were recorded at Lochs Scarmclate and Watten (Figure 8.12c). Flights at Loch Scarmclate show a slight directional trend towards the north-west of the loch

43 http://www.snh.org.uk/pdfs/publications/commissioned_reports/523.pdf 44 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady.


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towards the Proposed Development (Figure 8.12c). Flights at Loch of Mey are mostly oriented in a west and south-westerly direction with a smaller proportion flying in a southeast direction towards the Proposed Development at Philips Mains. Flights at Loch Heilen include flights oriented towards the west, with other flights in no particular directional pattern but only few flights observed towards the Proposed Development at Lochend.

8.5.48 The species was observed occasionally during the roaming surveys, with most frequent records made near Loch Heilen at Lochend, where seven flocks were recorded at counts of one to 54 individuals (Figure 8.13). Flocks of this species were also recorded near Durran with eight observations made with counts ranging from two to 60 individuals. The largest flock consisted of 200 whooper swans and was recorded at West Greenland approximately 1.5 km from the Proposed Development at Bowermadden.

8.5.49 The whooper swans inhabit similar areas and habitats as the two previously discussed goose species and given this combination of some disturbance from human activities but continued usage of areas near human activity has an equally moderate behavioural sensitivity.

8.5.50 As described for the Greenland greater white-fronted geese, the decrease in the number of whooper swans recorded at the Caithness Lochs means that the species is not considered to be maintaining itself on a long term basis as a viable component of its habitat and is therefore considered to have unfavourable conservation status for the purposes of this assessment.

Caithness and Sutherland Peatlands SPA Species

GOLDEN EAGLE

8.5.51 No flights by this species were recorded either during the VP survey or Caithness Lochs survey and no records were made during the roaming survey.

SHORT-EARED OWL

8.5.52 Up to 1,250 pairs of short-eared owls breed in Scotland each year which is 77% of the British breeding population. Numbers increase to as many as 3,000 birds during the winter with the influx of potentially hundreds of migratory birds. Numbers are however extremely variable from year to year45.

8.5.53 No flights by this species were recorded during the VP surveys or additional VP surveys.

8.5.54 Two flights of this species were recorded during the Caithness Lochs survey at Loch of Mey approximately one km northwest of the Proposed Development on 31st March 2012 and 14th April 2012 as seen in Figure 8.14.

8.5.55 Short-eared owls typically hunt and nest in peatlands some distance from areas of high human activity and consequent disturbance. The species is considered to have high behavioural sensitivity to disturbance by virtue of the typically isolated locations that it inhabits.

8.5.56 The population of this species within the SPA is stable and the species is maintaining itself on a long term basis as a viable component of its habitat. Also,

45 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady.


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the natural range of the species and the available habitat area for the species are not altered and as such the conservation status of the species is considered to be favourable.

HEN HARRIER

8.5.57 More than 600 breeding pairs of hen harrier occur in Scotland with a comparable number of birds present in the winter46.

8.5.58 Hen harriers are present on breeding territories in the Highlands from April-September, after which they usually migrate to winter in lowland areas. This species was recorded occasionally along the Proposed Development throughout the year. A total of 52 flights were recorded along the full length of the Proposed Development (Figure 8.15) with nearly half of those flights (25) concentrated along the length of the Proposed Development between Moss of Greenland and Lochend, where some activity were recorded in summer as well as through the winter months, suggesting that the species might be nesting in the wider peatland habitats beyond the Proposed Development. Activity along the Proposed Development was highest during the winter months indicating that the area is used more by the species during the non-breeding period when harriers typically move further from their breeding territories to find food (Figure 8.15).

8.5.59 During the additional winter surveys, a total of 31 hen harrier flights were recorded, as shown on Figure 8.16. A single flight crossed the LOD by South Weydale, with five flights recorded just north of the LOD in the same location. Four flights were recorded around Achingills with none of these crossing the LOD. The rest of the flights, 21, were recorded at Lochend with eight of these crossing the LOD of the Proposed Development.

8.5.60 11 of these flights were recorded on a single evening on the 19th November 2015, with these flights involving at least five separate birds. This high level of activity around dusk indicates a likely communal roost nearby. Hen harriers use communal roosts in winter with these usually found in scrub or woodland. There are potential roost sites to the east of Lochend and, while such high activity levels were not recorded again during the additional survey period, the presence of a temporary communal roost is considered likely.

8.5.61 Four hen harrier flights, all of a single bird, were recorded during the Caithness Lochs survey with two flights at Loch of Mey on 18th November 2011 (Figure 8.17a). One flight recorded at Loch Scarmclate on 1st March 2012 and one at Loch Watten on 22nd February 2012 as seen in Figure 8.17b.

8.5.62 This species was recorded three times during the roaming survey. All three observations were made Near Mayfield as seen in Figure 8.18, with the record closest to the Proposed Development approximately 1 km north of the 132 kV OHL.

8.5.63 Like short-eared owls, hen harriers typically inhabit peatland habitats away from human habitations and activity. Expert opinion47 suggests safe working distances of 500-750 m for breeding hen harriers and the species is considered to have high behavioural sensitivity to disturbance.

46 Ib id 47 Ruddock, M. and Whitfield, D.P. 2007. A review of disturbance distances in selected bird species. A report from Natural

Research (Projects) Ltd to SNH.


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8.5.64 The population of this species within the SPA has increased and as such the conservation status of the species is considered to be favourable.

MERLIN

8.5.65 Approximately 800 pairs of merlin breed in Scotland with as many as twice that recorded during the winter48.

8.5.66 Merlins are usually present on breeding territories in the Highlands from March-September, after which they migrate to winter in lowland and coastal areas. The species was recorded infrequently along the Proposed Development throughout the year. A total of 10 flights, all of single birds, were recorded throughout the year of VP surveys (Figure 8.19).

8.5.67 A total of 13 merlin flights were recorded during the additional winter (Figure 8.20). The majority of flights were recorded by South Weydale, with only a single flight crossing the Proposed Development west of Fryster.

8.5.68 Two flights were recorded during the Caithness Lochs survey with two flights of one bird each on 22nd March and 19th April 2012 at Loch of Mey (Figure 8.21).

8.5.69 This species was not recorded during the roaming survey.

8.5.70 Breeding merlin are sensitive to human activity, visual disturbance and sudden noise events over distances of up to 500 m. However, some individual merlins appear to tolerate moderate levels of disturbance in some situations49. This species is therefore considered to have moderate-high behavioural sensitivity.

8.5.71 The population of this species within the SPA is stable and as such maintaining itself on a long-term basis as a viable component of its habitat and as such the conservation status of the species is considered to be favourable.

BLACK THROATED DIVER

8.5.72 No flights by this species were recorded either during the VP survey, additional VP survey or Caithness Lochs survey and no records were made during the roaming survey.

RED THROATED DIVER


GOLDEN PLOVER

8.5.74 The Scottish golden plover breeding population is approximately 15,000 pairs increasing to as many as 35,000 birds when overwintering flocks come to Scotland.

8.5.75 Golden plover are usually present on their breeding grounds in the Highlands between mid-March and August. This species was recorded frequently along the length of the Proposed Development throughout the year with the first record on 18th August 2011 and the last on 29th August 2012 (Figure 8.22). A total of 54

48 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady. 49 Ruddock, M. and Whitfield, D.P. 2007. A review of disturbance distances in selected bird species. A report from Natural

Research (Projects) Ltd to SNH.


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flights were recorded with the largest flock size being 450 birds seen on close to Hilliclay where most of the observations of this species were made.

8.5.76 A total of nine golden plover flights were recorded during the additional winter surveys (Figure 8.23). A flock of 40 birds crossed the Proposed Development near South Weydale in April 2015, with another two flights crossing the LOD near Lochend of 80 and 22 birds respectively.

8.5.77 No records of this species were made during the Caithness Lochs survey.

8.5.78 This species was recorded occasionally during the roaming survey with a total of 10 separate observations (Figure 8.24). The largest flock was recorded at Hilliclay, with 400 individuals on 20th October 2011. Most records of golden plover were made during October in 2011.

8.5.79 Golden plover are potentially vulnerable to collision with power lines when displaying, mobbing avian intruders, or commuting between breeding and feeding areas. They are typically low flying and have relatively small territories making them less vulnerable to collision than high flying waders with large territories. When breeding, this species is sensitive to human activity, visual disturbance and sudden noise events over moderate distances of up to 250 m and so is considered to have a moderate behavioural sensitivity.

8.5.80 The population of this species within the SPA is stable and as a result is maintaining itself on a long-term basis as a viable component of its habitat. The conservation status of the species is considered to be favourable.

WOOD SANDPIPER


DUNLIN


COMMON SCOTER


GREENSHANK



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WIGEON

8.5.85 A maximum of 400 pairs of wigeon breed in Scotland each year with a wintering population of nearly 100,00050.

8.5.86 Six flights of this species were recorded during the VP surveys with the largest flock of 22 individuals recorded on 9th December 2011 north of Lochend Figure 8.25.

8.5.87 This species was not recorded during the Caithness Lochs survey.

8.5.88 This species was recorded eight times during the roaming survey near the Proposed Development with most of the observations recorded north of Hoy Figure 8.26.

8.5.89 Wigeon is potentially vulnerable to collisions and sensitive to disturbance events and is also considered to have moderate behavioural sensitivity.

8.5.90 The population of this species within the SPA is stable and maintaining itself on a long-term basis as a viable component of its habitat and as such the conservation status of the species is considered to be favourable.

Species Descriptions – North Caithness Cliffs SPA Species

RAZORBILL


PEREGRINE

8.5.92 There are around 600 pairs of peregrine in Scotland with twice as many, between 2,000-2,500 individuals, present in winter51.

8.5.93 Peregrines are usually present on breeding territories in the Highlands from March-September, after which they often migrate to winter in lowland and coastal areas. The birds inhabiting nest sites on the North Caithness Cliffs SPA are likely to be present there year round. This species was recorded occasionally throughout the year's survey. A total of three flights, all of a single bird, were recorded over the course of the year's VP survey (Figure 8.27). Two flights were recorded near Mayfield approximately 1 km north of the Proposed Development and one flight was recorded near Hoy crossing the Proposed Development at collision risk height. This species was not recorded during the Caithness Lochs survey or the roaming survey.

8.5.94 A total of five peregrine flights were recorded during the additional winter surveys (Figure 8.28). Three flights were recorded at Lochend with one of them crossing the Proposed Development at collision risk height. One flight was recorded crossing the LOD near Fryster at collision risk height and the last flight was recorded north of the Proposed Development at South Weydale.

50 Ib id 51 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady.


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8.5.95 Peregrines are potentially vulnerable to collision with power lines when displaying, mobbing avian intruders and hunting. The species regularly nests on human structures in some parts of the world, including buildings in Scottish cities such as Perth and Edinburgh, but not usually in the north of Scotland. Static disturbance range from 500-750 m, but some individual peregrines are tolerant of human activity. North of Scotland peregrines are considered to be much more sensitive to human disturbance than in other parts of due to widespread deliberate illegal persecution and their typically isolated nest locations and so are considered to be of high behavioural sensitivity.

8.5.96 In the absence of data on the population change of this species within the SPA, its conservation status is unknown. However, the population of peregrine inhabiting similar conditions on the nearby East Caithness Cliffs SPA has declined slightly and so it seems likely that the same could be true of the North Caithness Cliffs SPA population and that the population's conservation status may be unfavourable as a result of the species not maintaining itself on a long term basis as a viable component of its habitat.

ATLANTIC PUFFIN


NORTHERN FULMAR


BLACK-LEGGED KITTIWAKE


COMMON GUILLEMOT


Other Species – Wildfowl

MUTE SWAN

8.5.101 There are about 1,000 breeding pairs of mute swan Cygnus olor in Scotland but this increases to up to 8,000 birds with the arrival of overwintering birds from elsewhere.

8.5.102 One flight of this species was recorded during the VP survey of one bird near Weydale approximately 350 m west of the Proposed Development (Figure 8.29).

8.5.103 Four flights by the species were recorded during the Caithness Lochs survey. Two flights were recorded at Loch Watten (Figure 8.30), one of two birds soon after dawn on 22nd February 2012 and a single bird soon after dusk on 1st March 2012.


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PINK-FOOTED GOOSE

8.5.105 As many as 200,000 pink footed geese overwinter in Scotland, although they often do not remain throughout the whole winter, continuing south to sites in England. As such, there are peak numbers recorded in October with a similar peak in March/April albeit smaller as birds migrate north in smaller groups52.

8.5.106 Pink-footed goose Anser brachyrhynchus flights were recorded frequently along the length of the Proposed Development throughout the autumn/winter period (Figure 8.31). The first record was made on 13th September 2011 and the last on 12th April 2012. A total of 58 flights were recorded with a maximum flock size of 900 birds.

8.5.107 A total of 155 flights of pink-footed goose were recorded during the additional winter surveys (Figure 8.32). The largest flocks consisted of approximately 1,000, 750 and 600 individual birds with the majority of flights recorded near Hilliclay and Lochend.

8.5.108 This species was also recorded frequently during the Caithness Loch Survey. A total of 14 flights were recorded at Loch of Mey with a maximum flock size of 3,000 birds (Figure 8.33a). A total of 29 flights were recorded at Loch Heilen with a maximum flock size of 2,100 birds (Figure 8.33b). A total of 52 flights were recorded at Lochs Scarmclate and Watten (Figure 8.33c). From the timing of the flights around dawn and dusk, it appears that this species is roosting at the sites along with the qualifying interest species of the SPA. The locations in which the species was recorded correlate with the locations that observers completing survey work for the SNH report into the Caithness Lochs found the species feeding.

8.5.109 This species was recorded frequently and in large flocks during the roaming survey (Figure 8.34). Concentrations of geese were observed in the Bowermadden with flocks as large as 1500 geese recorded on 7th April 2012, and a mixed flock of pink-footed geese and greylag geese of up to 2000 individuals near Loch Heilen on 8th March 2012. Other flocks of this species consisted of 12-500 individuals.

8.5.110 This species is considered to have moderate behavioural sensitivity for the reasons discussed previously for other goose species.

BEAN GOOSE

8.5.111 As few as 20 tundra bean geese Anser fabalis rossicus move through Scotland each year on passage with approximately 250 taiga bean geese Anser fabalis fabalis overwintering in two separate populations, one near Falkirk and one in Dumfries and Galloway53. These separate subspecies breed in different habitats in Scandinavia and Siberia.

8.5.112 Three records of tundra bean goose were recorded during the VP survey, two records near Durran of 19 individuals each flight and one record of 14 individuals near Weydale (Figure 8.35).

8.5.113 One flight of bean geese was recorded during the Caithness Lochs survey with 50 bean geese recorded at Loch Scarmclate at dusk on 14th March 2012 (Figure

52 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady. 53 Ib id


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8.36). They are likely to be birds on a stopover during the spring migration northeast to their breeding grounds in northern Europe and may be more likely to be taiga bean goose Anser fabalis fabalis.


8.5.115 This species is considered to have moderate behavioural sensitivity for the reasons discussed previously for other goose species.

BARNACLE GOOSE

8.5.116 70,000 birds (20% of the world population of barnacle goose Branta leucopsis) overwinter in Scotland. The birds are from two distinct populations with those found on the west and north coast, including Caithness and Sutherland, typically from Greenland and those on the east coast and Solway Firth, from Svalbard, Norway.

8.5.117 This species was recorded once during the VP survey. A single flight was recorded on 23rd November 2011 consisting of six individuals northwest of Bowermadden (Figure 8.37). The species was not recorded during the Caithness Lochs Survey.

8.5.118 This species was not recorded during the Caithness Lochs survey or roaming survey.

8.5.119 This species is considered to have moderate sensitivity for the reasons discussed previously for other goose species.

TEAL

8.5.120 One flight by teal Anas crecca was recorded during the VP survey. Seven birds were seen on 9th November 2011 north of Bowermadden near Moss of Greenland (Figure 8.38).

8.5.121 No teal flights were recorded during the Caithness Lochs survey.

8.5.122 This species was recorded six times during the roaming survey. All records were made south of Castletown near Borgie Mains (Figure 8.39). The largest flock was recorded 30th November 2011 of 100 individuals and a mixed flock of teal, wigeon and mallard were recorded on 17th December 2011 of 200 individuals.

MALLARD

8.5.123 30 mallard Anas plathyrhynchos flights were recorded during the course of the VP survey. Flights were recorded along all sections of the Proposed Development and in all months of the VP survey apart from January and July. Most flights recorded were of one to three birds, on 14th September 2011 a flock of eight birds were recorded at Philips Mains (Figure 8.40).

8.5.124 A total of two mallard flights were recorded during the additional winter surveys as shown on Figure 8.41. Both flights were recorded north of the Proposed Development near Hilliclay.

8.5.125 Only two mallard flights were recorded during the Caithness Lochs survey. The flights were recorded at Loch Watten with one bird seen on 21st March 2012 and another on 13th April 2012 (Figure 8.42).


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8.5.126 14 observations of this species were made during the roaming survey. Eight of the observations were made near Borgie Mains with observations spread throughout the year. The largest flock recorded was of 120 individuals at Borgie Mains, with mixed flocks including teal and wigeon ranging from 50 to 300 (Figure 8.43).

TUFTED DUCK

8.5.127 No tufted duck Aythya fuligula flights were recorded during the VP survey.

8.5.128 One flight was recorded during the Caithness Lochs survey (Figure 8.44) with two birds recorded at Loch Watten on 14th October 2011.

8.5.129 No records were made during the roaming survey.

GOOSANDER

8.5.130 No goosander Mergus merganser flights were recorded during the VP survey or additional VP survey.

8.5.131 No flights by the species were recorded during the Caithness Lochs survey.

8.5.132 No records made during the roaming survey.

Other Species – Cormorants and Herons

CORMORANT

8.5.133 No cormorant Phalacrocorax carbo flights were recorded during the VP survey.

8.5.134 A total of one cormorant flight was recorded during the additional winter surveys as shown on Figure 8.45. The flight was of a single bird crossing the Proposed Development near Hilliclay.

8.5.135 Three flights by the species were recorded during the Caithness lochs survey. Two flights by single birds were recorded at Loch Scarmclate on 1st March 2012 and another flight by a single bird was recorded at Loch Watten on 22nd February 2012 (Figure 8.46).


GREY HERON

8.5.137 A total of 29 flights by grey heron Ardea cinerea were recorded during the VP survey with all flights being of one or two birds (Figure 8.47). Flights were recorded in most sections of the Proposed Development and throughout both the winter and summer months.

8.5.138 Only one heron flight was recorded during the additional winter surveys as shown on Figure 8.48. The flight consisted of two individual birds which crossed the Proposed Development at Hollandmey Moss.

8.5.139 A total of four flights by this species were recorded during the Caithness Lochs survey. Four flights by single birds were recorded at Loch Watten (Figure 8.49), one on 22nd February 2012 and three on 21st March 2012.

8.5.140 This species was recorded five times during the roaming survey (Figure 8.50). Most records were observed near Borgie Mains of one, two and four individuals.


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One record of a single bird was recorded near Moss of Greenland 20th August 2012.

Other Species – Raptors

RED KITE

8.5.141 No Red kite Milvus milvus flights were recorded during the VP survey or additional VP survey.



SPARROWHAWK

8.5.144 12 flights by sparrowhawk Accipiter nisus, always of a single bird, were recorded during the VP survey. The majority of flights were recorded around Hollandmey (Figure 8.51).

8.5.145 A total of 12 sparrowhawk flights were recorded during the additional winter surveys (Figure 8.52). Five of the flights were recorded near Syster with one flight crossing the Proposed Development. The other seven flights were recorded between South Weydale and Fryster with two individual flights crossing the Proposed Development.



BUZZARD

8.5.148 Buzzard Buteo buteo flights, typically of a single bird, were recorded on 123 occasions throughout the year during the VP survey. Flights were recorded in all sections of the Proposed Development and throughout both the winter and summer months (Figure 8.51).

8.5.149 A total of 45 buzzard flights were recorded during the additional winter surveys (Figure 8.52). The buzzard flights were spread out over the additional survey areas from Weydale to Fryster and from Reaster to Syster.

8.5.150 No buzzard flights were recorded during the Caithness Lochs survey.

8.5.151 This species was recorded 30 times throughout the year during the roaming survey. The activity was spread along the Proposed Development (Figure 8.53).

OSPREY

8.5.152 Up to 200 pairs of osprey Pandion haliaetus breed in Scotland54. They are summer migrant visitors to the Highlands and are usually recorded between April and September.

8.5.153 Osprey was recorded once during the VP survey of two individual birds on 31st July 2012 near Moss of Greenland (Figure 8.51).

54 Forrester et al (2007) The Birds of Scotland. SOC, Aberlady.


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8.5.154 No records were made of this species during the Caithness Lochs survey.

8.5.155 No records were made of this species during the roaming survey.

8.5.156 Osprey are known to nest in Caithness, however the small number of flight records would indicate that no nests occur close to the Proposed Development.

KESTREL

8.5.157 79 kestrel Falco tinnunculus flights were recorded during the VP survey. The flights were spread thought most of the Proposed Development with slightly more activity around Moss of Greenland (Figure 8.51). The species was seen throughout all months of the VP surveys from 2011 to 2012.

8.5.158 A total of 15 kestrel flights were recorded during the additional winter (Figure 8.52). The majority of the kestrel flights were recorded around the area of Lochend, with a total of four flights crossing the Proposed Development.


8.5.160 One kestrel flight was recorded during the roaming survey on 26th July 2012 near Hall of Slickly (Figure 8.53).

Other Species – Waders

8.5.161 All of the species of wader listed below are considered to have moderate behavioural sensitivity to disturbance and potential collision risk (Figures 8.54-8.57).

OYSTERCATCHER

8.5.162 58 oystercatcher Haematopus ostralegus flights were recorded during the VP survey. Most records were between one to four birds and observations of this species were made frequently near Waydale, Bowermadden and to a lesser extent at Philips Mains (Figure 8.54).


8.5.164 56 records were made of this species during the roaming survey. Most records were made between Thurso and Moss of Greenland (Figure 8.57). The records were between one to four individuals and almost exclusively seen between May to July 2012.

LAPWING

8.5.165 110 lapwing Vanellus vanellus flights were recorded during the VP survey with numbers ranging between single birds up to a maximum flock size of 570 birds recorded near Philips Mains 3rd August 2012 (Figure 8.54). Activity was recorded along the full length of the Proposed Development with activity highest in August.

8.5.166 A total of eight lapwing flights were recorded during the additional winter surveys (Figure 8.55). Six of the lapwing flights were recorded between Reaster and Lochend with a total of four flights crossing the LOD of the Proposed Development. A further two flights were recorded near Hilliclay with both flights crossing the Proposed Development.


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8.5.167 The species was recorded on two occasions during the Caithness Lochs survey with a flock of 35 birds at Loch Scarmclate on 3rd November 2011 and a flock of 38 seen at Loch Watten on 22nd February 2012 (Figure 8.56).

8.5.168 77 records were made of this species throughout the roaming survey area with records spread throughout the Proposed Development. The largest flock of 900 lapwings was recorded 9th August 2012 south of Castletown near Borgie Mains (Figure 8.57).

SNIPE

8.5.169 Six snipe flights were recorded during the VP survey (Figure 8.54).


8.5.171 This species was recorded one time during the roaming survey. South-east of Moss of Greenland a single bird was observed on 15th June 2012 (Figure 8.57).

BLACK-TAILED GODWIT

8.5.172 No records of black-tailed godwit Limosa limosa were made during the VP survey or additional VP survey.


8.5.174 This species was recorded twice during the roaming survey. A flock of five individuals was observed near the A9 road 21st September 2011, and a flock of three was recorded near Hilliclay 7th September 2011 (Figure 8.57).

WHIMBREL

8.5.175 Two flights of Whimbrel Numenius phaeopus flights were recorded during the VP survey with two birds seen near Hoy 20th June 2011 and one bird seen near Philips Mains 19th June 2012 (Figure 8.54).



CURLEW

8.5.178 112 curlew flights were recorded during the VP survey. Most records were of single birds with occasional flocks of four individuals. Flights were recorded along the Proposed Development with higher activity found around the Moss of Greenland area (Figure 8.54).

8.5.179 Two curlew flights were recorded during the Caithness Lochs survey with two flocks, one of 20 and the other of 28 birds seen flying at Loch Watten on 14th March 2012 (Figure 8.56). These flocks possibly represent birds returning to the peatlands from their coastal wintering areas.

8.5.180 This species was recorded frequently during the roaming survey between Thurso, Thurso and Gills Bay. Most records were frequent throughout the Proposed Development the largest flocks of 65 and 23 birds near Tain and Philips Mains on the 14th July 2012 and 29th June 2012 respectively (Figure 8.57).


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REDSHANK

8.5.181 One redshank flight was recorded during the VP survey on 15th August 2012 near Philips Mains (Figure 8.54). This is likely to be a bird breeding in the surrounding moorland.


8.5.183 Two observations were made of this species during the roaming survey, both of one bird. Both records were made on the 15th June 2012 north and northwest of Moss of Greenland (Figure 8.57).

Other Species – Gulls

GREAT BLACK-BACKED GULL

8.5.184 146 great black-backed gull Larus marinus flights were recorded during the VP survey (Figure 8.58). Typically these were flights of single birds but there were occasional records of two - five birds. Flights were recorded in all months of the survey and in all sections of the Proposed Development.


8.5.186 This species was recorded 27 times during the roaming survey. Most records were of individual birds with occasional observations of two and three birds. Frequent records were in the areas around Hilliclay and Philips Mains (Figure 8.59).

Other Species - Crows

RAVEN

8.5.187 Two raven Corvus corax flights were recorded during the VP survey (Figure 8.60). One record was of an individual bird near Philips Mains on 3rd August 2012. The other record was of 20 birds northeast of Moss of Greenland on 13th August 2012.



Breeding Bird Survey

8.5.190 The following tables provide details of the species recorded during the breeding bird survey completed in spring-summer 2012. Each table provides the list of species recorded, the number of records made of that species and the number of those records that represent either confirmed or possible breeding records. Where appropriate, it is noted in the final column of each table if the species is a species of high conservation concern (red-listed, SOHCC) or medium conservation concern (amber-listed, SOMCC) as listed in the Birds of Conservation Concern 3 review. All other species are not of conservation concern55.

8.5.191 A total of 33 species were recorded during the breeding bird survey shown in Figures 8.61a-f. This does not include the five species of wading birds which are dealt with separately below. Of the 33 species, six were species of high

55 Eaton M.A., Brown A.F., Noble D.G., Musgrove A.J., Hearn R.D., Aebischer N.J., Gibbons D.W. Evans A. and Gregory R.D.

(2009) Birds of Conservation Concern 3: The population status of birds in the United Kingdom, Channel Islands and the Isle of Man. British Birds 102: 296-341


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conservation concern of which three were confirmed or possible breeding species. 11 species were of medium conservation concern of which six were confirmed or possible breeding species. Five Highland Biodiversity Plan (HBAP) and four Caithness Biodiversity Action Plan (CBAP) species were records. The suite of birds recorded is considered to be typical of Caithness with a relatively diverse suite of birds but less than half being species of conservation concern.

Table 8.4: Breeding Bird Survey (Also shown on Figures 8.61a-f)

BTO Code Species Breeding Status: Total Number records with number of confirmed breeding records in brackets

Conservation Status

B Blackbird Turdus merula

7(7)

BZ Common buzzard Buteo buteo

21 (0)

C Carrion crow Corvus corone

1 (0)

CH Chaffinch Fringilla coelebs

12 (12)

CK Common cuckoo Cuculus canorus

1 (0) SOHCC,HBAP

CT Coal tit Periparus ater

8 (8)

FP Feral pigeon Columba livia

1 (0)

GB Great-black backed gull Larus marinus

7 (0) SOMCC

GC Goldcrest Regulus regulus

1 (1)

GJ Greylag goose Anser anser

3 (0) SOMCC

H Grey heron Ardea cinerea

2 (0)

HH Hen harrier Circus cyaneus

1 (0) SOHCC,

K Kestrel Falco tinnunculus

5 (0) SOMCC

LI Linnet 1 (0) SOHCC, HBAP, CBAP


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Conservation Status

Carduelis cannabina

MA Mallard Anas platyrhynchos

12 (2) SOMCC

MP Meadow pipit Anthus pratensis

3 (3) SOMCC

MS Mute swan Cygnus olor

1 (0)

M Mistle thrush Turdus viscivorus

1 (1) SOMCC

NX Great skua Stercorarius skua

1 (0) SOMCC

PH Pheasant Phasianus colchicus

3 (0)

RB Reed bunting Emberiza schoeniclus

2 (2) SOMCC, HBAP, CBAP

RG Red grouse Lagopus lagopus scotica

3 (0) SOMCC,HBAP

RN Raven Corvus corax

2 (0)

S Skylark Alauda arvensis

97 (97) SOHCC, HBAP, CBAP

SH Sparrowhawk Accipiter nisus

4 (0)

SI Common swift Apus apus

1 (1) SOMCC

SK Siskin Carduelis spinus

2 (2)

ST Song thrush Turdus philomelos

1 (1) SOHCC, CBAP


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Conservation Status

SW Sedge warbler Acrocephalus schoenobenus

1 (1)

WP Woodpigeon Columba palumbus

1 (1)

WR Wren Troglodytes troglodytes

10 (10)

WW Willow warbler Phylloscopus trochilus

13 (13) SOMCC

Y Yellowhammer Emberiza citronella

1 (1) SOHCC

Waders recorded during the breeding bird survey

8.5.192 A total of five species of wading birds were recorded during the breeding bird survey (Figures 8.62a-f). All of the wading bird species that were recorded are species of conservation concern with two species of high conservation concern recorded and three species of medium conservation concern. Two Highland Biodiversity Action Plan (HBAP) species were recorded.

Table 8.5: Breeding Wader Survey (Also shown on Figures 8.62a-f)

BTO Code Species Breeding Status: Total number of confirmed breeding records in brackets

Conservation Status

CU Curlew Numenius arquata

70 (8) SOMCC, HBAP

L Lapwing Vanellus vanellus

55 (41) SOHCC, HBAP

OC Oystercatcher Haematopus ostralegus

37 (19) SOMCC

RK Redshank Tringa tetanus

3 (0) SOMCC

SN Snipe Gallinago gallinago

8 (2) SOHCC


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8.6 Potential Impacts OHL


HABITAT LOSS

8.6.1 Both permanent and temporary habitat loss have been assessed in Chapter 7: Ecology. The levels of habitat loss are low and are not considered to represent a significant loss of bird habitat.

NEST DESTRUCTION

8.6.2 Construction activities have the potential to remove habitat in which nests occur, in the construction area.

DISTURBANCE

8.6.3 Construction activity may result in temporary displacement of birds. During construction, birds would be disturbed by the activities of personnel and the movements of vehicles and other machinery. Birds are known to habituate to constant and regular visual disturbance, but impacts might arise from noise disturbance.


COLLISION RISK

8.6.4 Any birds flying over the Proposed Development, but especially raptors, geese and swans, are at potential risk of collision with the conductor and earth wires. Collision with a wire may result in death of the bird and consequently impact on the population of the species.

8.6.5 Line markers have been shown to reduce collisions by 78%56, this figure has been used in the CRA to correct for flights that flew in the area of Durran where line markers would be installed as mitigation.

8.6.6 Full details are provided in Technical Appendix 8.2.

ELECTROCUTION

8.6.7 Bird electrocution on OHLs is possible either where a bird is able to touch a conductor while it is perched on an earthed tower; touch a conductor and the earth wire simultaneously; or touch two conductor wires simultaneously. The configuration of the wires and towers of the Proposed Development mean that none of those scenarios is likely.

DISTURBANCE (DISPLACEMENT)

8.6.8 When operational, the Proposed Development would require a low level of staffing and consequent activity by site personnel both on foot and in vehicles. This activity may disturb bird species. In addition, the Proposed Development may result in disturbance effects arising from noise and visual effects associated with the wires.

56 Barrientos R., Alonso J.C., Ponce C. and Palacin C. (2011). Meta-analysis of the Effectiveness of Marked Wire in Reducing

Avian Collisions with Power Lines.


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BARRIER EFFECTS

8.6.9 The Proposed Development may create a “barrier” to the movement of bird species with the vertical configuration of wires and towers creating an actual or perceived barrier which bird species may not cross or at the very least would need to habituate to crossing. Both geese and swans were observed to modify flights to avoid the existing 132 kV OHL during VP surveys for the Dounreay to Mybster 275 kV OHL, which suggests the possibility that birds may habituate to the presence of a new structure.

PERCHING AND NESTING LOCATIONS

8.6.10 In the relatively treeless Caithness landscape, the towers of the Proposed Development may provide opportunities for birds such as raptors by providing hunting perches or locations from which to advertise territories. The towers of the Proposed Development will also offer potential nesting locations for birds, ospreys in Scotland sometimes use the structures as nesting sites57.

Underground Cable


HABITAT LOSS

8.6.11 Both permanent and temporary habitat loss have been assessed in Chapter 7: Ecology. The levels of habitat loss are low and are not considered to represent a significant loss of bird habitat.

NEST DESTRUCTION

8.6.12 Construction activities have the potential to remove habitat in which nests occur in the construction area.

DISTURBANCE

8.6.13 Construction activity may result in temporary displacement of birds. During construction, birds would be disturbed by the digging of the trench for the underground cable, activities of personnel and the movements of vehicles and other machinery. Birds are known to habituate to constant and regular visual disturbance, but impacts might arise from noise disturbance.


8.6.14 Any operational repairs and maintenance to the underground cable have the potential to disturb and destroy any breeding bird habitat that has successively developed during the operation of the Proposed Development.

8.7 Mitigation Mitigation by Design


AVOIDANCE OF KEY LOCATIONS

8.7.1 An iterative process of corridor and route selection has been completed to identify the optimal alignment for the Proposed Development (see Chapter 4 Route

57 http://www.rspb.org.uk/discoverandenjoynature/discoverandlearn/birdguide/name/o/osprey/nesting.aspx


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Selection and Alternatives). Ornithology was a key consideration throughout and along with other environmental constraints ensured that key locations such as the various designated sites were avoided (See Chapter 4 Route Selection and Alternatives).


8.7.2 A preliminary Collision Risk Assessment (CRA) was conducted which subsequently led to the development of a mitigation strategy of undergrounding the approximately seven kilometre section from Reaster to Gills Bay. In the absence of any mitigation, this section was estimated to cause 100 whooper swan collisions per annum and 10.2 Greenland greater white-fronted goose collisions per annum. The approximately three kilometre section from Thurso South substation to South Weydale would be undergrounded to mitigate for landscape and visual impacts (see Chapter 6 LVIA for further information).



TIMING OF CONSTRUCTION IN KEY CAITHNESS LOCHS SPA SPECIES AREAS

8.7.3 Where works are proposed in the area around the key goose and swan loafing and foraging area of the fields around Ha’ of Durran, the CEMD/CEMP would include method statements and risk assessments setting out the approach to timing of works and methodologies to be followed would be agreed with SNH prior to construction commencement.

8.7.4 It is proposed that pre-construction surveys would identify those areas in use by the goose and swan species at the time of the works. Buffer zones would be established around the key fields and those sections of the Proposed Development that fall within the buffer zones would be scheduled to avoid disturbance. In this way impacts on birds that feed and loaf in this area would be avoided.

TIMING OF VEGETATION REMOVAL

8.7.5 In order to reduce the impact on the assemblage of breeding birds found in the vicinity of the Proposed Development and once the final tower locations, including micro-siting has been agreed, vegetation due to be removed to facilitate construction – such as within the associated works LOD to accommodate access tracks and at the tower footprints would be removed ahead of the bird breeding season (March-August). A Construction Environmental Management Document CEMD/CEMP would include procedures for the timing and methods of vegetation removal. In this way, birds on site would be discouraged from using those areas where construction activity would be occurring. This procedure is considered to reduce the impact on bird species as by clearing the areas, the birds which previously used the areas have the opportunity to find alternative nesting locations elsewhere.

DETERRENCE MEASURES

8.7.6 In order to prevent any birds identified on site as potential breeders from settling, deterrence measures would be considered. These may include: • iridescent tape across the construction areas prior to construction;

• bird deterring devices which produce intermittent loud noises; and


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• walking of the cleared areas on a regular basis to prevent birds settling and to monitor if any birds are settling to nest on areas close to planned construction activity.

PRE-CONSTRUCTION BIRD SURVEY

8.7.7 If construction activities are planned to occur during the bird breeding season (March-August), a pre-construction survey, would be completed as per the CEMD/CEMP, to check whether birds are settling to nest within the LOD of the Proposed Development and to check for any Annex 1 or Schedule 1 species such as hen harrier nesting within disturbance distance of the LOD.

NEST BUFFER ZONES

8.7.8 The CEMD/CEMP would contain the pre-agreed Species Protection Plans (SPP). The Birds SPP contains procedures dealing with the protection of any active nest identified during pre-construction surveys. Specific measures would be defined in site specific environmental management plans.


TIMING OF CONSTRUCTION IN KEY CAITHNESS LOCHS SPA SPECIES AREAS

8.7.9 Where works are proposed in the following locations, method statements and risk assessments would be agreed with SNH prior to construction commencement: • the areas east of Loch Heilen: Lochend and Syster; and

• the area around Philips Mains.

8.7.10 It is proposed that pre-construction surveys would identify those areas in use by the goose and swan species at the time of the works. Buffer zones would be established around the key fields and those sections of the undergrounding that fall within the buffer zones would be scheduled to avoid disturbance. In this way impacts on birds that feed and loaf in this area would be avoided.

TIMING OF VEGETATION REMOVAL

8.7.11 In order to reduce the impact on the assemblage of breeding birds found on site and micro-siting has been agreed, vegetation due to be removed to facilitate construction – such as within the associate works to accommodate access tracks and the trenches for the undergrounding would be removed ahead of the bird breeding season (March-August). The CEMD/CEMP would include procedures for the timing and methods of vegetation removal. In this way, birds on site would be discouraged from using those areas where construction activity would be occurring. This procedure is considered to reduce the impact on bird species as by clearing the areas, the birds which previously used the areas have the opportunity to find alternative nesting locations elsewhere.

DETERRENCE MEASURES

8.7.12 In order to prevent any birds discovered at an early stage of settlement from settling, deterrence measures would be considered. These may include: • iridescent tape across the construction areas prior to construction;

• bird deterring machines which produce intermittent loud noises; and


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• walking of the cleared areas by people on a regular basis to prevent birds settling and to monitor if any birds are settling to nest on areas close to planned construction activity.

PRE-CONSTRUCTION BIRD SURVEY

8.7.13 If construction activities are planned to occur during the bird breeding season (March-August), a pre-construction survey, would be completed as per the CEMD/CEMP to check whether birds are settling to nest within the LOD of the Proposed Development and to check for any Annex 1 or Schedule 1 species such as hen harrier nesting close to the LOD.

NEST BUFFER ZONES

8.7.14 The CEMD would contain the pre-agreed Species Protection Plans (SPP). The Birds SPP contains procedures dealing with the protection of any active nest identified during pre-construction surveys. Specific measures would be defined in site specific environmental management plans.



LINE MARKERS

8.7.15 Based on the results of the CRA, line markers would be positioned on the earth wires along an approximate 5km section of the Proposed Development from approximately tower TGB 15 by Fryster to tower TGB 35 at Wester Olrig. The exact tower numbers would be confirmed during the detailed design development.

MAINTENANCE FOR OHL

8.7.16 Any maintenance required on the OHL will be timed to take place outside of sensitive times such as the bird breeding season. Where this is not possible then surveys will be planned to take bird sensitivities into consideration and may involve undertaking ornithological walkover surveys as detailed in the CEMD/CEMP.


8.7.17 Although the underground cable would not require routine maintenance, there could be a requirement to access the cable by excavation to undertake emergency repairs. Such repairs could have the potential to disturb geese and swans during the winter periods. If geese or swans were present when repairs to the underground cable were needed, bird deterring machines would be placed in the areas to be affected so as to encourage birds to feed/loaf in adjacent fields. Likewise, during the summer periods care would need to be taken if vegetation has been allowed to grow so that breeding birds are likely to nest above the underground cable. In such a case it is suggested that vegetation be cut prior to the breeding period if possible, or if not a suitable trained ornithologist should survey the area for breeding birds prior to any repairs taking place. All methods described will be detailed in the CEMD/CEMP.


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8.8.1 This section assesses the residual impacts on bird species taking into account the mitigation measures described above. Throughout this section, unpublished 2009 data provided by SNH has been used to help estimate SPA bird populations58.

Proposed Activity, Duration, Biophysical Change and Relevance to Receptor in Terms of Ecological Structure and Function

8.8.2 The construction of the Proposed Development is anticipated to finish in 2019 and would result in a new OHL and underground cable in an area where bird species breed in spring and summer months, and feed and rest during all months of the year. The construction of the Proposed Development, prior to mitigation, could potentially result in a variety of adverse impacts upon bird species including disturbance, displacement, habitat destruction and nest destruction. Once operational, without mitigation, the Proposed Development could represent a collision risk for some species, create a barrier effect and may give rise to disturbance associated with maintenance activities. As such, the birds which currently inhabit the area at various times of the year may be unable to continue to behave or survive as at present and any alterations to their behaviour or survival could affect the integrity of populations at varying geographic scales.

Impacts on Caithness Lochs SPA Species

Rationale for Prediction of Effect on Integrity of the Caithness Lochs SPA Qualifying Interests

8.8.3 All three Caithness Lochs SPA qualifying interest species, Greenland greater white-fronted goose, Icelandic greylag goose and Icelandic whooper swan were recorded during the various surveys completed both in the vicinity of the Proposed Development and at the nearby component sites of the SPA. All three species utilised fields in the area of the Proposed Development for feeding and loafing and all three were recorded flying across the route of the Proposed Development at certain locations. Other than greylags, flights across the Proposed Development tended to be concentrated in discrete locations rather than to occur equally across the entire length of the Proposed Development.

Residual Construction Impacts OHL

BIRD HABITAT IMPACTS

8.8.4 The component lochs of the Caithness Lochs SPA and Ramsar site lie at least 1.5 km from the Proposed Development. Therefore, no land-take would occur within the Caithness Lochs SPA and Ramsar site (Chapter 2: Description of Development details how and where construction work would take place) and no direct or indirect habitat loss would occur. All construction and operational work would take place outwith the designated sites. Consequently, no effects from direct land-take on Caithness Lochs SPA bird habitats would occur.

8.8.5 All three SPA qualifying interest species are not confined to the Caithness Lochs SPA component sites whilst overwintering as evidenced by the flightlines recorded during both the VP surveys and the Caithness Lochs survey and by the results of the roaming survey. The birds tend to roost within the SPA and then use habitats in the wider area, including some within the LOD of the Proposed Development for

58 Scottish Natural Heritage. 2012. Cumulative Assessment spreadsheet for wind farms – Caithness and Sutherland.


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feeding and loafing. As such, construction activities on habitats outwith the SPA boundary, but used by SPA qualifying interest species for feeding and loafing have the potential to adversely impact upon the conservation objectives of the SPA, by impacting upon the habitats that support the species. However, land-take associated with the Proposed Development would be minimal, limited to access tracks and tower footprints. Also some habitat loss would only be temporary with re-vegetation occurring at tower compounds following completion of construction activities. The results of the VP surveys; roaming survey; the SNH Caithness Lochs Survey; additional winter surveys; and the GWFG Small Sites Study show that along most of the Proposed Development the observation of the species falls outwith the LOD. Whooper swan activity along the Proposed Development was higher at Durran Mains and Moss of Greenland as identified from the VP survey and roaming survey. Whooper swans were recorded to use fields adjacent to the LOD. Greylag geese were recorded in similar locations to whooper swan, though at much higher densities. All three species are of international value and moderately sensitive to impacts. However, loss of a small part of their feeding and loafing areas would have a low magnitude, short term, reversible and extremely unlikely impact and consequently no significant effects on the Caithness Lochs SPA qualifying interest species from habitat loss are predicted to occur.

Disturbance

8.8.6 The Greenland greater white fronted goose (GWFG) are extremely localised in their usage of the area around the Proposed Development, and were not recorded to use any area along the Proposed Development and around the associated LOD.

8.8.7 Similarly during the additional winter surveys GWFG were only recorded in areas away from the associated LOD.

8.8.8 The greylag geese are less localised in their usage of the area around the Proposed Development than the Greenland Greater White Fronted Goose. However, increased flight activity is evident in the surrounding areas of Durran and to a lesser degree, Moss of Greenland. A total of 97 flocks of greylag geese were recorded during the VP surveys, with almost 50% of these flights coinciding with the Proposed Development and the associated LOD. As such, the species is considered to utilise the fields by, and near the LOD of the Proposed Development. The avoidance of construction works around Durran between the months of October - early April would reduce impacts on the species further. Construction disturbance is assessed to have a possible (5-50%) temporary, low magnitude impact on the species. This impact is not ecologically significant.

8.8.9 Whooper swan flocks were recorded in similar locations to the greylag geese, albeit with far fewer flocks recorded. 16 of the flocks were recorded within the LODs of the Proposed Development during VP surveys. Flocks of whooper swan were abundant near Hoy during the roaming surveys. The avoidance of construction activities in the vicinity of Hoy during the winter months would ensure that no impacts on this key location would occur. This species is considered to have many alternative sites to utilise in the event of construction disturbance, with many over one km from the LODs. Construction disturbance is assessed to have and extremely unlikely, temporary, low magnitude impact on the species. This impact is not ecologically significant.


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Residual Construction Impacts Underground Cable

BIRD HABITAT IMPACTS

8.8.10 The component lochs of the Caithness Lochs SPA and Ramsar site lie at least 400 m from the proposed undergrounded sections. Therefore, no land-take would occur within the Caithness Lochs SPA and Ramsar site (Chapter 2: Description of Development highlights how and where construction work would take place) and no direct or indirect habitat loss would occur. All construction and operational work would take place outwith the designated sites. Consequently, no effects from direct land-take on Caithness Lochs SPA bird habitats would occur.

8.8.11 The birds tend to roost within the SPA and then use habitats in the wider area, including some within the LOD of the Proposed Development for feeding and loafing. As such, construction activities on habitats outwith the SPA boundary, but used by SPA qualifying interest species for feeding and loafing have the potential to adversely impact upon the conservation objectives of the SPA, by impacting upon the habitats that support the species. However, land-take associated with the Proposed Development would be minimal and temporary, limited to the cable trench and a temporary haul road parallel to the excavation trench. Re-vegetation would occur along the cable trench and associated haul road following completion of construction activities. The results of the VP survey, roaming survey; the SNH Caithness Lochs Survey; and the GWFG Small Sites Study show that along most of the Proposed Development the observation of the species falls outwith the LOD. However, there is evidence from the GWFG small sites study report that the species frequently use fields adjacent to and within the LOD northeast of Loch Heilen59. The GWFG population that habitually uses the Loch of Mey and Loch Heilen as well as the adjacent fields has consistently numbered 100-250 birds, with this declining to a low of 110 in 2012 and then increasing recently to 163 birds in 201460. The VP surveys identified frequent flights near Philips Mains of GWFG that are likely travelling between Loch of Mey and fields near the LOD as interpreted by flight lines from VP surveys and the GWFG small sites study report. The fields used by GWFG identified during the GWFG small sites study report show that the fields in use lie outwith the LOD for the Proposed Development, as well as outwith the area for the proposed Gills Bay substation. Therefore, little or no habitat in frequent use by Greenland Greater White Fronted Goose is likely to be affected. Whooper swan activity along the undergrounded section of the Proposed Development was higher at Philips Mains as identified from the VP survey and roaming survey. Whooper swans were recorded to use fields adjacent to the LOD. Greylag geese were recorded in similar locations to whooper swan, though at much higher densities. All three species are of international value and moderately sensitive to impacts. However, loss of a small part of their feeding and loafing areas would have a low magnitude, short term, reversible and extremely unlikely impact and consequently no significant effects on the Caithness Lochs SPA qualifying interest species from habitat loss are predicted to occur.

Disturbance

8.8.12 The Greenland greater white fronted geese are extremely localised in their usage of the area around the Proposed Development. A population of the species use Lochs of Mey and Heilen, both component sites of the Caithness Lochs SPA, and is typically found feeding and loafing within arable and pasture fields in the vicinity

59 Francis, I., Mitchell, C., Griffin, L. And Fox, T. 2011. Greenland White-fronted Geese: Land use and conservation at small

wintering sites in Scotland. http://greenlandwhitefront.org/publications/small-sites-report/ 60 Data request from RSPB: Numbers from roost counts on Loch Heilen and Loch Mey.


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of Loch Heilen and Philips Mains adjacent and within the undergrounding LOD of the Proposed Development. As such activities in that area during the months of October to April when the species is typically present in Caithness, would result in disturbance of the species as the birds may be unable to use feeding and loafing areas. The birds are extremely faithful to these fields having been recorded using them by the GWFG study for many years. With a moderate sensitivity to disturbance and a moderate impact magnitude, as less than 20% of the species' feeding areas fall with the LODs, an ecologically significant impact is considered possible61. GWFG are known to feed and loaf in the fields from where the road crosses the proposed undergrounded section at Lochend, to approximately where the proposed undergrounded section enters the conifer plantation at Hollandsmey. Therefore, by avoiding construction work in the identified areas between October and early April, impacts could be avoided as the species would be able to feed and loaf as normal. As such, construction disturbance would have no impact on Greenland greater white-fronted geese from the SPA and no ecologically significant effects are predicted.

8.8.13 The greylag geese are less localised in their usage of the area around the Proposed Development than the Greenland greater white-fronted geese. However, increased flight activity is evident in the surrounding areas of Philips Mains. The avoidance of construction works around Philips Mains between the months of October - early April would reduce impacts on the species further. Construction disturbance is assessed to have a possible temporary, low magnitude impact on the species. This impact is not ecologically significant.

8.8.14 Whooper swan flocks were recorded in similar locations to the greylag geese, albeit with far fewer flocks recorded. Flocks of whooper swan were abundant near Loch Heilen during the roaming surveys. The avoidance of construction activities next to Loch Heilen during the winter months would ensure that no impacts on this key location would occur. This species is considered to have many alternative sites to utilise in the event of construction disturbance, with many over one km from the LOD. Construction disturbance is assessed to have an extremely unlikely temporary, low magnitude impact on the species. This impact is not ecologically significant.

Residual Operational Impacts OHL

COLLISION RISK

8.8.15 A Collision Risk Assessment has been completed for the species recorded during both the original VP surveys in 2011/2012 and the additional winter surveys in 2014-15 for the SPA qualifying interest species. It is important to note however that the CRA for the species recorded during the additional surveys is not directly comparable to the CRA for the 2011-12 surveys. This is due to the fact that the additional surveys cover a smaller proportion of the Proposed Development and associated LOD, compared to the area covered by the 2011-12 surveys.

8.8.16 As can be seen in Figure 8.3 and Figure 8.4, all of the GWFG flights were recorded in the Phillips Mains area, and as this section of the Proposed Development is to be undergrounded, the Proposed Development would have no effect on the GWFG SPA population. In addition, evidence set out within Mitchell et al (2011)62 notes

61 Francis, I., Mitchell, C., Griffin, L. And Fox, T. 2011. Greenland White-fronted Geese: Land use and conservation at small

wintering sites in Scotland. http://greenlandwhitefront.org/publications/small-sites-report/ 62 Mitchell, C. et al (2011) Greenland White-fronted geese: Investigating causes of low reproductive output in Greenland –

report to SNH.


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that the decline in this population is linked to a decline in productivity as a result of reduced breeding success of the species whilst on their Greenland breeding grounds, rather than to the number of available breeding birds. It is considered that the mitigation provided by undergrounding the Proposed Development from Reaster to the new proposed substation at Gills Bay, will mean that no impact would occur on the Greenland greater white-fronted geese population.

8.8.17 The overall collision risk to greylag geese from the Proposed Development has been calculated to be 31.11 birds per annum. However, with the addition line markers to mitigate this risk, (reduction of 78% as per Barrientos et al63) in the section from Fryster to Wester Olrig, this number is reduced to 11.72 birds per annum64 or approximately 0.13 % of the SPA population. The loss of 11.72 birds per annum is a permanent adverse impact on an internationally important receptor with moderate behavioural sensitivity. The magnitude is considered to be low as it affects less than 1 % of the population. The population of the species using the SPA is increasing. The annualised rate of increase, based on the change between the 1998 designation figures and the most recent SNH counts in 2009 is approximately 2 % or 173 geese and for this reason, the population is considered to have favourable conservation status. The predicted mortalities resulting from collision risk are less than the rate of increase in the SPA population and as such no overall reduction in the numbers of greylag geese using the SPA is predicted. As such, no ecologically significant impact on the species from collision risk is predicted. Additionally, the northern Scottish greylag goose population has recently been reduced by a cull of up to 5,500 birds in Orkney as a result of the impact of the birds on farming interests on the islands65. The number of birds impacted by the Proposed Development is far smaller than those being removed elsewhere.

8.8.18 The additional winter surveys produced an overall collision risk to greylag geese of 11.31 birds per annum which was reduced to 11.21 with the addition of line markers to mitigate collision risk from Fryster to Wester Olrig. The fact that mitigation only reduced the collision risk from 11.31 to 11.21 birds per annum is because most of the area west of Fryster was not visible from the additional VPs, which is where most flights were recorded during the 2011-12 surveys. This also highlights the fact that the surveys from 2011-12 and 2014-15 are not directly comparable to each other, but act as complementary information. It is impossible to say if the area west of Fryster would have a similar collision risk in 2014-15 as in 2011-12 had it been surveyed along with the Achingills and Weydale VPs in the additional winter surveys. However, it does seem likely that the estimated number of greylag collisions of 11.72 birds per annum calculated from the 2011-12 surveys is actually slightly higher. This would have a minimal impact on the SPA population, and it is not considered that the Proposed Development would have a significant impact on this species.

8.8.19 This model provides an estimate of collision risk as a result of the Proposed Development. For a significant impact the prediction would need to increase by 78.43 birds per annum with this representing an error of 669%. This is considered highly unlikely to occur.


Avian Collisions with Power Lines. 64 Note that not all flights would be mitigated for by line marking, hence the total reduction is less than 78% 65 http://www.snh.gov.uk/news-and-events/press-releases/press-release-details/?id=777


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8.8.20 The overall collision risk to whooper swan from the Proposed Development has been calculated to be 9.19 birds per annum. However, with the addition of line markers as mitigation, (reduction of 78% as per Barrientos et al66) in the area from Fryster to Wester Olrig this number is reduced to 2.44 birds per annum67, or approximately 1.17 % of the SPA population. The loss of 2.44 birds per annum is a permanent adverse impact on an internationally important receptor with moderate behavioural sensitivity. The magnitude is considered to be low as it affects approximately between 1-5 % of the whooper swan SPA population. It is important to consider that the avoidance rates for birds avoiding powerlines used in the model are guidelines for wind farms and not powerlines, but are recommended by SNH to use until such rates are published. Also, all goose species have had a revised avoidance risk from 99 % to 99.8 % by SNH in 2013, whereas whooper swan is still considered to have an extremely conservative estimate of only 98 % avoidance, which is a major contributor to the results of 2.44 birds per annum. Population viability studies of whooper swans commissioned by SNH (2012)68 showed that population simulations which were run for periods of 25 years predicted that a whooper swan population in Scotland would increase at an average rate of almost 5 % per year. The model predicted that removing 1 % of the population each year would decrease the population growth rate by approximately 1.3 %, therefore by removing 4 % would cause a population decrease due to a growth rate of less than 1. The estimated reduction of 1.17 % of the SPA population due to the Proposed Development is therefore predicted to reduce the growth rate for whooper swan by approximately 1.5 %, i.e. the population would still be increasing by approximately 3.2 % per year.

8.8.21 The additional winter surveys produced an overall collision risk of 3.1 birds per annum. This collision risk is based on a single flight of 11 birds which is the only flight of whooper swan which was observed during the 2014-15 surveys crossing the OHL section of the Proposed Development. As for greylags, these CRA numbers are not directly comparable to the surveys of 2011-12. When viewing the flight distribution of the 2011-12 surveys on Figure 8.10 it is evident that the majority of flights crossing the LOD were in the area from Fryster to Wester Olrig where line marker mitigation would be implemented. It is therefore considered that the initial assessment of 2.44 birds per annum is not altered.

8.8.22 The estimate of 2.44 birds per annum would need to increase to 7.5 birds per annum before a significant impact would be predicted. This would represent an error of 307% which is considered highly unlikely to occur.

DISTURBANCE

8.8.23 An operational OHL would require some maintenance and routine inspection. Occasional visits by staff involving both vehicular and pedestrian movement to inspect and maintain towers and wires are considered to be likely to occur along with vehicular and pedestrian activity associated with landowners. In addition, whilst some landowners have an interest in moving wildfowl on from their land in order to reduce crop damage and would utilise specific measures to disturb them, activities associated with the Proposed Development would not in any way directly target them. No Ecologically Significant Impact on Caithness Lochs SPA qualifying interest species is predicted.


Avian Collisions with Power Lines. 67 Note that not all flights would be mitigated for by line marking, hence the total reduction is less than 78% 68 Trinder, M. (2012). The Potential consequences of elevated mortality on the population viability of whooper swans in relation

to wind farm developments in Northern Scotland.


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BARRIER EFFECTS

8.8.24 The operational OHL could create a physical barrier preventing bird movements across it. All three SPA species, move between loch roost locations and field feeding and loafing locations and a barrier to that movement would be an adverse impact. However, the most active section for Greenland greater white-fronted geese near Gills Bay would be undergrounded. Whooper swans were also active in the area that would be undergrounded, but may be affected by the barrier effect in the area of Durran where lime markers would be installed. However, there are already a number of OHLs in the vicinity of the Caithness Lochs SPA that the birds regularly cross between their roost and feeding/loafing locations. This includes an existing 132 kV steel lattice tower line between Dounreay and Thurso which was within the VP survey area for the Dounreay to Mybster 275 kV OHL. During those VP surveys, both geese and swans were frequently seen flying over and under the wires of the existing 132 kV OHL. Also, both geese and swans were seen to adjust their flights in order to cross the barrier created by the existing OHL. For example, flocks of whooper swans flying north from Loch Lieurary were seen to fly into the prevailing wind to gain sufficient height to then fly over the top of the 132 kV OHL. Some of these flights then continued at height, but in others, the birds quickly lost height once across the OHL and landed in fields to the north. These observations indicate that whilst the Proposed Development is a potential barrier, in reality, the wildfowl species that inhabit the area are able to move past OHLs successfully and have to some degree, habituated to their presence. As such, no ecologically significant impacts on the Caithness Lochs SPA species, as a result of barrier effects, are predicted.

Residual Operational Impacts Underground Cable

8.8.25 No operational impacts of the undergrounding sections of the Proposed Development on the Caithness Lochs SPA qualifying interest species are predicted to occur.

Summary

8.8.26 No ecologically significant impacts on greylag or Greenland greater white-fronted goose of the Caithness Lochs SPA qualifying interest species are predicted and with the mitigation implementations of line markers from Fryster to Wester Olrig only a minor effect is likely for whooper swan, as such no effects on the integrity of the SPA would occur as a result of the Proposed Development.

Impacts on Caithness and Sutherland Peatlands SPA Species

Rationale for Prediction of Effect on Integrity of the Caithness and Sutherland Peatlands SPA Qualifying Interests

8.8.27 Five of the 12 Caithness and Sutherland Peatlands SPA species, short-eared owl, hen harrier, merlin, golden plover and wigeon were recorded during the various surveys. Of the five species, all apart from short-eared owl were recorded in flight during the VP survey. Short-eared owl was recorded twice during the Caithness Lochs survey. Activity by the various species was localised rather than spread equally across the entire length of the Proposed Development. The areas with greatest activity were Moss of Greenland and Hill of Slickly, with most flights consisting of hen harrier and golden plover.


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LAND-TAKE OR BIRD HABITAT IMPACTS

8.8.28 The component sites of the Caithness and Sutherland Peatlands SPA and Ramsar lie at least 3,300 m from the Proposed Development. Therefore, no land-take would occur in the Caithness and Sutherland Peatlands SPA and Ramsar site (Chapter 2: Description of Development highlights how and where construction work would take place), so no direct or indirect habitat loss would occur because all construction and operational work would take place outwith the designated sites. Consequently, no ecologically significant effects from direct land-take on Caithness and Sutherland Peatlands SPA bird habitats are predicted.

8.8.29 The winter flight records indicate areas with higher usage by hen harrier in the area surrounding Moss of Greenland with flights recorded in both the area of the OHL and the undergrounded section of the Proposed Development. As the SPA boundary is over three km southeast of that area, it may be that the harriers seen were not SPA birds. Even if, with a precautionary approach, it is considered that they are, the activity is low and restricted to the winter months and not indicative of a nearby nest. Two species were recorded on the ground in the vicinity of the Proposed Development during the roaming surveys, golden plover and wigeon. Golden plover was recorded approximately 100 m north-east of the Proposed Development at Durran, while wigeon was recorded approximately 1,100 m west of the Proposed Development at Wester Olrig. As such, no flocks were recorded within the LOD of the Proposed Development and an ecologically significant impact from habitat loss on Caithness and Sutherland Peatlands SPA qualifying interest species is considered extremely unlikely. Were it to occur then the impact would be low magnitude, short term and reversible.

DISTURBANCE

8.8.30 Due to the transitory and occasional nature of activity by short-eared owl and merlin in the vicinity of the Proposed Development, no ecologically significant impacts on these species are predicted as a result of construction disturbance.

8.8.31 Similarly, hen harrier winter activity around Moss of Greenland is transitory and occasional in nature. As such a short term adverse impact of construction disturbance on hen harriers is assessed to be of low magnitude, reversible and extremely unlikely to be an ecologically significant impact.

8.8.32 As stated above, golden plover activity was not linked to breeding birds within the LOD of the Proposed Development with no records made of breeding birds. As such, disturbance would be more significant to wintering golden plover as SPA birds move into the area around the Proposed Development from their breeding grounds within the peatlands. However, feeding flocks were not abundant. As stated above, only 10 records were made during the roaming survey and some of those were of birds outwith the winter period and none were recorded within the LOD. As such, the temporary adverse impact of construction disturbance on golden plover is assessed to be of low magnitude and extremely unlikely to be an ecologically significant impact.


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8.8.33 Land take or bird habitat impacts from the underground cable section are the same as those for the OHL; assessed in paragraphs 8.8.26 and 8.8.27, above.

DISTURBANCE

8.8.34 Disturbance impacts for the construction of the underground cable are the same as those for the OHL; assessed in paragraphs 8.8.28 to 8.8.30, above.


COLLISION RISK

8.8.35 Very low flight activity was recorded by short-eared owl and merlin. No ecologically significant impacts from collision risk are predicted.

8.8.36 The overall collision risk to hen harrier from the Proposed Development has been calculated to be 1.89 birds per annum or approximately 10.5 % of the SPA population. The loss of up to 2 birds per annum is a permanent adverse impact on an internationally important receptor with high behavioural sensitivity. The magnitude is considered to be high as it affects over 10 % of the population. The population of the species using the SPA is decreasing. The annualised rate of decrease, based on the change between the 1999 designation figures and the most recent SNH counts in 2009 is approximately 3% or 0.84 harriers per annum and for this reason, the population is considered to have unfavourable conservation status. The loss of up to 2 birds per annum could affect both the conservation status and integrity of the species, resulting in a likely adverse ecologically significant impact.

8.8.37 However, this assessment has considered all hen harriers seen during the surveys to be birds from the SPA even though they were recorded 3.3 km from the SPA and is likely to be an overestimate as other wider countryside birds would occur. The majority of the flights along the Proposed Development that caused a collision risk of 1.89 birds per annum were recorded during the winter periods at a time when hen harriers are known to gather in roosting sites from as far away as continental Europe. The winter population for hen harriers in Scotland have been estimated between 1,050 – 1,540 birds69. It is not possible to quantify this overestimate, however it is believed that at the very least it means that impacts on the SPA population would be neutral.

8.8.38 Only one hen harrier flight was recorded crossing the LOD of the OHL at collision risk height during the additional winter surveys, the CRA of this flight is considered negligible and therefore the previously calculated collision risk of 1.89 birds per annum is taken as the worst case.

8.8.39 The overall collision risk to golden plover from the Proposed Development has been calculated to be 12.32 birds per annum or approximately 0.58 % of the SPA population. The loss of 12 birds per annum is a permanent adverse impact on an internationally important receptor with moderate behavioural sensitivity. The magnitude is considered to be low as it affects less than 1 % of the population.

69 R.W., Andrews, I.J., McInerny, C.J., Murray, R.D., McGowan, R.Y., Zonfrillo, B., Betts, M.W., Jardine, D.C. & Grundy, D.S.

(eds) 2007. The Birds of Scotland. The Scottish Ornithologists’ Club, Aberlady.


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Also, it is important to note that most of the golden plover flights were recorded during the winter months and are therefore likely not to be of the SPA population. The UK as a whole has approximately four times as many golden plovers during the winter periods than during the breeding season. The population of the species using the SPA is stable and for this reason, the population is considered to have favourable conservation status. It is also important to consider that as for whooper swans the avoidance rates used were developed for wind farms and are extremely conservative with only 98 % avoidance rates. The effect of the Proposed Development to this species would likely be low magnitude, short-term, reversible and extremely unlikely on the Caithness and Sutherland SPA population.

BARRIER EFFECTS

8.8.40 No ecologically significant barrier effect impacts are predicted on any of the SPA species recorded. All five species are generally low-flying and flights observed during VP surveys for the Dounreay - Mybster 275 kV OHL were recorded flying across the route of the existing 132 kV OHL, typically underneath the wires of that OHL. For example, one record of golden plovers from the roaming survey was of birds in a field immediately adjacent to the consented Thurso substation. In order to reach this location, the flock would almost certainly have had to negotiate at least one OHL.

Residual Operational Impacts Underground Cable

8.8.41 No operational impacts of the undergrounding sections of the Proposed Development on the Caithness and Sutherland Peatlands SPA qualifying interest species are predicted to occur.

Summary

8.8.42 No ecologically significant impacts on any of the Caithness and Sutherland Peatlands SPA qualifying interest species are predicted and as such no effects on the integrity of the SPA would occur as a result of the Proposed Development.

Impacts on North Caithness Cliffs SPA Species

Rationale for Prediction of Effect on Integrity of the North Caithness Cliffs SPA Qualifying Interests

8.8.43 Only one of the six North Caithness Cliffs SPA qualifying interest species: peregrine was recorded during the surveys. No other Qualifying Interest Species were recorded.



8.8.44 The component sites of the North Caithness Cliffs SPA lie at least 4 km from the OHL of the Proposed Development. Therefore, no land-take would occur in the North Caithness Cliffs SPA, so no direct or indirect habitat loss would occur because all construction and operational work would take place outwith the designated sites. Consequently, no ecologically significant effects from direct land-take on North Caithness Cliffs SPA bird habitats are predicted.

8.8.45 Only peregrine was recorded during the surveys, with just three flights seen. These flights were transitory and occasional and as such not considered to be in any way a function of the habitats in the area of the Proposed Development. As


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such, no ecologically significant effects on peregrine are predicted from habitat change from the Proposed Development.

DISTURBANCE

8.8.46 As stated above, peregrine activity was occasional and transitory and the species did not appear to use the area of the Proposed Development for anything other than passing through and as such no ecologically significant impacts from disturbance are predicted.



8.8.47 The component sites of the North Caithness Cliffs SPA lie at least 5,400 m from the undergrounding sections of the Proposed Development. Therefore, no land-take would occur in the North Caithness Cliffs SPA, so no direct or indirect habitat loss would occur within the SPA. No ecologically significant effects from direct land-take on North Caithness Cliffs SPA bird habitats are predicted.

8.8.48 As mentioned above only peregrine was recorded during the surveys, with just three flights observed. As such, no ecologically significant effects on peregrine are predicted from habitat change from the Proposed Development.

DISTURBANCE

8.8.49 As stated above, peregrine activity was occasional and transitory and the species did not appear to use the area of the Proposed Development for anything other than passing through and as such no ecologically significant impacts from disturbance are predicted.


COLLISION RISK

8.8.50 Very low flight activity by peregrine was recorded: no ecologically significant impacts from collision risk are predicted.

BARRIER EFFECTS

8.8.51 Given the extremely low level of activity and the inherent manoeuvrability of the species, no ecologically significant barrier effects on peregrine from the Proposed Development are predicted.


8.8.52 No operational impacts of the undergrounding sections of the Proposed Development on the North Caithness Cliffs SPA qualifying interest species are predicted to occur.

Summary

8.8.53 No ecologically significant impacts on any of the North Caithness Cliffs SPA qualifying interest species are predicted and as such no effects on the integrity of the SPA would occur as a result of the Proposed Development.


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Impacts on Wider Countryside Species

Mute swan

8.8.54 One flight of mute swan was recorded during the VP survey with only four flights recorded during the Caithness Lochs survey. The species was not recorded during the roaming survey. As such, the Proposed Development is extremely unlikely to have a significant impact upon the species.

OHL

8.8.55 The flock was recorded outwith the OHL LOD of the Proposed Development. This species is considered to have many alternative sites to utilise in the event of construction disturbance. Construction disturbance and habitat loss are therefore not predicted to have any impact on the species.

8.8.56 As no flights were recorded flying across the Proposed Development, no flights at collision height were recorded and so no impact form collision risk is predicted to occur. It is considered that as the species is present in the area and uses many of the sites that other wildfowl use; it is possible that it does fly across the LODs of the Proposed Development. However, even if there had been flights recorded, the level of activity would be low enough that any collision risk would not be an ecologically significant impact.

UNDERGROUND CABLE

8.8.57 The flock was recorded outwith the underground sections of the Proposed Development. This species is considered to have many alternative sites to utilise in the event of construction disturbance. Construction disturbance and habitat loss are therefore not predicted to have any impact on the species.

Pink-footed goose

8.8.58 The species was recorded on 58 occasions during the VP survey and 95 times during Caithness Lochs survey with flights observed at Lochs Mey, Heilen, Scarmclate and Watten. This species was also recorded frequently during the roaming surveys. As such, the Proposed Development have the potential to impact upon the species.

OHL

8.8.59 Pink-footed geese tend to overwinter elsewhere in Scotland and Britain. For example large winter roosts form at the Loch of Strathbeg in Aberdeenshire and at Loch Leven in Perth and Kinross. The species does not overwinter in Caithness in notable numbers; rather it is typically recorded there on passage with other occasional and transitory flocks seen. As such, the habitats in the area of the Proposed Development are only used for short periods in autumn and spring and an ecologically significant impact from habitat loss extremely unlikely.

8.8.60 Similarly, due to the occasional nature of usage by the species, OHL construction disturbance is not predicted to have an ecologically significant impact on pink-footed geese.

8.8.61 The overall collision risk to the species from the Proposed Development has been calculated to be 19.46 birds per annum, though with line marker mitigation from Fryster to Wester Olrig this number is reduced to 8.17 or approximately 0.004% of


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the 200,000 birds that pass through Scotland each year. The species is not a qualifying interest species of any SPA in the vicinity of the Proposed Development. As such no ecologically significant impact on the species from collision risk is predicted.

UNDERGROUND CABLE

8.8.62 Due to the occasional nature of usage by the species, undergrounding construction disturbance is not predicted to have an ecologically significant impact on pink-footed geese.

Other goose species

OHL

8.8.63 Bean geese and barnacle geese were also recorded during the survey, however only as infrequent, incidental records. A total of one barnacle goose flight and three bean goose flights were recorded during VP surveys and one bean goose flight during the Caithness Lochs Survey. With such low levels of activity, habitat loss or disturbance impacts are considered to be negligible and not ecologically significant. Collision risk is considered to be a negligible, ecologically non-significant impact for both species.

UNDERGROUND CABLE

8.8.64 With the low level of activity for bean geese and barnacle geese recorded during the surveys no habitat or disturbance impacts are considered ecologically significant.

Wildfowl – ducks

8.8.65 Three species of duck were recorded during the various surveys. Activity by the species was very occasional apart from mallard which was recorded 30 times during the VP Surveys, twice during the Caithness Lochs Surveys and 14 times during the roaming surveys. As such the Proposed Development has the potential to impact on wider countryside duck species, including some species that are features of SSSIs in the local area.

OHL

8.8.66 Only mallard was recorded within the LOD of the Proposed Development during the breeding bird survey. However, this bird tends to use aquatic and wetland habitats rather than the terrestrial habitats where construction activity would be occurring. As such, no impact from habitat loss on wider countryside duck species is predicted. Similarly, no impact from construction disturbance is predicted.

8.8.67 Due to either no flights being recorded or no flights at collision height, no impact from collision risk on all species apart from mallard. As it is an extremely abundant species, an ecologically significant collision risk impact on mallard is not predicted to occur.

8.8.68 With typically low flight style no ecologically significant impacts on duck species from barrier effects are predicted.


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UNDERGROUND CABLE

8.8.69 The low presence of duck species recorded during the surveys it is not considered that the undergrounding of the Proposed Development would have either habitat or disturbance impacts on these species.

Osprey

8.8.70 Osprey is a migratory schedule 1 species, which was recorded flying on only one occasion during the VP survey. The flight was recorded near Moss of Greenland. Due to the low activity of this species the Proposed Development is considered to have a negligible impact upon the species.

OHL

8.8.71 Habitat loss or construction disturbance would not have any impact upon the species as ospreys do not utilise the habitats of the Proposed Development or any immediately adjacent fishing locations such as the River Thurso.

8.8.72 With only one flight seen to cross the LODs of the Proposed Development, no ecologically significant impact on the species from collision risk is predicted to occur.

8.8.73 Given the extremely low level of activity and the observations of the species flying across over the existing 132 kV OHL during the Dounreay - Mybster 275 kV OHL VP surveys, no ecologically significant barrier effects on osprey from the Proposed Development are predicted.

UNDERGROUND CABLE

8.8.74 Habitat loss or construction disturbance would not have any impact upon the species as ospreys do not utilise the habitats of the Proposed Development or any immediately adjacent fishing locations such as the River Thurso.

Other raptors

8.8.75 Three other raptor species were recorded during the surveys with buzzard, kestrel and sparrowhawk all recorded frequently. As such, the Proposed Development has the potential to adversely impact these species.

OHL

8.8.76 All three species are typically tree nesting and as such, the largely treeless LODs of the OHL of the Proposed Development and its surrounding area are only used by hunting birds and birds passing across the area. As such, the temporary adverse impacts of habitat loss and construction disturbance on other raptors in the wider countryside are assessed to be of low magnitude along most of the OHL sections of the Proposed Development.

8.8.77 All three species were recorded flying the vicinity of the existing 132 kV OHL during VP surveys for the Dounreay - Mybster 275 kV OHL. All three species also commonly perch on human structures such as electricity towers. Sparrowhawks have a low flight style in order to surprise their prey species, whilst both buzzards and kestrels were recorded at various flight heights. However, all three species were recorded crossing the existing 132 kV OHL, including flights under, through and over the wires. As a result of these observations and given the relative


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abundance of these three species, no ecologically significant impacts from collision risk are predicted. Similarly, no ecologically significant impacts from barrier effects are predicted to occur.

UNDERGROUND CABLE

8.8.78 All three species are typically tree nesting and as such, the northeast end of the Proposed Development near Phlilips Mains holds the most suitable habitat for these species. All three species utilise territories and areas that extend much wider than the LODs of the Proposed Development and therefore would have alternative hunting locations and locations to utilise in the event of construction activity. Localised activity was recorded, near Phlilips Mains the area which contains the only significant conifer woodland along the Proposed Development. This area was frequently used by buzzards which were recorded 26 times during the VP surveys in this area. As such, the temporary adverse impacts of habitat loss and undergrounding construction disturbance on other raptors are assessed to be of medium impact towards the northeast end of the Proposed Development.

Wading birds

8.8.79 Seven wading bird species other than those discussed already as part of the Caithness and Sutherland Peatlands SPA were recorded during the various surveys. Some were recorded during the winter months, but most were recorded during the summer breeding season. All are species of either high or medium conservation concern. The Proposed Development have the potential to have an adverse impact on these species.

OHL

8.8.80 The most frequent recorded waders were curlew and oystercatchers which were observed more often near Weydale and Bowermadden. Whimbrel and redshank were only recorded once each crossing the LOD, near Wester Olrig and Reaster respectively, during the VP surveys. In addition, oystercatcher, curlew and lapwing were recorded frequently during the roaming survey. As such the habitats of the Proposed Development and surrounding area are important to wading birds and the loss of some of them, even temporarily, would have an adverse impact on the suite of wading birds considered to be of local importance. The adverse impact would be a temporary, low magnitude impact on moderately sensitive receptors and is considered unlikely to be an ecologically significant impact.

8.8.81 The potential impact of construction disturbance on wading birds would be very similar to the impact of habitat loss. There are breeding records of four species from the breeding bird survey and any of those breeding attempts could have been disturbed or the nests destroyed by construction activities associated with the OHL of the Proposed Development. Construction disturbance would be an adverse temporary, low magnitude impact on moderately sensitive receptors. The impact is considered to be unlikely to result in an ecologically significant impact.

8.8.82 Collision risk is not considered to be an ecologically significant impact for the wading bird species due to the few flights recorded for most species. In addition, those flights that were recorded tend to be low flights in common with typical wader flights. More than five flights were recorded for only two species: curlew and lapwing. Flights of both of these species were most frequent in the winter months between Dounreay and Thurso. No calculation of collision risk for these species


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has been completed given the abundance of both and their generally low flight styles. A negligible impact that is not ecologically significant is predicted.

8.8.83 Barrier effect impacts are similarly not predicted to be significant as wading birds were observed flying across the OHL of the existing 132 kV OHL between Dounreay and Mybster during VP surveys for that project.

UNDERGROUND CABLE

8.8.84 The most frequent recorded waders were curlew and oystercatchers which were observed more often near Syster and Philips Mains. In addition oystercatcher, curlew and lapwing were recorded frequently during the roaming survey. As such the habitats of the undergrounding LODs of the Proposed Development and surrounding area are important to wading birds and the loss of some of them, even temporarily, would have an adverse impact on the suite of wading birds considered to be of local importance. The adverse impact would be a temporary, low magnitude impact on moderately sensitive receptors and is considered unlikely to be an ecologically significant impact.

8.8.85 The potential impact of construction disturbance on wading birds would be very similar to the impact of habitat loss. There are breeding records of four species from the breeding bird survey and any of those breeding attempts could have been disturbed or the nests destroyed by construction activities associated with the undergrounding of the Proposed Development. Construction disturbance would be an adverse temporary, low magnitude impact on moderately sensitive receptors. The impact is considered to be unlikely to result in an ecologically significant impact.

Breeding Birds

OHL

8.8.86 33 species of bird were recorded during the breeding bird survey. Not all of the species recorded were breeding. However, given the low ecological value of the majority of the habitats of the Proposed Development, it is a relatively diverse suite of birds including 17 species of conservation concern. As such, the Proposed Development has the potential to adversely impact breeding birds.

8.8.87 The birds recorded during the breeding bird survey utilise the habitats within and outwith the Proposed Development for breeding. Smaller passerine species which dominate the suite of breeding birds recorded, have small territories in the order of 100s of metres. As such, where these territories lie entirely or mostly within the LODs, habitat loss could be significant, conversely, if the territory is on the edge of the LODs, it would remain largely un-impacted. There is also abundant similar habitat immediately adjacent to the LODs of the Proposed Development that the species could use instead. The suite of breeding birds is considered to be of county importance. The temporary adverse impact of habitat loss would be low and unlikely to be an ecologically significant impact.

8.8.88 By virtue of their smaller territories, the impact of disturbance on breeding bird species would, as for habitat loss, potentially result in a number of territories being uninhabitable or result in birds finding other suitable nest locations within the territory, outwith the zone of disturbance of the construction activities. Again, alternative locations are considered to exist for the species to utilise in the event of disturbance. The temporary adverse impact of construction disturbance would be low and unlikely to be ecologically significant.


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8.8.89 No collision risk or barrier effect impacts are predicted for breeding birds.

UNDERGROUND CABLE

8.8.90 As mentioned above, though there were low levels of bird activity recorded during the BBS the birds that were recorded were a diverse suite including species of conservation concern. As such, the undergrounding of the Proposed Development have the potential to impact adversely upon breeding birds.

8.8.91 The territories of small passerines that are small could be significantly impacted by habitat loss however there is an abundance of similar habitat nearby to reduce this impact. The suite of breeding birds is considered to be of county importance. The temporary adverse impact of habitat loss would be low and unlikely to be an ecologically significant impact.

8.8.92 By virtue of their smaller territories, the impact of disturbance on breeding bird species would, as for habitat loss, potentially result in a number of territories being uninhabitable or result in birds finding other suitable nest locations within the territory, outwith the zone of disturbance of the construction activities. Again, alternative locations are considered to exist for the species to utilise in the event of disturbance. The temporary adverse impact of construction disturbance would be low and unlikely to be ecologically significant.

Breeding Wading Birds

8.8.93 Four out of the five waders recorded during the breeding bird survey were confirmed as possibly breeding, two of which are of high conservation concern and two of which are of medium conservation concern.

OHL

8.8.94 Two of the confirmed possible breeding wader species were recorded within the OHL LOD of the Proposed Development, namely curlew and lapwing. With the LOD measuring at most 300 m, but mostly approximately 100 m in width along the Proposed Development, any of the breeding waders recorded are likely to have territories that range beyond the Proposed Development, where similar habitat is abundant. The temporary adverse impact of construction disturbance would be low and unlikely to be ecologically significant.

UNDERGROUND CABLE

8.8.95 Two of the confirmed possibly breeding wader species were recorded within the undergrounding LOD of the Proposed Development, namely oystercatcher and lapwing. Oystercatcher are known to breed at densities of 0.5-2.0 pairs/km² in typical agricultural land in Scotland, lapwing at approximately 1 pair/km² and snipe at 0.62 pairs/km²70. Even at the highest densities of 2 pairs/km² of oystercatcher, a single territory is likely to cover 0.5 km². With the LOD measuring at most 300 m, but mostly approximately 100 m in width along the Proposed Development, any of the breeding waders recorded are likely to have territories that range far beyond the Proposed Development, where similar habitat is abundant. The temporary adverse impact of construction disturbance would be low and unlikely to be ecologically significant.

70 R.W., Andrews, I.J., McInerny, C.J., Murray, R.D., McGowan, R.Y., Zonfrillo, B., Betts, M.W., Jardine, D.C. & Grundy, D.S.

(eds) 2007. The Birds of Scotland. The Scottish Ornithologists’ Club, Aberlady.


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Ornithology

Limitations

8.8.96 It is appropriate to note that the collision risk for the Proposed Development represents a worst case and precautionary assessment. Also, the calculated risk window of 5 m to 35 m was used throughout the Proposed Development even though the risk window of individual spans vary. However, it is assumed that the individual pylon heights and subsequently wire heights represents a range of both a narrower as well as wider collision risk window throughout the OHL of the Proposed Development, and therefore the conservative estimate of 5 m – 35 m collision window should represent a suitable average for the entire OHL.

8.8.97 During the VP surveys, height bands were measured at different heights than 5 m to 35 m and therefore in order to be precautionary, many flights that are likely to have flown above 35 m have been included in the risk window. For example, flights that were only recorded as above 15 m have all been considered to be within 5 m and 35 m, whereas where flights were recorded as up to 10 m by the observer, 50 % were considered to be below 5 m and 50 % were considered to be within 5 and 10 m, as suggested by SNH (2014)71 (see Technical Appendix 8.2 for further details).

8.9 Cumulative Effects Habitat Loss

8.9.1 Cumulative developments in the local area would also result in the loss of habitat. However, unlike the majority of the habitat impacts associated with the Proposed Development which are temporary until construction is completed, many of the cumulative schemes such as the Thurso South and Gills Bay substation sites would result in a permanent habitat loss as the habitats would be replaced by buildings and hardstanding. The Dounreay to Mybster 275 / 132 kV OHL would have a similar temporary impact on habitats as the Proposed Development. The nearest cumulative wind farm developments (Earl’s Cairn at Lochend, Coghill at Bowermadden, Stemster south of Durran and Buckies Hill south-west of Thurso south substation) would result in limited habitat loss impacts as the land take of such schemes is limited to turbine footprints and access tracks which have been micro-sited to avoid the most sensitive habitats. Additionally wind farm schemes usually require habitat management plans to enhance the remaining habitats on site. As such, no ecologically significant impacts on ornithological receptors from habitat loss are predicted.

Disturbance

8.9.2 Similar to the issue of habitat loss, construction disturbance from the cumulative wind farm schemes is considered to be negligible and a non-significant impact. Disturbance associated with the two substations has the potential to create a cumulative impact in combination with the Proposed Development. However, in order to mitigate the impact of the Proposed Development, construction activities in the vicinity of the River Thurso and therefore close to the Thurso South substation would not occur during the winter months when key ornithological species are present. The Dounreay to Mybster 275 / 132 kV OHL has the potential to result in a cumulative disturbance impact, particularly on wildfowl species. However, the impact on those species from the Proposed Development was assessed not to be ecologically significant as it avoids the key feeding and loafing areas as well as the

71 Estimating Bird Collision Risk with Power Lines. SNH. March 2014 (DRAFT).


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designated sites themselves. Similar to the issue of habitat loss, disturbance associated with wind farm schemes situated on heathland habitats would not impact on Caithness Lochs SPA species as their key habitat is the farmland in the area. Disturbance effects on the Caithness and Sutherland Peatland SPA species are likely. As such, even in combination, there are considered to be sufficient alternative locations for the species to use and so no ecologically significant impact is predicted.

Collision Risk

8.9.3 In order to calculate the cumulative collision risk of the Proposed Development, as shown in Table 8.6, data provided by SNH relating to existing calculated collision risk for other projects in the Caithness and Sutherland region was utilised72.

Table 8.6: Cumulative Collision Risk

Species Project Collision Risk post mitigation

Caithness and Sutherlands Region Cumulative Collision Risk

Combined Cumulative Collision Risk

% of SPA population

Greenland greater white-fronted goose

0 birds per annum N/A N/A N/A

Greylag goose 11.72 birds per annum

144.22 birds per annum (Caithness Lochs SPA)

155.94 birds per annum

1.71 %

Whooper swan 2.44 birds per annum

3.29 birds per annum (Caithness Lochs SPA)


2.75 %

Hen harrier 1.89 birds per annum

1.81 birds per annum (Caithness and Sutherland Peatlands SPA)73

3.7 birds per annum

N/A74

Golden plover 12.32 birds per annum

13.261 birds per annum (Caithness and Sutherland Peatlands SPA)


1.2 %

Pink-footed goose 8.17 birds per annum



N/A75

8.9.4 With the exception of whooper swan, the cumulative collision risks are all considered to be negligible and not result in ecologically significant impacts.

72 Note the SNH data considers all known development projects in Caithness and Sutherland. The list of other development

projects for particular consideration with respect to the Proposed Development has been set out within Table 2.4 “Cumulative Developments” in Chapter 3 “EIA Process and Methodology.”

73 The Hen Harrier collision risk at Camster Wind Farm was reduced from 0.6 in SNH’s original table to 0.06 following clarification from SNH, and Strathy Wood was included (0.11 birds per annum) – email 25 June 2015 from David Law (SNH Senior Casework Officer) as part of the procedure for Strathy South Wind Farm planning appeal. (included in Technical Appendix 8.1) 74 Discussed in Paragraph 8.9.8 below – these birds are not considered to be SPA birds 75 Discussed in paragraph 8.9.10 below – this species is not an SPA species


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Ornithology

GREENLAND GREATER WHITE-FRONTED GOOSE

8.9.5 As the Proposed Development is considered to have no impact on GWFG no cumulative assessment for this species has been included in the assessment.

WHOOPER SWAN

8.9.6 Cumulative impacts on whooper swan have been identified with the Dounreay to Mybster transmission line (0.78 birds per annum), Baillie wind farm (0.55 birds per annum), Reaster Farm (0.37 birds per annum) and Halsary wind farm (0.36 birds per annum) assessed to have the largest collision risks. The cumulative collision risk of 5.73 birds per annum consists of 2.75 % of the total whooper swan Caithness Lochs SPA population. Again, using the SNH commissioned population viability study76 removing 2.75 % of the SPA whooper swan population would decrease the yearly population increase by 3.58 %, meaning that the population would still be predicted to increase by 1.14 % per year. This adverse impact is of moderate magnitude, permanent and irreversible. However, the population of whooper swan would still be increasing albeit at a lower rate and so a significant impact is assessed to be very unlikely (6 – 10%).

GREYLAG GOOSE

8.9.7 Cumulative collision risk for greylag geese has been identified with Baillie Hill (2.94 birds per annum), Hill of Lybster (3.31 birds per annum), and Dounreay to Mybster transmission line (131 birds per annum), it is important to note however that the 131 birds per annum from Dounreay to Mybster transmission line was calculated with an avoidance rate of 99 %, and is therefore likely to be a gross overestimate. The Dounreay to Mybster transmission line also passes through Baillie wind farm and as such many, if not all, of the predicted collisions associated with that scheme were also predicted for the Proposed Development, i.e. they have been double counted. The overall cumulative collision risk for the species has been calculated to be approximately 155.94 birds per annum or approximately 1.71% of the SPA population. Whilst the greylag goose risk is low (1-5%) rather than negligible, this is in the context of a population which is increasing at a greater rate than the predicted cumulative impact and as such, the population would be expected to continue to grow and no ecologically significant impact is predicted.

HEN HARRIER

8.9.8 The cumulative schemes with the highest predicted impact on hen harriers are the Dounreay to Mybster transmission line (0.85 birds per annum), Strathy North (0.38 birds per annum) and Strathy Wood (0.11 birds per annum) and leading to a cumulative collision risk of 3.59 birds per annum77. These figures relate to cumulative sites with the potential to have an ornithological impact on the same SPA’s that the Proposed Development could have an impact on.

8.9.9 This represents a significant impact if assessed against the SPA hen harrier population (22.9 %). However, this figure is almost certainly an overestimate for two reasons. Firstly, this assessment considered all hen harriers seen during the surveys to be SPA birds when in reality, many if not all of them may be wider

76 Trinder, M. (2012). The Potential consequences of elevated mortality on the population viability of whooper swans in relation

to wind farm developments in Northern Scotland. 77 This includes data arising from other wind farms with a potential impact on the SPA population. This data, as presented in Technical Appendix 8.1 was compiled during the appeal process for Strathy South Wind Farm – June 2015.


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countryside birds as they were recorded mostly in the winter periods and over 3 km away from the nearest SPA. The wider countryside hen harrier population for Natural Heritage Zone Two Orkney and Northern Caithness is 324 birds and the cumulative impact of the Proposed Development and other projects would be just 1.27 %. Secondly, even if some of the birds are connected to the SPA, the SNH cumulative impact spreadsheet acknowledges that the calculated risk "doesn't take into account mitigation/compensation which would reduce the figures significantly." As such, the cumulative impact on hen harrier of the Proposed Development in combination with other projects is not considered to result in an ecologically significant impact.

GOLDEN PLOVER

8.9.10 The highest cumulative impacts on golden plover SPA population arise from the Dounreay to Mybster transmission line (9 birds per annum) and Hill of Lychrobbie (3.38 birds per annum) giving a cumulative collision risk of 28.58 birds per annum which is approximately 1.2 % of the SPA population and not considered to result in an ecologically significant impact.

PINK-FOOTED GOOSE

8.9.11 The cumulative impact on pink-footed goose is estimated to be 48.39 birds per annum. However, the species is not a qualifying interest species of any SPA in the vicinity of the Proposed Development and assessing a loss of 48.39 birds per annum with the approximately 200,000 birds that over winter in Scotland would give a loss of approximately 0.02 % per annum. As such no ecologically significant impact on the species from collision risk is predicted.

8.10 Summary

8.10.1 This chapter reports upon the ornithological impacts and effects of the Proposed Development. The baseline ornithological conditions were assessed in two phases; the first, a desk study of historical data sources and the second, targeted field surveys of important ornithological receptors identified in the desk study across a wide study area.

8.10.2 The methods and results of desk and field studies are reported for designated sites and specially protected species and species of conservation importance/concern. The area of the Proposed Development does not qualify as nationally or internationally important for any species of birds, however there are three SPAs in the vicinity.

8.10.3 Activity by geese and swans in the winter months and by wading birds and raptors in the summer months were the main areas of ornithological interest in the vicinity of the Proposed Development.

8.10.4 Without exception, no significant effects are predicted on the key ornithological receptors from the Proposed Development assuming that planned and designed mitigation is fully implemented.

8.10.5 Based on the assessment set out within this chapter, impacts from the Proposed Development on SPA qualifying interest species are not considered likely to affect the integrity of the designated sites. As a result no requirement for an Appropriate Assessment of the Proposed Development with regard to any of the designated sites has been identified.


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Ornithology

Summary of OHL Impacts

8.10.6 Table 8.7 summarises the potential impacts of the Proposed Development, as well as mitigation and residual impacts of the OHL.

Table 8.7: Summary of Potential Impacts of the Proposed Development, mitigation and Residual Impacts of the OHL

Receptor Potential Impact

Mitigation Proposed



Construction


Potential for direct or indirect impacts through: Habitat loss Disturbance

Pre-construction surveys Avoidance of construction in key locations at periods of high sensitivity Training and awareness raising of construction staff

Pre-construction protected species survey Ecological Clerk of Works to provide on-site training to construction staff Construction Environmental Management Document (CEMD) or Construction Environmental Management Plan (CEMP)

No ecologically significant Impact

Caithness and Sutherlands Peatlands SPA Species

Potential of direct or indirect impacts though: Habitat loss Disturbance




North Caithness Cliffs SPA Species

Potential for direct or indirect impacts though: Habitat loss Disturbance


Pre-construction protected species survey Ecological Clerk of Works to provide on-site training to construction staff Construction Environmental Management Document (CEMD)



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Mitigation Proposed



or Construction Environmental Management Plan (CEMP)

Wider Countryside Species

Potential for direct or indirect impacts though: Habitat loss Disturbance




Operation


Disturbance Collision Risk

Underground cable from Reaster to Gills Bay and Line marking at key locations from Fryster to Wester Olrig

Installed during construction

The Proposed Development would have a low impact on the whooper swan SPA population However, considering all cumulative sites this would likely have a medium impact with a minor to medium ecological significance

Caithness and Sutherland Peatlands SPA Species


Underground cable from Reaster to Gills Bay as well as line marking from Fryster to Wester Olrig

N/A Low impact on hen harrier SPA population with no ecologically significant impacts



N/A N/A No ecologically significant impacts


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Ornithology



Mitigation Proposed





Line marking and undergrounding would reduce collision risk for wider countryside species

Installed during construction

No ecologically significant impacts

Summary of Underground Cable Impacts

8.10.7 Table 8.8 summarises the potential impacts of the Proposed Development, as well as mitigation and residual impacts of the underground cable.

Table 8.8: Summary of Potential Impacts of the Proposed Development, mitigation and Residual Impacts of the Underground Cable

Potential Impact Potential Impact

Mitigation Proposed



Construction


Disturbance Avoidance of known feeding locations such as the GWFG using the fields west of the Proposed Development at Syster Pre-construction surveys Avoidance of construction in key locations at periods of high sensitivity Training and awareness raising of construction staff

Design layout of underground cable Pre-construction protected species survey Ecological Clerk of Works to provide on-site training to construction staff Construction Environmental Management Document (CEMD) or Construction Environmental Management Plan (CEMP)

Minor temporary disturbance near habitat used for feeding and loafing by GWFG east of Loch Heilen No ecologically significant impacts


Disturbance Pre-construction surveys Avoidance of construction in key locations at periods of high sensitivity Training and awareness raising of construction staff

Pre-construction protected species survey Ecological Clerk of Works to provide on-site training to construction staff Construction Environmental Management Document (CEMD)



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Mitigation Proposed



or Construction Environmental Management Plan (CEMP)









Operation


None N/A N/A No ecologically significant impacts






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Ornithology



Mitigation Proposed






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LT000022 9-1 Chapter 9:

Cultural Heritage and Archaeology

9 CULTURAL HERITAGE AND ARCHAEOLOGY

9.1 Introduction

9.1.1 This chapter considers the potential impacts on archaeology and cultural heritage interests (hereafter heritage assets) of the construction and operation of the Proposed Development. The specific objectives of the assessment are outlined below: • to identify the cultural heritage baseline within the study area;

• to assess the study area in terms of its archaeological potential;

• to consider the potential direct, indirect and cumulative impacts of the Proposed Development on heritage assets; and

• to identify measures, where appropriate, to mitigate any predicted significant adverse impacts and to assess residual impacts taking this mitigation into account.

9.1.2 This chapter and impact assessment (comprising a desk-based assessment and walk-over field survey) have been undertaken by CFA Archaeology Ltd, using information provided by Historic Scotland (HS) and The Highland Council Historic Environment Team (HET).

9.1.3 All field surveys were completed by suitably qualified archaeologists from CFA Archaeology Ltd.

9.2 Legislation and Policy Context

9.2.1 The primary planning guidance comprises Scottish Planning Policy (SPP1) supported by the Scottish Historic Environment Policy document (SHEP2) and Planning Advice Note (PAN) 2/20113 at national level, and, at the regional and local level, the Highland-wide Local Development Plan4 (adopted April 2012), The Highland Historic Environment Strategy, Supplementary Planning Guidance5 (January 2013), and the Caithness Local Plan6 (as continued in force) (April 2012). Further information on the relevant policy is considered in Chapter 5: Planning and Policy Context.


Scottish Planning Policy (2014)

9.2.2 Historic environment assets include those with statutory and non-statutory designations, as defined in SPP. Those relevant to the following assessment are: Scheduled Monuments, Listed Buildings, Conservation Areas, Inventory status

1 The Scottish Government (2014) Scottish Planning Policy, Edinburgh. 2 Historic Scotland (2011) Scottish Historic Environment Policy, Edinburgh. 3 Scottish Government (2011) Planning Advice Note 2/2011 Planning and Archaeology. 4 The Highland Council (2012) The Highland wide local Development Plan (adopted April 2012), Inverness: The Highland Council. 5 The Highland Council (2012) Highland Historic Environment Strategy, Interim Supplementary Planning Guidance. Inverness: The Highland Council 6 The Highland Council (2012) Caithness Local Plan (As Continued in Force) (April 2012) Inverness: The Highland Council, Planning and Development Service.


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Chapter 9: Cultural Heritage and Archaeology 9-2 LT000022

Gardens and Designed Landscapes (GDL) and other historic environment interests. There are no World Heritage Sites and no Historic Battlefields that would be affected by the Proposed Development.

Scottish Historic Environment Policy (2011)

9.2.3 This sets out the Scottish Ministers’ policies for the historic environment, and provides policy direction for Historic Scotland and a framework that informs the day to day work of a range of organisations that have a role and interest in managing the historic environment. Through the implementation of the SHEP, Scottish Ministers wish to achieve three outcomes for Scotland’s historic environment: that the historic environment is cared for, protected and enhanced for the benefit of our own and future generations; to secure greater economic benefits from the historic environment; and that the people of Scotland and visitors to Scotland value, understand and enjoy the historic environment.

Planning Advice Note (PAN) 2/2011: Planning and Archaeology (2011)

9.2.4 PAN 2/2011 advises that, in determining planning applications, planning authorities should take into account the relative importance of archaeological sites (Para 5). It also notes that in determining planning applications that may impact on archaeological features or their setting, planning authorities may on occasion have to balance the benefits of development against the importance of archaeological features (Para 6). The desirability of preserving a monument (whether scheduled or not) is a material consideration and the objective should be to assure the protection and enhancement of monuments by preservation in situ, in an appropriate setting. When preservation in situ is not possible, recording and / or excavation followed by analysis and publication of the results may be an acceptable alternative (Para 14).

Regional Policy

The Highland-wide Local Development Plan (HwLDP) (2012)

9.2.5 The following HwLDP policies are relevant to this assessment: • Policy 28: Sustainable Design. This states that the Council will support

development which promotes and enhances the social, economic and environmental well-being of the people of Highland.

• Policy 57 – Natural Built and Cultural Heritage. All development proposals will be assessed taking into account: the level of importance and type of heritage features, the form and scale of the development, and any impact on the feature and its setting.

Local Policy

Caithness Local Plan (As Continued in Force) (April 2012)

9.2.6 Whilst the HwLDP as discussed above now supersedes large parts of the Caithness Local Plan 2002, a parliamentary order has been made to retain elements of these plans prior to the adoption of the forthcoming Caithness and Sutherland Local Development Plan.

9.2.7 Through the Caithness Local Plan the Council aims to safeguard and enhance the cultural heritage of Caithness by protecting archaeological sites, landscapes, Listed Buildings, Conservation Areas and their settings (Para 8). General Policy PP3 states that the Council will presume against development, where there would be


LT000022 9-3 Chapter 9:


significant damage to heritage. In Paragraph 1.38 of the Local Plan the Council sets out its strategy for protection of the environment, which follows a hierarchical approach ranging from international sites through national sites to locally important sites. These have varying degrees of protection and development potential.

Other Guidance

Highland Historic Environment Strategy, Supplementary Planning Guidance (January 2013):

9.2.8 This sets out the Council’s approach to the protection of the historic environment to ensure that there is a proactive and consistent approach to its enhancement, protection and promotion.


9.3.1 Historic Scotland provided a scoping response on 20 February 2014 raising a number of heritage issues to be considered during the assessment process. A summary of the response is provided in Table 9.1.



Historic Scotland (Scoping response 20 Feb 2014)

HS raised concerns about the potential impact of the Proposed Development on four Scheduled Monuments, one Category A Listed Building and one GDL within the surrounding area (see below) and requested that the potential impact on these heritage assets should be assessed as part of the EIA. Scheduled Monuments • Tulloch of Shalmstry, broch (594) • Stemster Hill, chambered cairn (486) • Earney Hillock, chambered cairn (439) • Earl’s Cairn, chambered cairn (449)

Category A Listed Buildings • Castle of Mey (1797)

GDL • Castle of Mey GDL

The assessment of impacts upon the setting of these heritage assets should include visualisations showing views from the assets to the Proposed Development.

The indirect impacts of the Proposed Development on these heritage assets are assessed in Section 9.8. A list of cultural heritage visualisations is provided in Figures 9.3 to 9.6. Following reviews of the Proposed Development the section of OHL initially running from Lochend to Philips Mains has been replaced with an underground cable and there is no predicted visibility of the Proposed Development from Category A Listed Building Castle of Mey (1797) and Castle of Mey GDL (see Section Mitigation by Design).

The EIA assessment should consider the cumulative impacts of the Proposed Development in combination with others of a similar type in the vicinity.

The cumulative impacts of the Proposed Development are assessed in Section 9.9.


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Guidance

9.4.1 This assessment was conducted in accordance with the Chartered Institute for Archaeologists Code of Conduct7, Standard and Guidance for Historic Environment Assessment8 and The Highland Council Standards for Archaeological Work9. The assessment has been designed to comply with Section 3 (Survey) and Section 4 (Environmental Statements) of The Highland Council Standards for Archaeological Work.

The Study Area

9.4.2 The study area for consideration of potential direct impacts upon heritage assets comprised the area within the Limit of Deviation (LOD) for the Proposed Development. A detailed desk-based assessment was conducted for the Proposed Development, using a range of documentary, archival and bibliographic sources.

9.4.3 The LOD of the Proposed Development was surveyed in full. A gazetteer of heritage assets identified within the LOD of the Proposed Development is provided in Technical Appendices 9.1 and 9.2 (see details below) and the locations and extents of these heritage assets are shown on Figures 9.1a-9.1h).

9.4.4 Figure 9.1b indicates where survey was not possible due to landowner restrictions (at Achingills) and Figure 9.1c indicates where field survey was limited due to dense gorse bushes and conifer trees (at Durran).

9.4.5 The study area for consideration of potential indirect impacts upon the setting of cultural heritage assets uses a 10 km ZTV (bare ground and with screening) from the alignment of the Proposed Development. (Figure 9.2). Further explanation of the ZTV is included within Chapter 6: LVIA. A list of relevant assets identified within the ZTV and an assessment of the likely indirect impacts upon them resulting from the construction and operation of the Proposed Development, is presented in Technical Appendices 9.3 and 9.4.

Cultural Heritage Viewpoints

9.4.6 Four viewpoints (see Table 9.2 for details) to evaluate potential indirect impacts of the proposals on the setting of cultural heritage assets were identified in consultation with Historic Scotland (see Table 9.1 above for details). Table 9.2 provides details on the cultural heritage viewpoints.

7 Chartered Institute for Archaeologists (CIfA) (2014) ‘By-Laws: Code of Conduct’, Chartered Institute for Archaeologists, Reading 8 Chartered Institute for Archaeologists (CIfA) (2014) ‘Standard and guidance for historic environment desk-based assessment’, Chartered Institute for Archaeologists, Reading 9 The Highland Council (2012) The Highland Council Standards for Archaeological Work (March 2012), Inverness


LT000022 9-5 Chapter 9:


Table 9.2: Cultural Heritage Viewpoints

Asset no Asset name Status Viewpoint type and location

Figure no

439 Earney Hillock, chambered cairn

Scheduled Monument

Wireline from cairn

Figure 9.3

449 Earl’s Cairn, chambered cairn

Scheduled Monument

Wireline from cairn

Figure 9.4

486 Stemster Hill, chambered cairn

Scheduled Monument

Wireline from cairn

Figure 9.5

594 Tulloch of Shalmstry broch

Scheduled Monument

Wireline from broch

Figure 9.6

Desk-based Study

9.4.7 A detailed desk-based assessment was conducted for the study area using a range of documentary, archival and bibliographic sources. Up-to-date information was obtained from appropriate sources, including the ZTV, on the locations and extents of heritage assets with statutory protection and non-statutory designations within the study area.

9.4.8 Details of the locations and extents of Scheduled Monuments, Listed Buildings, Inventory Garden and Designed Landscapes, Conservation Areas and Historic Battlefields were downloaded, in GIS, from the Historic Scotland Data Warehouse10.

9.4.9 Information on known heritage assets within the LOD of the Proposed Development was obtained from The Highland Council Historic Environment Record (HER) in March 2014.

9.4.10 Additional information on the character and condition of known archaeological sites and features within the LOD of the Proposed Development was obtained from the Royal Commission on the Ancient and Historical Monuments of Scotland (RCAHMS) Database11.

9.4.11 Ordnance Survey maps (1st and 2nd Edition maps12) and other historic maps held by the Map Library of the National Library of Scotland were examined to provide information on sites or features of potential historic environment interest and on historic land-use development within the LOD of the Proposed Development.

9.4.12 An assessment was made of vertical aerial photograph collections held by the RCAHMS. Sorties dating from 1946 were examined for the LOD of the Proposed Development. In addition, modern aerial photographic imagery available through GoogleEarthTM and BingTM was examined.

10 Historic Scotland (2014) GIS downloaded, available at http://hsewsf.sedsh.gov.uk/gisdl.html (accessed in March 2014). 11 RCAHMS (2014) Royal Commission of Ancient and Historic Monuments Database (PASTMAP) available from: http://jura.rcahms.gov.uk/PASTMAP/start.jsp (accessed in February/March 2014 & April 2015). 12 National Library of Scotland, Map images (Ordnance Survey 1st and 2nd Edition maps) available from: map.nls.uk (accessed March 2014 & April 2015)


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9.4.13 Historic Land-Use Assessment Data for Scotland (HLAMap)13 was consulted for information on the historic land-use character across the LOD of the Proposed Development.

9.4.14 The Scottish Palaeoecological Database (SPAD)14 which records the distribution of known palaeoenvironmental sites across Scotland was consulted for information on such sites within the LOD of the Proposed Development. The resource provided no specific relevant information.

9.4.15 Bibliographic and documentary sources (Jolly 1791-9915, Jolly 1834-4516, Wood 201117, SUAT 200418, Humphreys et al. 200919) were consulted to provide additional information on the cultural heritage resource and the historic background to the area in general.

Field Survey

9.4.16 An initial walk-over field survey of the LOD of the Proposed Development was undertaken 25–28 March 2014. Further field survey was carried out 22–23 April 2015 following variations to the Proposed Development (see Chapter 4: Routing Study and Alternatives. The aims of the field survey were as follows: • to assess the baseline condition of the known heritage assets identified

through the desk-based study; and

• to identify any further features of cultural heritage interest not detected from the desk-based study and to assess the potential for the LOD to contain currently unrecorded, buried archaeological remains.

9.4.17 Identified heritage assets were recorded on pro-forma monument recording forms and by digital photography, and their positions (and where appropriate their extents) were logged using a Global Positioning System (GPS). No intrusive archaeological works have been carried out as part of this assessment.

9.4.18 Site visits to heritage assets within the ZTV were also carried out in March 2014, to assess the character and sensitivity of the settings of those assets and to assess the likely impacts of the Proposed Development on those settings. Site visits focused on heritage assets closest to the LOD of the Proposed Development and those specifically identified as requiring assessment by Historic Scotland. Where access was difficult or denied, publicly accessible locations as close as possible to the receptor were sought as a basis for assessment. Factors considered in the assessment of the setting undertaken during the field visit include: • the location and orientation of the asset;

• important views of, or from, the asset (e.g. principal façades of Listed Buildings);

13 RCAHMS (2014) Historic Land-Use Assessment for Scotland (HLAMap) available from: http://rcahms.gov.uk (accessed in March 2014 & April 2015). 14 Coles, G.M., Gittings, B.M., Milburn, P. and Newton, A.J. (1998). Scottish Palaeoecological Archive Database available from: http://xweb.geos.ed.ac.uk/~ajn/spad/ (accessed March 2014 & April 2015). 15 Jolly, Rev. Mr T (1791-99), The Statistical Accounts of Scotland, Parish of Dunnet, No XVIII, p243-258 16 Jolly, Rev. Mr T (1834-45), The New Statistical Accounts of Scotland, Parish of Dunnet, Vol 15, p34-48 17 Wood, J. (2011) Caithness Electricity Distribution Reinforcement – Dounreay – Gills Bay 132kV (Revised Route): Cultural Heritage Baseline Assessment, Highland Archaeology Services Ltd, Report no: HAS110803. 18 SUAT (2004) Archaeological Component Proposed Wind Farm at Schoolary Caithness, Highland, Ref: NDSH/CAM/SLO1. 19 Humphreys, P. McCullagh, C. & Wood, J. (2009) Hilliclay Stemster Water Main Replacement, Watching Brief, Highland Archaeology Services Ltd, Report no. HAS090101.


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• the importance, if applicable, of designed settings; and

• any obvious views or vistas.

Method of Assessment – Assessment of Direct (Construction) Impacts

9.4.19 The type of impacts on heritage assets which might result from the Proposed Development have been assessed in the following categories: • Direct, where there may be a physical impact on an asset caused by the

construction of the Proposed Development. Direct impacts tend to have permanent and irreversible adverse effects upon cultural heritage remains.

• Indirect, where elements of the Proposed Development could affect the setting of heritage assets present in the vicinity.

• Cumulative, where the Proposed Development in conjunction with other developments in the surrounding landscape could affect the setting of heritage assets present in the vicinity.

9.4.20 Impacts have been assessed in terms of their magnitude (Table 9.4), permanence (permanent/ temporary), reversibility, and nature (adverse/ neutral/ beneficial).

9.4.21 Beneficial impacts are those that contribute to the value of an asset through enhancement of desirable characteristics or the introduction of new, positive attributes. Neutral impacts occur where the development can be accommodated comfortably by the receiving environment while neither contributing to nor detracting from the value of the asset. Adverse impacts are those that detract from the value of the asset through a reduction in or disruption of valuable characteristics, or in the introduction of new inappropriate characteristics.

Relative Importance of Heritage Assets

9.4.22 Heritage assets represent a non-renewable resource that are often fragile and suffer from constant attrition, from both natural and human causes. The assessment of importance of heritage assets reflects the relative weight given to them in the SHEP and SPP documents as discussed in section 9.2 above.

9.4.23 Table 9.3 summarises the relative importance of those types of heritage asset relevant to this study.

Table 9.3: Importance of Cultural Heritage Assets

Heritage Importance Definition

National/International Assets of national and international importance, including: • Scheduled Monuments; • Category A Listed Buildings; and • Inventory status Gardens and Designed Landscapes.

Regional Assets of regional importance, including: • Archaeological assets of distinctive regional importance; • Category B Listed Buildings; and • Conservation Areas.

Local Assets of local importance, including: • Archaeological assets of local importance;


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Table 9.3: Importance of Cultural Heritage Assets

Heritage Importance Definition • Category C Listed Buildings; and • Unlisted buildings and townscapes with local (vernacular)

characteristics.

Lesser Assets of little or no importance, including: • Unlisted buildings or minor historic or architectural interest; and • Poorly preserved examples of particular types of features.

Magnitude of Construction (Direct) Impacts

9.4.24 Criteria for assessing the magnitude of direct (construction) impact, which measures the degree of change to the baseline condition of the heritage asset that could result from the construction of one or more elements of the Proposed Development, are presented in Table 9.4.

Table 9.4: Magnitude of Physical (Construction) Impacts

Level of magnitude Definition

High A total or fundamental change to the baseline condition of the asset, leading to total or major alteration of character.

Medium A material, partial alteration of character leading to loss of one or more key elements of the site.

Low Slight, detectable alteration of the baseline condition of the asset.

Imperceptible A barely, distinguishable change from baseline conditions.

Significance of Construction (Direct) Impacts

9.4.25 The importance of the heritage asset, defined in Table 9.3, and magnitude of the predicted impact (Table 9.4) are used to inform the professional judgement of the likely significance of the direct impact. Table 9.5 summarises the criteria for assessing the likely significance of a direct impact.

9.4.26 Major and moderate direct effects are considered to be ‘significant’ in the context of the EIA Regulations. Minor and negligible effects are considered to be ‘not significant’.

Table 9.5: Significance of Impacts

Magnitude of Impact ▼

Heritage Importance of Asset ►

National/International Regional Local Lesser

High Major Major Moderate Minor

Medium Major Moderate Minor None

Low Moderate Minor None None

Imperceptible Minor None None None


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Assessing Indirect (Operational) Impacts on Setting

9.4.27 Historic Scotland’s guidance document ‘Managing Change in the Historic Environment: Setting’ (Historic Scotland 201020) notes that “setting should be thought of as the way in which the surroundings of a historic asset or place contribute to how it is experienced, understood and appreciated. Setting often extends beyond the immediate property boundary of a historic structure into the broader landscape”. The guidance also suggests that if a proposed development is likely to affect the setting of a heritage asset, an objective, written assessment should be prepared by the applicant to inform the decision-making process. The conclusions drawn should take into account the significance of the historic asset and its setting and attempt to quantify the extent of any detrimental impact. The methodology and level of information should be tailored to the circumstances of each case.

9.4.28 The guidance recommends that, for each heritage asset where a potential impact on setting has been identified, the assessment of possible impacts should adopt a four-stage approach: • identification of the characteristics of the setting of the asset;

• assessment of the sensitivity of that setting;

• identification of how the presence of the Proposed Development would affect that setting (magnitude of impact); and

• assessment of significance of effect.

Criteria for Assessing Sensitivity of Setting

9.4.29 Sensitivity of setting has been assessed by considering two factors: • the relative weight which statute and policy attached to the heritage asset and

its setting (Table 9.3); and

• the degree to which the baseline setting contributes to the understanding and/or appreciation, and hence value, of the heritage asset (Table 9.6).

Table 9.6: Contribution of Setting to Understanding and Appreciation of a Cultural Heritage Asset

Contribution of setting

Definition

High A setting which makes a strong positive contribution to the understanding and / or appreciation of the siting and / or historical / archaeological / architectural context of a heritage asset. e.g. a prominent topographic location; surroundings that include related monuments in close association; surroundings that are believed to be little changed from those when the asset was created.

Moderate A setting which makes some positive contribution to the understanding and / or appreciation of the siting and / or historical / archaeological / architectural context of a heritage asset. e.g. surroundings that complement the siting and appearance of an asset such as the presence of a feature of the rural past within a more recent farming landscape containing little or no urban or industrial development.

20 Historic Scotland (2010) ‘Managing Change in the Historic Environment: Setting’, Edinburgh.


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Table 9.6: Contribution of Setting to Understanding and Appreciation of a Cultural Heritage Asset

Contribution of setting

Definition

Low A setting which makes little positive contribution to the understanding and / or appreciation of the siting and / or historical / archaeological / architectural context of a heritage asset. e.g. where surroundings only partially complement the siting and appearance of an asset, such as the presence of a feature of the rural past within a partly urbanised or industrialised landscape.

Negligible A setting which does not contribute positively to the understanding and / or appreciation of the siting and / or historical / archaeological / architectural context of a heritage asset. e.g. immediate surroundings, such as of a commercial coniferous single species woodland or an industrial development, that are not relevant to understanding the context of the asset.

9.4.30 The two criteria (Table 9.3 and Table 9.6) are combined to assess the overall sensitivity of setting, as set out in Table 9.7.

Table 9.7: Sensitivity of Setting of an Asset

Heritage Importance ▼

Contribution of Setting ►

High Moderate Low Negligible

National/International High High Medium Low

Regional High Medium Low Low

Local Medium Medium Low Low

Criteria for Assessing Magnitude of Impacts on Setting

9.4.31 Where it has been determined that the setting of an asset is such that there is no potential for it to be affected by the presence of the Proposed Development the asset is not considered further in the assessment (i.e. no visibility as indicated by the Bare-Earth ZTV). For the remaining assets, the magnitude of impact on setting has been assessed according to the thresholds set out in Table 9.8.

Table 9.8: Magnitude of Impacts on Setting

Magnitude of Impacts on Setting

Definition

High A fundamental material impact obviously changing the surroundings of a heritage asset, such that its baseline setting is substantially or totally altered.

Medium An impact discernibly changing the surroundings of a heritage asset, such that its baseline setting is partly and materially altered.

Low A slight, but detectable impact that does not materially alter the baseline setting of the heritage asset.

Imperceptible A very slight and barely distinguishable change from baseline conditions.


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Criteria for Assessing Significance of Effects on Setting

9.4.32 The significance of an impact depends on both the magnitude of impact and the sensitivity of the setting of the asset.

9.4.33 Table 9.9 presents the matrix that was used to inform the determination of the significance of effects on setting.

Table 9.9: Significance of Impact on Setting

Magnitude of Impact ▼

Sensitivity of Setting ►

High Medium Low

High Major Major Minor

Medium Moderate Moderate Minor

Low Minor Minor None

Imperceptible None None None

Cumulative Assessment

9.4.34 The assessment of cumulative impacts on the cultural heritage is based upon consideration of the impacts of the Proposed Development on the setting of heritage assets with statutory designations within 10 km of the OHL in addition to the likely impacts of other cumulative developments of similar type (Chapter 3: EIA Methodology, Figure 3.1). The assessment takes into account the relative scales (i.e. size, number of turbines etc.), of the various developments, their distance from the affected asset, and the potential degree of visibility from the assets of the various developments.


9.4.35 The significance of impacts is classified as Major, Moderate, Minor and None, as defined in Tables 9.5 and 9.9. Major and moderate effects are considered to be ‘significant’ in the context of the EIA Regulations. Minor and negligible effects are considered to be ‘not significant’.

Table 9.10: Significance Criteria

Level of Significance

Definition

Major A change to the fabric or setting of a heritage asset that leads to a substantial environmental effect.

Moderate Changes to the fabric or setting of a heritage asset that lead to a material environmental effect.

Minor Changes to the fabric or setting of a heritage asset that lead to a detectable but non-material environmental effect.

None Changes to the fabric or setting of a heritage asset that lead to, at most a negligible environmental effect.


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9.5.1 In total, 55 heritage assets have been identified within the LOD of the Proposed Development. The location and extents of these assets are shown on Figures 9.1a-9.1h. Technical Appendices 9.1 (OHL elements) and 9.2 (underground cable elements) provides gazetteer information on their character and baseline condition.

9.5.2 Numbers in brackets and in bold in the following text, refer to asset numbers depicted on Figures 9.1a-9.1h and listed in Technical Appendices 9.1 and 9.2. Following the initial field survey, carried out in March 2014, the LOD of the Proposed Development was revised (see Chapter 4: Route selection and Alternatives). A number of cultural heritage assets that were originally located within the initial Proposed Development LOD now lie outside it, and additional heritage assets were identified. The heritage assets no longer relevant have been removed from Appendices 9.1 and 9.2 (now noted as ‘number not used’); although, for ease, the original numbers given to the remaining sites, still located within the LOD of the Proposed Development have been kept.

9.5.3 There are no Scheduled Monuments or Listed Buildings within the LOD of the Proposed Development and no part of the Proposed Development would lie within a Conservation Area, Historic Battlefield or Inventory Garden and Designed Landscape.

9.5.4 Analysis of the ZTV (Figure 9.2) indicates that there would be theoretical visibility of one or more components of the Proposed Development from 39 Scheduled Monuments; one Category A Listed Building; 18 Category B Listed Buildings; 13 Category C Listed Buildings; and one Conservation Area.

Heritage Assets within the LOD of the Proposed Development

9.5.5 Thirty-seven heritage assets have been identified within the LOD of the Proposed Development. The majority of these features are associated with post-medieval settlement and agrarian activities, although one potentially prehistoric site, the former location of a possible broch, has been recorded at Hilliclay. The Proposed Development principally crosses areas of pasture or arable fields that have been ploughed and substantially improved from the 19th century onwards.

Potential Prehistoric Settlement

9.5.6 The Ordnance Survey 1st Edition map depicts the ‘site of a Pict’s House’ (23), possibly the remains of a later prehistoric broch, within an improved pasture field at Hilliclay. The upstanding remains of this structure were removed during the mid-19th century (Ordnance Survey Name book, 187221) and no surface trace of the site now survives. A watching brief was carried out during ground breaking works for a water main renewal in 2009 (Humphreys et al., 200922) as it passed the ‘broch’ site; no features or finds were uncovered at this time. No remains of the ‘broch’ are visible today and it is unknown what the condition of survival of any buried remains might be. As the possible remains of a prehistoric settlement, the site is considered to be of unknown, but potentially of regional, importance.

21 Ordnance Survey Object Name Books (1872) Book no1, p 6. 22 Humphreys, P. McCullagh, C. & Wood, J (2009) Hilliclay Stemster Water Main Replacement Watching Brief, Highland Archaeology Services Ltd, Ref no: HAS090101.


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Medieval or Later Settlement

FARMSTEAD AND OTHER BUILDING REMAINS

9.5.7 Nine farmsteads (11, 16, 24, 27, 72, 77, 80 and 84-85) along with four other small settlements (possible farm worker or tenant farmer cottages and associated structures) (19, 38, 41 and 74) are recorded on historic maps (Ordnance Survey 1st

and 2nd Edition maps) at Weydale (11) Achingills (16 and 19), Meikle Burn (24), Tows (27), Round Hill (38), Hill View (41), Hall of Durran (72), Hoy (74, 77), Tofts of Tain (80) and Greenland (84-85).

9.5.8 Three of these farmsteads - Weydale Farm South (11), Hall of Durran (72) and Hoy (77) - are still occupied and form part of working farms and are of local heritage importance.

9.5.9 No upstanding remains of two of these sites – buildings (38 and 74) – were visible during the field survey. The areas in which these buildings once stood have been ploughed and are now improved pasture fields. It is probable that the structures were demolished and largely removed to accommodate modern agricultural practices. It is possible that some buried remains may still be preserved at these locations, although it is likely that any building foundations have been disturbed or removed during ploughing/land improvement activities. The buildings are considered to be of lesser heritage importance.

9.5.10 Five farmsteads (24, 27, 80 and 84-85) and a building with associated enclosure (41) survive as ruins located in what are now improved pasture fields. The ruins survive in varying conditions: • The farmsteads at Meikle Burn (24), Tows (27) and Tofts of Tain (80) are

generally well-preserved with each having a building standing to roof height.

• Only the low-relief turf covered footings of the farmsteads at Greenland (84-85) survive, although the remains of a corn-drying kiln attached to the north-western end of the main farm building at farmstead (85) does survive to over 1 m high.

• All that survives of the building (41) at Hill View is the tumbled footings of the west wall and the north gable end.

9.5.11 All of these structures are shown on the Ordnance Survey 2nd Edition as either completely roofed or partially roofed suggesting that they were all probably still in use, in varying degrees, during the early-20th century. Examination of vertical aerial photographs from 1946 indicates that many of the buildings were unroofed ruins by that date and the evidence would appear to show that they were generally abandoned by at least the late 1940s. Upstanding remains of the buildings still survive (24, 27, 41, 80 and 84-85) and these are considered to be of local heritage importance.

9.5.12 The unroofed remains of a farmstead (16) and building (19) are visible on modern aerial photography (GoogleEarthTM). Both of these settlements are depicted on the Ordnance Survey 1st and 2nd Edition maps. By the 2nd Edition building (19) is shown as unroofed suggesting that it had been abandoned by that time. The assets could not be visited during the field survey and the current baseline conditions of the sites are unknown. Given that the ruins of both settlements are visible on modern aerial photography it is likely that some remains of these two


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structures survive; if this is indeed the case then they are probably of local heritage importance.

9.5.13 The HER records the presence of Weydale school and school house (9) forming part of Weydale village. Both buildings are now in residential use and occupied. They are of local heritage importance.

FIELD SYSTEMS AND OTHER AGRARIAN FEATURES

9.5.14 Much of the land around Thurso and Castletown comprises rectangular enclosed fields that were substantially improved during the 19th century (Ordnance Survey maps and HLAMap) and little survives of any earlier field systems within these areas. Roy (1747-5523) depicts the area around Thurso and Castletown as unenclosed cultivated land indicating that the area was being cultivated from at least the mid-18th century.

9.5.15 Field survey recorded the presence of only two irregular spreads of clearance stones (36 and 78) dumped at the edge of improved/semi-improved pasture fields, the stone being cleared from the fields to improve the grazing land. These are likely to be of post-medieval date and are considered to be of lesser heritage importance.

9.5.16 In addition, short sections of former field banks (73 and 79), surviving as low-relief turf and stone banks were identified at the edges of rough/improved pasture fields. These are likely former field boundaries and are of lesser heritage importance.

PONDS AND ASSOCIATED FEATURES

9.5.17 Three ponds (12, 33 and 39), along with associated features (i.e. dams, sluice and wells), are depicted on the Ordnance Survey 1st and 2nd Edition maps at Weydale Farm South, Wester Olrig Farm and south of Valhalla respectively. All of the ponds are still visible as dried out hollows and are no longer in use. Two of the ponds (33 and 39) are generally poorly preserved. Fragments of a drystone culvert (or lade) and sluice associated with pond (12) still survive at Weydale Farm South, along with a short length of revetment wall defining the western edge of the former pond. The ponds were probably a source of water for the farmsteads and probably powered threshing machines or mills originally forming part of the 19th century farmsteads. Mercer (197824) suggested that a lade originally ran from pond (33) underground to the mill at Wester Olrig Farm in the north-west. No surface remains of the lade were recorded during the field survey, but below surface remains may still survive within the LOD of the Proposed Development. Given the preservation of some elements of the sluice and culvert (lade) at Weydale Farm South (12) the pond and associated elements are considered to be of local heritage importance. The other ponds (33 and 39) which are only poorly preserved are considered to be of lesser heritage importance.

Former Quarries

9.5.18 Nine former quarries (21, 34, 40, 43-44, 71, 75-76 and 82) are depicted on the Ordnance survey 1st and 2nd Edition maps between ‘Achingills’ and ‘Greenland’. The quarries tend to be located at what are now the edges of improved pasture fields and close to farmsteads. They probably date to the 18th/19th century and

23 Roy, W (1747-55) Military Survey of Scotland. 24 Mercer, J. (1978) Correspondence from 1987 relating to Ledmore Aare, Sutherland Survey 1978, held by the RCAHMS.


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were used as a source of stone and gravel to provide building material for farm buildings and field walls in the local vicinity. The majority of the quarries still survive, although in varying conditions of preservation. Three of them are visible as turf-covered depressions (21, 40 and 43) within improved fields, while four survive as water-filled hollows (34, 44, 76 and 82). Two of the quarries (71 and 75) have been filled with modern rubbish. The quarries are of lesser heritage importance.

Miscellaneous

9.5.19 The HER records that a photographic record was produced of an old farm cottage located at Weydale Farm South (10), prior to its demolition; nothing now survives of the building and the site is of lesser heritage importance.

9.5.20 Field survey recorded that the remains of a trackway (15) run from the public road at South Weydale Cottage, in the west-south-west, for 700 m to the ENE, before petering out in an improved pasture field. It is visible as a gorse-covered holloway with the partial remnants of turf and stone banks visible on either side. It may have once formed the access to a now unnamed ruined farmstead located just north-east of the east-north-east end of the trackway. It is of lesser heritage importance.

9.5.21 The HER records that two ‘Old limekilns’ (17) are depicted on the Ordnance Survey 1st Edition map at Achingills within in an area of quarrying, but are not shown on the Ordnance Survey 2nd Edition map. The faint outline of the area of quarrying is visible on modern aerial photography (GoogleEarthTM) on the edge of a now flat improved pasture field, but there are no obvious remains of the kiln. Access to this area was refused during the field survey and the current baseline condition of the kilns is unknown.

9.5.22 One well (18) is shown on the Ordnance Survey 1st Edition map at Achingill but not depicted on the Ordnance Survey 2nd Edition map suggesting that it had gone out of use by the early-20th century. Access to this area was refused during the field survey and the current baseline condition of the well is unknown. Wells were features used for short periods of time and generally with no formal structure; the example here is considered likely to be of lesser heritage importance.

9.5.23 Two areas of peat cutting at Hilliclay (25) and Moss of Greenland (45) are visible on vertical aerial photographs dating from 194625. Nothing now survives of the peat cuttings at Hilliclay (25), as this area has been ploughed and is now an improved pasture field. The faint outlines of former peat cutting areas are visible at Moss of Greenland (45), although this area appears no longer to be used as a source of peat. Both former peat cutting areas are considered to be of lesser heritage importance.

9.5.24 The HER records the presence of a farmstead (HER Ref no: MHG18843) at 32550, 96620, no remains of the farmstead were identified at this location during the field survey; the building remains were noted instead c.150 m to the north-east at 325603, 966275 and outside the study area.

25 Vertical Aerial Photographs, Date: 09.10.1946, Sortie: CPE/UK/0185, Library Reference: B_0140, held by the RCAHMS.


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Archaeological Potential

9.5.25 The landscape in this area consists principally of improved pasture and arable fields surrounding a number of farmsteads, although a small area of wet moorland/boggy ground is present at Moss of Greenland.

9.5.26 Examination of historic maps and 1st and 2nd Edition Ordnance Survey maps in conjunction with vertical aerial photographs (from 1946 and modern aerial photography (GoogleEarthTM) shows that the land has been principally improved since the 19th century.

9.5.27 Analysis of the HER records a number of prehistoric sites close to the LOD of the Proposed Development. These sites include: • the ruins of an Iron Age broch at Shalmstry (MHG164), approximately 850 m

to the west;

• former broch site (23, MHG1784), present within the OHL LOD for the Proposed Development;

• long cairn near Meikle Burn (MHG1786), 300 m to the south;

• a large lithic scatter (MHG 51542) uncovered at Stemster during a watching brief for water mains replacement work in 2009 (Humphreys et al. 2009), 500 m south;

• a cluster of prehistoric (Neolithic/Bronze Age) burial cairns at Sordale, including MHG2364, MHG1783, MHG1775 and MHG1776, approximately 1 km to the south;

• remains of a broch at Ha’ of Durran (MHG1785), 300 m to the south; and

• a possible Broch site at Hoy (MHG19477), approximately 800 m to the south-east.

9.5.28 Many of these features and artefacts no longer survive as in situ remains. However they indicate that the area between Weydale and Round Hill has been a focus for settlement and activity from the early prehistoric periods onwards. The locations of the various recorded sites does suggest that there is a moderate potential for further hitherto unknown buried remains to survive within this section of the LOD of the Proposed Development.

Heritage Assets within the LOD for the Underground Cable elements of the Proposed Development

9.5.29 For ease of discussion this section has been split into the following two sections: • Underground cable LOD between Thurso Substation and Weydale; and

• Underground cable LOD between Moss of Greenland and Gills Bay Substation.

Underground cable LOD between Thurso Substation and Weydale

9.5.30 Four heritage assets have been identified within this section of Proposed Underground Cable LOD that runs between Thurso substation and Weydale. The majority of these features are associated with post-medieval agrarian activities including former building footings, areas of cleared stone and former quarries. Little survives within this section of the Proposed Underground Cable LOD; the area comprises principally flat pasture and arable fields that have been substantially improved from the 19th century onwards.


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FARMSTEAD REMAINS

9.5.31 The remains of a former farmstead (13), surviving as a small grass-covered hillock, were identified just south of Weydale Farm South in an area of improved pasture. The farmstead is shown as comprising two rectangular buildings and an enclosure on the Ordnance Survey 1st Edition map, but is not depicted on the 2nd Edition map (190626) suggesting that the site had been abandoned by that date. Today little survives of the buildings; the most northerly building is visible only as low turf-covered footings, while no upstanding remains of the other is visible, nevertheless a pile of stone at the location of this former building suggests that there may be potential for buried remains to survive just below the turf. The former enclosure is only evident by a slight rectangular grass-filled hollow; no visible upstanding remains survive. The farmstead ruins are considered to be of local heritage importance.

AGRARIAN FEATURES

9.5.32 Field survey recorded an area of cleared stone (4) situated on the edge of an improved pasture field. The stone was likely cleared from the field to help improve grazing or to aid ploughing. It is likely of lesser importance.

QUARRIES

9.5.33 One quarry site (3a-b), comprising two quarries, is depicted on the Ordnance Survey 1st Edition map and annotated as ‘Old Quarries’, suggesting that the site was no longer in use by the mid-19th century. The quarry site has been removed by ploughing and only a slight turf-covered hollow is visible at the former location of one of the quarries (3b). The site was probably utilised as a source of stone for building farmsteads and field walls in the immediate locale; the quarry site is of lesser heritage importance.

SECOND WORLD WAR STRUCTURE

9.5.34 The HER records that a small artillery armament (5) was located at Shalmstry in 1940 as part of the Second World War coastal defences. Nothing now survives of the battery; the former military site is now located in an improved pasture field and is of lesser heritage importance.

ARCHAEOLOGICAL POTENTIAL

9.5.35 The landscape crossed by the underground elements of the Proposed Development, between Thurso Substation and Weydale, consists principally of improved pasture. Examination of historic maps (1st and 2nd Ordnance Survey maps) in conjunction with vertical aerial photographs (from 1946 onwards and modern aerial photography (GoogleEarthTM) shows that the land has been improved since the 19th century.

9.5.36 The HER records several prehistoric sites particularly concentrated along the River Thurso valley and close to this section of the Proposed Underground Cable LOD. These recorded sites include: • the ruins of an Iron Age broch (settlement) at Shalmstry (MHG164),

approximately 200 m to the west;

26 Ordnance Survey 2nd Edition (1906) Caithness, Sheet 011.08, 25 inch to 1 mile.


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• the former site of a broch at Whitefield (MHG1465) and the remains of a further broch at Giese (MHG1771), both 1 km to the west;

• a prehistoric cist burial with remains of a cremation urn uncovered at Glengolly in the late 1860s (MHG39799), 1.5 km to the north-west;

• a number of hut-circles surviving at Skinnet, near the floodplain of the River Thurso (MHG701 and MHG1779), approximately 2 km to the south-west; and

• a cluster of prehistoric (Neolithic/Bronze Age) burial cairns at Sordale, including MHG2364, MHG1783, MHG1775 and MHG1776, approximately 2 km to the south.

9.5.37 There has been a settlement at Thurso since at least the 12th century and Roy’s map of 1747-5527 shows several farmsteads (or townships) surrounded by cultivated land present to either side of the River Thurso, many of which are likely to have earlier (medieval/Norse) origins.

9.5.38 All of this indicates that the River Thurso valley has been significantly settled from the early prehistoric periods onwards. It is considered on this basis that there is a moderate potential for further buried archaeology to survive within the LOD of the underground cable elements of the Proposed Development.

Underground cable between Moss of Greenland and proposed Gills Bay Substation

9.5.39 Sixteen heritage assets have been identified within this section of LOD of the Proposed Development that runs between Moss of Greenland and proposed Gills Bay substation.

9.5.40 The majority of the features identified along this section of the LOD of the Proposed Development are associated with post-medieval (or earlier) agrarian activities including the remains of former farmsteads and associated field systems, shieling huts and a former mill.

FARMSTEADS AND BUILDINGS

9.5.41 A building (56) and a farmstead (86) are depicted on the Ordnance Survey 1st Edition map close to ‘Syster’ and ‘Lochend’ respectively. Building (56) is shown as partially unroofed on the 1st Edition map and the farmstead is depicted as unroofed, indicating that both were probably not occupied by the late 19th century. No upstanding remains of either the building (56) or the farmstead (86) survive; the areas in which they were previously located have been ploughed and now form parts of improved pasture field. The building and farmstead are both considered to be of lesser heritage importance.

9.5.42 Field survey identified what maybe the poorly preserved remains of a small horse-shoe shaped structure on the edge of an improved pasture field (83). The exact function of the structure is not known, but it may once have been a small store associated with a building present 25 m to the north of the structure (84) and is considered to be of local heritage importance.

SHIELING HUTS

9.5.43 Field survey recorded what may be the poorly preserved remains of three shieling huts (57a-c) located in an area of moorland (Grottistoft Moss) just west of the Link

27 Roy, W 1747-55 Military Survey of Scotland


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Burn. Little now survives of the shieling huts; the best-preserved (57a) is visible as a slight rectangular hollow, defined by much denuded turf banks, on a grassy knoll and immediately next to a former burn. The other two possible shieling huts are very poorly preserved and visible on small knolls; these structures were extremely vestigial and visible only as slight sub-circular grass-covered platforms.

9.5.44 The HER records that an area of possible former shieling land (61) (summer grazing area) is annotated as ‘Shielton’ on the Ordnance Survey 1st Edition map close to the Burn of Ormigill. No visible evidence for any possibly related features (such as shieling huts, enclosures or storage structures) were noted specifically in this area, although these could have been semi-permanent or temporary turf built structures that may not leave any physical remains. The remains of possible shieling huts (57a-c) were recorded around 500 m southwest of ‘Shelton’ suggesting that some of this area was likely given over to summer pasture activities.

9.5.45 Shielings were summer sites associated with grazing of livestock when the animals, principally cattle, were taken out to fresh grazing for a number of weeks. They are usually considered to be of medieval or later date, although some recently excavated huts have been demonstrated to have prehistoric origins (Gilmour & Church 200228, Carter et al 200529). Improved farming practices in the 18th and 19th century effectively ended the customary use of the shielings. The shieling hut remains recorded at Grottistoft Moss (57a-c) are probably the remnants of pre-improvement agrarian structures and, although generally poorly preserved, are considered to be of local heritage importance.

CORN DRYING BARN (OR MILL)

9.5.46 A long, unroofed, rectangular building (58a), annotated ‘Old corn mill’ is depicted on the Ordnance Survey 1st Edition map suggesting that the mill had been abandoned by the late-19th century. The ruins of the building still survive within an area of rough grazing at ‘Grottistoft Moss’ where the turf-covered footings of the building are visible, standing on a slight terrace at the end of an unnamed burn. The building is divided into at least three compartments and the remains of a corn drying kiln are visible set into the north-west end of the building, suggesting that the structure is a corn drying barn, which may have been associated with a now ruined farmstead at Syster to the south-west. A fragment of turf and stone bank (58b), possibly the remains of an early enclosure associated with the building, is visible just west of the building. The mill remains are generally well preserved and of local heritage importance.

POSSIBLE FIELD KILN

9.5.47 Field survey recorded what may be the remains of a kiln (60) located in an area of moorland (Grottistoft Moss). The structure survives as a low-relief turf-covered knoll that is hard to distinguish, but measures approximately 5.5 m in diameter, and appears to have a slight circular hollow at its centre. The structure is poorly preserved and on the basis of present knowledge it is considered to be of no more than local heritage importance, as its baseline character cannot be fully established.

28 Gilmour, S & Church, M (2002) ‘On the edge of the earth? Recent research in Uig, Lewis’, Scottish Archaeological News 38, 20002, 6-7. 29 Carter, S Dalland, M Long, D & Barrie, D (2005) ‘Early land-use and development in Arisaig’, Scottish Archaeological Internet Report (SAIR) Report 15, 2005.


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FIELD SYSTEMS AND OTHER AGRARIAN FEATURES

9.5.48 Several field banks, forming an irregular field system (63), are depicted on the Ordnance Survey 1st and 2nd Edition maps to the north of Hollandmey Farm. Little survives today of this field system; the area has been substantially ploughed for forestry plantation and partially planted with commercial conifer trees. Fragments of field banks (63a-b) associated with the field system do, however, survive in open areas within the forestry. The field banks are much denuded and visible as turf and stone banks spread to 2 m wide and 0.2 m high with what appear to be slight ditches running along their southern sides. Given the poorly preserved and fragmentary nature of the remains of the field system (63) they are considered to be of lesser heritage importance.

9.5.49 A series of rectilinear fields (65) are depicted on the Ordnance Survey 1st Edition map immediately north of Hollandmey Farm (Hollandmey Moss). The fields, enclosed by drystone walls, are still in use today. They form part of the farm land between Hollandmey and Philips Mains and are of lesser heritage importance.

9.5.50 A rectangular enclosure (87) is depicted on the Ordnance Survey 1st Edition map but not depicted on the Ordnance Survey 2nd Edition map. No remains of the enclosure now survive in an area of commercial forestry and it is of lesser heritage importance.

QUARRIES

9.5.51 A quarry site comprising four quarries (64a-d) is shown on the Ordnance Survey 1st and 2nd Edition maps at ‘Hollandmey’. These quarries survive in varying conditions, but generally survive as hollows visible in on the edge of forestry. They probably date to the 18th/19th century and were likely a source of stone used in the construction of buildings and field walls at ’Hollandmey. They are considered to be of lesser heritage importance.

MISCELLANEOUS

9.5.52 The Ordnance Survey 1st Edition map depicts a former water channel (59) just east of the remains of a former corn drying barn (58a). This dried out channel is still visible (3-4 m wide and 1 m deep) within an area of rough grazing. The channel runs parallel with the route of the Link Burn and may have been a former course of the burn; it is considered to be of lesser heritage importance.

9.5.53 An old boundary marker (or milestone) (70) was recorded at the side of a modern farm access track leading to Philips Mains Farm. It is not depicted on the Ordnance Survey 1st or 2nd Edition maps and there are no markings visible on the stone. It is not clear whether the stone stands in its original position, but it could have been placed to mark the boundary between the Hollandmey and Philips Mains Farms. It is considered to be of local heritage importance.

9.5.54 A well (62) is shown on the Ordnance Survey 1st and 2nd Edition maps at Shielton, however, no upstanding remains of this well were visible during the field survey in an area of dense heather and the site is considered to be of lesser heritage importance.

Archaeological Potential (OHL and Underground cable)

9.5.55 The landscape in this area consists principally of rough pasture and moorland although some improved pasture/arable land is present at Lochend.


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9.5.56 The HER records a number of prehistoric sites close to the OHL elements of the Proposed Development. These sites include: • a Neolithic chambered cairn (Earl’s Cairn) (MHG1984) at Inkstack, 1 km west;

• a possible Iron Age Broch site (MHG2251) at Hollandmey, 500 m east; and

• artefact find-spots, a Bronze Age sword (MHG2242) and rapier (or dirk) (MHG2243), uncovered close to Mey in the early 20th century, 1 km to the north.

9.5.57 These remains indicate that the areas around Hollandmey and Inkstack (west of Loch Heilen) have been a focus for settlement and activity from the early prehistoric periods onwards.

9.5.58 Further evidence for potential early settlement in the area is provided by the Ordnance Survey 1st Edition map which depicts unroofed settlements close to the Proposed Development at Greenland (south of Loch Heilen) indicating that these had been abandoned by the mid-19th century. A number of unnamed farmsteads (or townships) are depicted in this area on Roy’s map (1747-5530) suggesting that these settlements were occupied during the 18th century and likely have earlier origins.

9.5.59 In addition, isolated settlement features and agrarian structures (including shieling huts and former field systems, sheepfolds and enclosures) have been recorded within areas of moorland within the LOD of the Proposed Development. Many of these sites probably date to the post-medieval period, or potentially earlier. Taking this into consideration it is judged that there is a moderate potential for further buried archaeology to survive within this section of the LOD of the Proposed Development.

Future Baseline

9.5.60 If the Proposed Development was not to proceed there would likely be no immediate change to the baseline condition of the heritage assets identified unless they were affected by future land use changes unrelated to the Proposed Development.

9.6 Potential Impacts Assumptions

9.6.1 For the purpose of this assessment direct (construction) impacts have been based on the indicative underground cable route, OHL route and tower positions and access track routes. It is considered that there is potential for a direct impact to occur on heritage assets with known or potential physical remains: • within 50 m of the tower locations, to take into account working areas around

towers and vehicle movement at these locations;

• along and within close proximity to the proposed underground cable route;

• along and within close proximity to the proposed access track routes; and

• within the proposed Sealing End compounds and temporary laydown areas.

30 Roy, W 1747-55 Military Survey of Scotland


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9.6.2 The Proposed Development as shown in Figures 9.1a-9.1h is based on the proposed alignment and tower schedule as set out within Chapter 2: Description of the Development). Any changes to the proposed layout of the development could potentially result in changes to the predicted impacts set out below and would require to be further assessed. Information regarding construction methodology is as set out within Chapter 2: Description of Development.

OHL


9.6.3 Any ground breaking/disturbance activities associated with the OHL elements of the Proposed Development have the potential to disturb or destroy features of cultural heritage interest. Other construction activities, such as vehicle movement and storage of construction materials, within the LOD of the Proposed Development also have the potential to cause direct, adverse, permanent and irreversible impacts on the cultural heritage (all potential impacts listed in Technical Appendix 9.1 are such).

9.6.4 The potential direct impacts result principally from possible ground disturbance close to cultural heritage assets associated with the erection of the OHL towers and construction of and upgrading of access tracks.


9.6.5 The construction and presence of the Proposed Development may affect adversely the setting of heritage assets in their vicinity. Such effects would be permanent over the life of the Proposed Development. Effects relating predominantly to the settings of heritage assets can occur during both the temporary construction phase and the operational phase.

9.6.6 Construction activities such as conductor stringing, scaffolding and temporary access tracks have the potential to indirectly affect the setting of sites of heritage assets both within the LOD of the Proposed Development and in the wider landscape. These construction activities however, would be temporary, resulting in only a short-term/low impact effect on heritage assets in close proximity to the Proposed Development and would have no permanent effects. Therefore indirect temporary impacts have not been assessed on a site by site basis.

9.6.7 The effects of the operation of the Proposed Development on heritage assets, is provided on a site by site basis in Technical Appendix 9.4 and the residual effects are discussed in Section 9.8: Appraisal of Residual Impacts.

Underground Cable


9.6.8 Ground breaking/disturbance activities associated with the laying of the underground cable elements of the Proposed Development have the potential to disturb or destroy features of cultural heritage interest. Other construction activities, such as vehicle movement and storage of construction materials within the LOD of the Proposed Development , also have the potential to cause direct, adverse, permanent and irreversible impacts on heritage assets (all potential impacts listed in Technical Appendix 9.2 are such).


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9.6.9 The potential direct impacts result principally from possible ground disturbance close to cultural heritage assets associated with the underground cable sections and construction of and upgrading of access tracks.


9.6.10 The underground cable elements of the Proposed Development, once constructed, would have no above-ground visibility and would have no effect on the setting of cultural heritage assets within the surrounding landscape. As a consequence the underground cable elements of the Proposed Development are not considered when assessing the potential impacts of the Proposed Development on the setting of cultural heritage assets.

9.7 Mitigation Mitigation by Design


9.7.1 The location and definition of the Proposed Development has been informed by various routing principles, which, amongst other things have sought to avoid and reduce impacts on cultural heritage and archaeological assets where ever possible. Chapter 4 describes the route selection and alternatives considered and explains, where environmental considerations have influenced the process. The undergrounding sections of the Proposed Development offer significant design mitigation to potential impacts on setting of cultural heritage and archaeology assets for receptors at the western and eastern ends of the Proposed Development when compared to an OHL through these areas.


9.7.2 The location and definition of the Proposed Development has sought to avoid direct impacts arising on known cultural heritage assets within close proximity to the Proposed Development (as shown on Figures 9.1a and 9.1f-h) wherever possible.

9.7.3 The undergrounding itself between Lochend and Philips Mains provides effective mitigation to the potential visual impacts of the Proposed Development on the setting of Category A Listed Castle of Mey and its associated GDL.


9.7.4 Mitigation measures would be implemented to avoid, reduce or offset the likely direct (physical) impacts of the Proposed Development on heritage assets. This is in line with requirements of national, regional and local planning policies set out in Section 9.2.

9.7.5 Suitable programmes of mitigation would be prepared and presented in a Written Scheme of Investigation (WSI) for the approval of The Highland Council prior to the commencement of any construction works. Provision would be made within the WSI for an appropriate programme of investigation and recording of any archaeological remains identified as a result of any mitigation works undertaken in advance of, or during construction works, that cannot be preserved in situ. All works would be conducted by a professional archaeological organisation (Archaeological Clerk of Works). The mitigation works would include the consequent production of written reports on the findings of the archaeological work


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conducted, with post-excavation analyses, publication and archiving of the results of the work where appropriate.

9.7.6 A CEMD/CEMP would be prepared defining the methodologies and management measures to be employed in the construction of the Proposed Development (Refer to Section 2.11 and Appendix 2.1). The CEMD/CEMP would include, amongst other information, written guidelines which would be issued for use to all construction contractors, outlining the need to avoid causing unnecessary damage to known heritage assets. The guidelines would include arrangements for calling upon retained professional archaeological support in the event that buried archaeological remains of potential archaeological interest (such as building remains, human remains, artefacts etc.) are discovered in areas not subjected to archaeological monitoring. The guidance would make clear the legal responsibilities placed upon those who disturb artefacts or human remains.

9.7.7 The following mitigation strategy is proposed during the forestry felling and construction phases of the Proposed Development.


ADDITIONAL WALKOVER FIELD SURVEY

9.7.8 A walkover field survey would be carried out, along the areas of the LOD of the OHL elements of the Proposed Development at Auchingills, including heritage assets 16-21, which could not be accessed during the initial walkover survey (see Figure 9.1b), to identify and record the locations/extents of any previously unrecorded upstanding remains in this area and to record the extents and current conditions of known sites that lie within the LOD of the Proposed Development.

9.7.9 Walkover field survey would also be carried out within the Associated Works LOD at Tows, Durran (see Figure 9.1c for area location) following clearance of dense gorse bushes and conifer trees in this area, to record the locations/extents of any previously unrecorded upstanding remains in this area.

IMPACT AVOIDANCE – PRESERVATION IN SITU / MARKING-OFF

9.7.10 Construction and ground-breaking works at proposed tower locations and access tracks would seek to avoid known cultural heritage assets (Figure 9.1a-9.1f). Procedures would include the exclusion of heritage assets from working areas, and avoidance of assets when planning access routes for construction areas.

9.7.11 Where assets survive as upstanding features and lie within c. 50 m of proposed tower locations they would be avoided as far as is practicable in order to ensure their preservation in situ. Where appropriate, assets would be marked-off using hi-visibility fencing placed, wherever possible, a minimum of 10 m from the visible extent of the heritage asset, to prevent avoidable accidental damage occurring to the remains during construction activities in their vicinity.

IMPACT REDUCTION – PROTECTION OF FEATURES CROSSED BY ACCESS TRACKS

9.7.12 Where linear assets survive as upstanding features, principally banks and walls, access tracks would be routed through any existing gates or broken (less well preserved) sections where possible.


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IMPACT OFFSET – INVESTIGATION AND RECORDING

9.7.13 Where upstanding features cannot be avoided or protected during the construction these areas would be investigated and recorded prior to any construction works being carried out, to a specification and standard to be agreed in writing with The Highland Council and in consultation with HET. In addition, it is considered that there is a moderate potential within the whole of the LOD for the OHL elements of the Proposed Development including associated works, for the preservation of buried remains of archaeological interest. Any requirements for archaeological monitoring of works/watching briefs would be agreed in consultation with HET.

9.7.14 If significant discoveries are made during archaeological monitoring and preservation in situ of any such heritage assets is not possible, provision would be made for an appropriate amount of investigation and recording to be agreed in writing with The Highland Council through consultation with HET. This provision would include the consequent production of written reports on the findings, with post-excavation analyses and publication of the results of the work where appropriate.

IMPACTS ON SETTING

9.7.15 Commitments to landscape and visual mitigation during construction are set out within Chapter 6: Landscape and Visual Impact Assessment.


IMPACT AVOIDANCE – PRESERVATION IN SITU / MARKING-OFF

9.7.16 Construction and ground-breaking works within the LOD for the underground cable elements of the Proposed Development would seek to avoid known cultural heritage assets (Figure 9.1a and 9.1f-h). Procedures would include the exclusion of heritage assets from working areas, and avoidance of assets when planning access routes for construction areas.

9.7.17 Where assets survive as upstanding features and lie in close proximity to the proposed Underground Cable Route they would be avoided as far as is practicable in order to ensure their preservation in situ. Where appropriate, assets would be marked-off using hi-visibility fencing placed, wherever possible, a minimum of 10 m from the visible extent of the heritage asset, to prevent avoidable accidental damage occurring to the remains during construction activities in their vicinity.

IMPACT REDUCTION – PROTECTION OF FEATURES CROSSED BY UNDERGROUND CABLE ROUTE

9.7.18 Disturbance of upstanding linear assets (principally banks and walls) that are crossed by the underground cable route would be kept to a minimum.

IMPACT OFFSET – INVESTIGATION AND RECORDING

9.7.19 Where upstanding features cannot be avoided or protected during the construction these areas would be investigated and recorded prior to any construction works being carried out, to a specification and standard to be agreed in writing with The Highland Council and in consultation with HET. In addition, it is considered that there is a moderate potential within the LOD for the underground cable elements of the Proposed Development for the preservation of buried remains of archaeological interest.


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9.7.20 There is a higher potential for encountering buried archaeological remains in certain locations along the LOD, in particular where the route passes the recorded locations of the following assets: • A WWII artillery battery (5);

• The site of a possible late Iron Age broch (23);

• Two farmsteads of late 18th or early 19th century date (27, 84-85); and

• A shieling ground (61).

9.7.21 Detailed requirements for any archaeological monitoring of works/watching briefs would be agreed in consultation with HET.

9.7.22 If significant discoveries are made during archaeological monitoring and preservation in situ of any such heritage assets is not possible, provision would be made for an appropriate amount of investigation and recording to be agreed in writing with The Highland Council through consultation with HET. This provision would include the consequent production of written reports on the findings, with post-excavation analyses and publication of the results of the work where appropriate.



9.7.23 No mitigation measures are proposed in relation to the likely operational effects of the OHL elements of the Proposed Development.


9.7.24 There would be no above ground visibility of the underground cable elements of the Proposed Development once constructed; therefore this section of the Proposed Development would have no effect on the setting of the cultural heritage assets within the study area and no mitigation measures are required.


9.8.1 Using the criteria detailed in Table 9.3-9.5 and taking the Development description outlined in Chapter 2: Description of Development, Technical Appendices 9.1 and 9.2 summarise the predicted residual construction effects on heritage assets within the LOD of the Proposed Development.

9.8.2 In total 55 cultural heritage assets have been identified within (or partially within) the LOD of the Proposed Development (either the OHL, Underground cable or partly within both). Out of these 55 cultural heritage assets it is assessed that there is potential for construction works for the Proposed Development to result in effects on 18 heritage assets. The potential for micrositing is considered sufficient to avoid direct construction effects on the remaining assets.

Residual Construction Impacts

OHL

9.8.3 A total of 37 recorded heritage assets lie within the LOD for the OHL elements of the Proposed Development (including associated works) (Figures 9.1a-9.1f, Technical Appendix 9.1). Of these, construction works associated with the Proposed Development may potentially result in direct impacts on 12 of the


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heritage assets (if they cannot be avoided by construction works) (Technical Appendix 9.1) resulting in greater than negligible residual impacts on five of these assets including: • Three minor residual effects on clearance cairns/spreads (36 and 78) and

quarry (43) (not significant in the context of the EIA regulations).

• Two effects of unknown significance on a farmstead (16) and a possible broch site (23). The effects on these assets are of unknown status as there is currently insufficient baseline information; however, it is considered that there is a potential for a moderate residual impact on the farmstead (16) and a major residual impact on the broch site (23) from the construction of the Proposed Development (significant in the context of the EIA regulations).

9.8.4 No residual effects are predicted on the remaining seven sites, ponds (12, 33 and 39), quarries (21 and 75), an area of peat cuttings (45) and field bank (73), as the predicted direct impact on each is considered to be minimal.

Underground Cable

9.8.5 A total of 20 recorded heritage assets lie within the LOD of the underground cable elements of the Proposed Development (Figures 9.1a and 9.1f-9.1h, Technical Appendix 9.2). Of these, construction works may potentially result in direct (construction) impacts on six of the heritage assets as detailed in Technical Appendix 9.2 resulting in greater than negligible residual impacts on three of these assets, including: • Three minor residual effects on clearance spreads (4), corn drying barn (58)

and a possible kiln (60) (not significant in the context of the EIA regulations).

9.8.6 No residual effects are predicted on the remaining three sites, quarry site (64), field system (65) and farmstead (85), as the predicted direct impact on each is considered to be minimal.

9.8.7 Taking into consideration the proposed mitigation strategy set out in Section 9.7 it is assessed that the majority of the cultural heritage assets that lie within the LOD of the Proposed Development and which could potentially be affected by construction works could be avoided through micrositing of elements of the Proposed Development. Where heritage assets are avoided there would be no predicted residual effects from the Proposed Development.

9.8.8 Where cultural heritage assets cannot be avoided during construction, mitigation to offset and reduce the impact has been proposed (Section 9.7, Technical Appendices 9.1 and 9.2); in these cases, where construction work would disturb cultural heritage assets, the significance of the residual effects on the cultural heritage assets would be the same as the significance of the predicted impact, offset by mitigation through preservation by record.


9.8.9 Analysis of the ZTV (Figure 9.2) indicates that there would be theoretical visibility of one or more components of the Proposed Development from 39 Scheduled Monuments; one Category A Listed Buildings, 18 Category B Listed Buildings, 13 Category C Listed Buildings and one Conservation Area. There are no World Heritage Sites, Gardens and Designed Landscapes or Historic Battlefields with predicted visibility of the Proposed Development within the ZTV.


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9.8.10 A list of heritage assets within the ZTV (Figure 9.2) of the Proposed Development and predicted to have theoretical visibility of one or more components of the Proposed Development is provided in Technical Appendix 9.3. Using the criteria detailed in Tables 9.6 – 9.9, Technical Appendix 9.4 details the finding of the assessment of the residual operational effects of the Proposed Development upon the settings of these heritage assets.

9.8.11 Sites identified by Historic Scotland (Table 9.1) to lie within close proximity to the Proposed Development and to have sensitive settings are considered in detail below. To aid the assessment of these sites, visualisations (listed in Table 9.2) have been produced to show the theoretical views of the Proposed Development Line from each asset. Further details of the methodology used for the ZTV and visualisation which support this assessment are included within Chapter 6: LVIA.

9.8.12 Significant residual operational effects of moderate significance have been predicted on the setting of two assets - Earney Hillock, chambered cairn (439) and Stemster Hill, chambered cairn (486). No other cultural heritage asset within the ZTV would likely receive a significant residual operational effect on its setting from the introduction of the Proposed Development. Justification of this assessment is provided below.

Earney Hillock, Chambered Cairn (439) (Figure 9.3)

9.8.13 This scheduled prehistoric burial cairn of probable Neolithic date survives as a grass-covered mound situated in an improved pasture field at the edge of an extensive boggy area (present to the north-east side) and just north of the Bowermadden to Tain public road. The burial cairn is aligned north-west to south-east and there are four associated orthostatic stones (upright slabs) visible, three of which stand around 9 m from the south-east end of the cairn. The cairn is generally well-preserved standing to a maximum height of 1.7 m and c.34 m long. It stands in a prominent position and extensive views are afforded from the cairn to the surrounding farming landscape in all directions and it is visible in views to the north, from the Bowermadden to Tain public road, back-dropped by surrounding farmland/moorland. The setting of the cairn is characterised by the pasture field in which it stands and the farmland out over which views extend. The key aspects of the setting of the asset would appear to be its topographical setting and the wide views gained from the monument. The chambered cairn has a setting that makes a moderate contribution (surviving in a more recent farming landscape) to its understanding and appreciation and this gives it a setting of high sensitivity.

9.8.14 The cairn forms part of a diverse group of burial cairns surviving within the Caithness area, and there is one other potentially contemporary burial cairn in the immediate vicinity, Copper’s Hill long cairn (RCAHMS Database ref no: ND26NW 2), present c. 1.5 km to the north-west of Earney Hillock chambered cairn. Today the cairn at Copper’s Hill is poorly preserved and little visible remains survive, nevertheless, its location is visible in views from Earney Hillock chambered cairn and there may have potentially been intended intervisibility between the two cairns.

9.8.15 In the immediate landscape surrounding the burial cairn there are several wooden pole overhead lines, particularly visible in views to the north-west running to a modern house that has been constructed approximately 0.3 km from the cairn. A large wind farm development is visible on the distant horizon to the south-west, and two TV/radio masts, standing on the Hill of Olrig, are visible in distant views to the north-west in views towards the coast.


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9.8.16 The Proposed Development would be at nearest around 450 m away from the cairn. Towers from the Proposed Development would be visible in the foreground in moorland/farmland to the north, north-east and north-west of the cairn (Figure 9.3). Elements of the towers would be visible behind the cairn in views of the monument from the public road to the south, whilst the Proposed Development would be seen crossing views from the monument to the location of Copper’s Hill long cairn to the north-west. The Proposed Development would be visible in the surrounding landscape, which forms part of the extensive views out from the monument and would have a material effect upon the wider landscape setting of the cairn. The Proposed Development would represent a highly visible new feature in the surroundings of the cairn, in a landscape that contains few other modern features. However, the Proposed Development is permeable and the landscape surroundings and context of the monument would still be appreciable.

9.8.17 Taking the above into consideration it is assessed that the Proposed Development would have a predicted effect of medium magnitude on the setting of Earney Hillock chambered cairn resulting in an adverse impact of moderate significance (significant in the context of the EIA regulations).

Earl’s Cairn, Chambered Cairn (449) (Figure 9.4)

9.8.18 The earthwork remains of this scheduled Orkney-Cromarty burial cairn of Neolithic date stand in an improved pasture field on the edges of Inkstack village. The burial cairn survives as a round, grass-covered, mound that has been greatly damaged by robbing and ploughing. Extensive panoramic views are afforded from the cairn out to the surrounding landscape; views overlook moorland and commercial forestry to the north-east/east and cultivated land in all other directions. Views to the south-west take in Loch Heilen and long views to Dunnet Head and the north coast are visible in views to the west and north. The burial cairn itself is visible on the horizon, whilst travelling along the public road from Inkstack to Hollandmake. The setting of the cairn is characterised by the pasture field in which it stands and the farmland out over which views extend. The key aspects of the setting of the asset would appear to be its topographical setting and the wide views gained from the monument. The chambered cairn has a setting that makes a moderate contribution (surviving in a more recent farming landscape) to its understanding and appreciation and this gives it a setting of high sensitivity.

9.8.19 Views from the cairn look over the village of Barrock and Inkstack and several buildings (residential housing and farm buildings) are visible within 0.5 km of the cairn to the west/south-west at Hollandmake. A small single wind turbine is visible c. 0.3 km to the north of the burial cairn; a wooden trident overhead line runs past the site on the west and south sides (along the public road), around 0.1 km and 0.2 km away respectively, and an additional pole line is visible running beyond Inkstack farm to the north. A large wind farm development is visible on the distant horizon to the south-west, while another wind farm scheme is visible in long distant views to the north-west close to the coast. Two TV/radio masts at Hill of Olrig are visible also in distant views, on the horizon, in views to the west.

9.8.20 Where the Proposed Development passes the cairn, between Lochend and Philip Mains it would consist of an underground cable which would have no above ground components and which would not affect the setting of the burial cairn. At its closest the OHL elements of the Proposed Development would be over 3km away, to the south (at Lochend) and would be seen in distant views crossing farmland to the south-southeast of the monument at Greenland (Figure 9.4) and extending away from the monument. Views to the cairn from the public road would be unaffected.


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Although a new element in the wider surrounding landscape of the cairn the Proposed Development would only be seen as a minor, distant addition to the landscape in which contains other man-made features. The presence of the Proposed Development would form only a minor change to the wide views obtained from this site and would not affect an ability to understand or appreciate the burial cairn.

9.8.21 It is assessed that the impact of the Proposed Development on the setting of Earl’s Cairn chambered cairn would be of no more than low magnitude and of minor significance (not significant in the context of the EIA Regulations).

Stemster Hill, Chambered Cairn (486) (Figure 9.5)

9.8.22 The earthwork remains of this scheduled chambered, long cairn of probable Neolithic date are situated in scrubby pastureland around 1.2 km to the south of Hilliclay and immediately south-west of the ruins of a former farmstead within the Burn of Auchingills valley. The cairn is orientated north to south and stands 1.2 m high. It is partially covered with gorse bushes and there appears to be some later quarrying along its east side. The cairn is not a prominent feature in the landscape today and it is difficult to distinguish from other gorse covered hummocks in the area, being best appreciated at close quarters. Views from the monument are afforded in all directions: long distant views are particularly gained to the east, overlooking Achingills and Marl Moss, and concentrated down the Auchingills Burn valley. Views in other directions take in immediate surrounding moorland, and farmland around Hilliclay; distant views out in these directions are generally limited by rising topography. A commercial forestry plantation is visible c. 0.6 km to the east, around Fryster, and an overhead transmission line is visible to the north running along the Hilliclay to Durran public road, at a slightly higher elevation than the cairn (approximately 0.9 km away).

9.8.23 The cairn forms one of a number of prehistoric burial cairns that are sited on the slopes of Sordale Hill, including Stemster, long cairn (11239), Sinclair’s Sithean long cairn (480), Sordale Hill, Cnoc na Ciste, chambered cairn (442) and Gallow Hill, long cairns and Chambered cairns (483). These cairns are potentially contemporary and may have been sited specifically with deliberate intervisibility between the monuments; today there is intervisibility between Stemster Hill chambered cairn, Stemster long cairn (11239), Sinclair’s Sithean long cairn (480) and Sordale Hill, Cnoc na Ciste, chambered cairn (442). Intervening topography restricts views from the other burial cairns (483) which are located on the western slopes of Sordale Hill and views from which are concentrated to the west overlooking the Thurso River valley. The setting of the cairn is characterised by the scrubby pasture land it stands in and the farmland/moorland out over which views extend, and its visible relationships with other nearby, potentially contemporary, cairns. The cairn has a setting that makes a moderate contribution (surviving in a more recent farming landscape) to its understanding and appreciation and this gives it a setting of high sensitivity.

9.8.24 The Proposed Development would be present at nearest approximately 350 m to the north of the monument, seen crossing moorland and cultivated fields in views to the north and north-west at Achingills, and running along a forest ride at Fryster north-east of the cairn. The Proposed Development would also be seen crossing the landscape beyond the cairn when viewing the monument from other similar features in the landscape (including burial cairns (442, 480 and 11239), although the intervisibility between the cairns would not be directly affected. The Proposed


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Development would be a new visible feature in the surroundings of the cairn, in a landscape that contains few modern features of comparable type.

9.8.25 It is therefore assessed that the Proposed Development would have a predicted effect of medium magnitude on the setting of Stemster Hill, chambered cairn resulting in an adverse impact of moderate significance (significant in the context of the EIA Regulations).

Tulloch of Shalmstry, Broch (594) (Figure 9.6)

9.8.26 The earthwork remains of this scheduled prehistoric broch are located on the edge of an improved pasture field, around 0.3 km to the south-east of Shalmstry Farm and immediately east of the A9 public road. The remains of the broch survive as a grass-covered roughly oval mound c. 20 m in diameter and 1.8 m high. The monument is orientated north to south and a possible entrance is recorded on the east side. The landscape in which the broch is sited is relatively flat and there are extensive wide, long views afforded from the monument out to the surrounding farm land and distant hills in all directions, particularly overlooking the River Thurso valley to the west. The broch is visible whilst travelling along the A9 public road, and glimpses of the monument can be gained whilst travelling west along the Weydale to A9 public road. The setting of the broch is the farmland in which it sits and out over which views extend.

9.8.27 Two existing wood pole OHL pass the broch, on the east side around 0.2 km away, and on the south side, running from Bulliemore and Todholes Farm, c. 0.3 km away. In addition an existing lattice tower OHL passes the broch remains on the west side (on the opposite side of the A9 public road) within 0.6 km.

9.8.28 The Proposed Development would be present around 1.5 km to the east-south-east of the broch remains, the closest indicative tower location lies just east of Weydale Farm South. The majority of the Proposed Development, where it passes the broch, would be underground at this location and would therefore not affect the setting of the broch. Where the Proposed Development would be visible, it would be seen in distant views crossing farmland to the south-east of the monument (at Weydale and Auchingills) and extending away from the monument (Figure 9.6). The Proposed Development would be only a distant minor addition to views in which other built up elements (including Weydale South Farm and Weydale village) are present and would not affect the immediate farmland setting of the asset. It would also be at a greater distance than the closest steel overhead transmission line, present to the west of the broch and within 0.6 km of the monument.

9.8.29 Although a new feature in the surrounding landscape of the broch, the Proposed Development would not detract from an appreciation or understanding of the monument or its surrounding landscape and it is assessed that the Proposed Development would have an impact of low magnitude and of minor significance (not significant in the context of the EIA Regulations) on the setting of the broch.


9.9.1 The identification of likely cumulative impacts focuses upon the residual operational impacts of the Proposed Development (Proposed OHL) on the setting of cultural heritage assets, in combination with the cumulative developments shown on LVIA Chapter Table 6.15 and Figure 6.26: Other developments within 30 km.


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9.9.2 This appraisal has concentrated upon identifying which of those assets that would likely experience a measurable residual effect on their setting resulting from the presence of the Proposed Development (i.e. with minor or moderate residual operational, indirect effects as set out in the final column of Technical Appendix 9.4) and which might experience an effect of greater significance when considered in combination with the cumulative developments. As the cumulative developments do not occupy the same footprint as the Proposed Development no direct cumulative effects are predicted.

9.9.3 Residual indirect effects of moderate significance have been identified from the Proposed Development in relation to Earney Hillock, chambered cairn (439) and Stemster Hill, chambered cairn (486). • For Earney Hillock chambered cairn (439) the proposed Coghill wind farm (3

turbines), located less than 1 km to the north-east of the cairn, would also be visible in views of the Proposed Development from the heritage asset, but it is considered that the scale of the proposed wind farm would be such that the two proposals together would not give rise to an incremental cumulative effect.

• For Stemster Hill chambered cairn (486) it is possible that a combination of the Proposed Development and the proposed Stemster wind farm (4 turbines), located c.1 km east of the cairn, could lead to a major adverse cumulative effect on the setting of the cairn, since they could together be visible from the cairn in an arc from north-west to east.

9.9.4 Residual indirect effects of minor significance have been identified from the Proposed Development in relation to ten heritage assets, as follows: • Four prehistoric burial cairns are located close to Stemster Hill chambered

cairn (discussed above) – Sordale Hill (442), Sinclair’s Sithean (480) and Stemster long cairn (11239). As with Stemster Hill there is the potential for the presence of both the Proposed Development and the proposed Stemster Wind Farm (4 turbines) to be visible in wide views from north-west to east when looking from these monuments. There is the potential that incrementally these two proposals could lead to moderate significance cumulative effects on the setting of the three scheduled burial monuments (significant in terms of the EIA).

• Halcro Manse broch (556) and Cairn of Heathercow long cairn (434) are both located in close proximity to the proposed Seater Farm Bower Wind Farm (4 turbines). The Proposed Development, in combination with this cumulative development, could give rise to moderate significance cumulative effects on the settings of the two assets, but it is the proposed wind farm that would contribute proportionally more of the effect owing to its greater prominence and proximity to the heritage assets (significant in terms of the EIA).

• Earney Hillock chambered cairn (449) is located in close proximity to the proposed Earl’s Cairn Wind Farm (13 turbines). The Proposed Development, in combination with this cumulative development, could give rise to a moderate significance cumulative effect on the settings of the asset, but it is the proposed wind farm that would contribute proportionally more of the effect owing to its greater prominence and proximity to the heritage asset (significant in terms of the EIA.

• Tulloch of Shalmstry broch (594) is located in close proximity to the proposed Buckies Farm wind farm (5 turbines) and the Dounreay to Mybster Overhead Electricity Line (OHL), which runs passed the broch on its west side. There is potential for the presence of both the Proposed Development together with the


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proposed Buckies Farm wind farm and the existing Dounreary to Mybsert OHL to give rise to a moderate significance cumulative effect on the setting of the broch (significant in terms of the EIA), but, it is judged that the cumulative effect from the addition of the Proposed Development (at 1.5 km away) would be minimal.

• No specific potential incremental cumulative effects are considered likely in relation to Ring Hillock cairn (474), Stone Lud cairn (487) and Ring of Castlehill fort (576).


9.10.1 A desk-based assessment and reconnaissance field survey were carried out for the LOD of the Proposed Development (including associated works). The assessment has been informed by comments and information supplied by Historic Scotland.

9.10.2 Thirty-seven cultural heritage assets (sites and features) were identified within the LOD for the OHL elements of the Proposed Development (including associated works). The majority of these features are associated with post-medieval settlement and agrarian activities, although one potentially prehistoric site, the former location of a possible broch (23), was recorded at Hillicay.

9.10.3 The OHL elements of the Proposed Development would cross principally areas of pasture or arable fields that have been ploughed and substantially improved from the 19th century onwards, although there are areas of rough grazing and unmodified moorland (bogland) present towards the eastern end of the OHL LOD at Moss of Greenland. The HER records several prehistoric sites close to the Proposed Development and although many of these features and artefacts no longer survive as in situ remains they indicate that the area has been a focus for settlement and activity from the early prehistoric periods onwards. It is considered that there is a moderate potential for further buried archaeology to survive within this section of the Proposed Development LOD.

9.10.4 The residual impacts predicted to arise from the construction and operation of the OHL elements of the Proposed Development are summarised in Tale 9.11.




Construction

Potential minor and direct impacts are predicted on three heritage assets: heritage assets (36, 43 and 78)

Microsite to avoid asset, where possible; Mark-off during construction works as need; Any areas where disturbance is unavoidable should be recorded archaeologically prior to construction works.

The scope of works would be detailed in a Written Scheme of Investigation (WSI) and approved by The Highland Council.

No residual impact if avoided. Minor residual impact if assets cannot be avoided.


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Potential direct impacts of unknown significance are predicted on two heritage assets: heritage assets (16 and 23) (the effects on these assets are of unknown status as there is currently insufficient baseline information, however it is considered that there is a potential for an impact of moderate significance on heritage asset (16) and an impact of major significance on heritage asset (23))

Assets that are recorded at Achingills and which could not be visited during the initial field survey (Assets 16-22; see Figure 9.1b for area) would be visited to record the current baseline of each asset: Microsite to avoid assets where possible; Mark-off during construction works as needed; Any areas where disturbance is unavoidable should be recorded archaeologically prior to construction works; and Construction phase archaeological watching briefs where the OHL passes assets 23 and 27 where there is higher potential for encountering buried archaeological remains.


Unknown residual impact if assets cannot be avoided.

Operation

Impacts of moderate significance predicted on the setting of Earney Hillock, chambered cairn (439) and Stemster Hill, chambered cairn (486)

N/a N/a Moderate residual operational effects. The decommissioning of the Proposed Development and the removal of the towers would return the landscape setting of the asset to its pre-development position.

Impacts of minor significance (not significant in EIA

N/a N/a Minor residual operational effects.


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context) are predicted on the setting of 10 Scheduled Monuments (434, 442, 449, 474, 480, 487, 556, 576, 594 and 11239)

The decommissioning of the Proposed Development and the removal of the towers would return the landscape setting of these assets to their pre-development position.


9.11.1 A desk-based assessment and reconnaissance field survey were carried out for the LOD of the underground cable elements of the Proposed Development. The assessment was information by comments and information supplied by Historic Scotland.

9.11.2 Twenty cultural heritage assets (sites and features) were identified. The majority of these are associated with post-medieval settlement and agrarian activities.

9.11.3 The Underground Cable elements of the Proposed Development would cross principally flat pasture and arable fields that have been substantially improved from the 19th century onwards, although areas of rough moorland are present around Groffistoft Moss and Hollandmey Moss. The HER records several prehistoric sites close to the Proposed Development and they indicate that the area has been a focus for settlement and activity from the early prehistoric periods onwards and it is judged that there is a moderate potential for further buried archaeology to survive within the underground cable elements of the Proposed Development.

9.11.4 The residual impacts predicted to arise from the construction and operation of the Proposed Underground Cable are summarised in Tale 9.12.


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Table 9.12 Summary of Potential Impacts of the Proposed Development, mitigation and Residual Impacts of the Underground Cable elements



Construction

Potential minor direct impacts are predicted on three heritage assets: heritage assets (4, 58 and 60)

Microsite to avoid asset where possible; Mark-off during construction works as need; Any areas where disturbance is unavoidable should be recorded archaeologically prior to construction works; Construction phase archaeological watching briefs where the underground cable passes assets 5, 61, 64, 84 and 85 where there is higher potential for encountering buried archaeological remains.


No residual impact if avoided. Moderate residual impact if assets cannot be avoided.

Operation

There would be no above ground visibility of the Proposed Underground Cable once constructed; therefore the Proposed Development would not affect the setting of cultural heritage assets within the study area.

N/a N/a N/a


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Geology, Hydrogeology and Hydrology

10 GEOLOGY, HYDROGEOLOGY AND HYDROLOGY

10.1 Introduction

10.1.1 This chapter considers the potential impacts on geology, hydrogeology and hydrology of the construction and operation of the Proposed Development.

10.1.2 The specific objectives of the assessment are to:

characterise the baseline in terms of designated sites; solid and superficial geology; hydrogeology; surface water hydrology; water resources and water quality;

investigate the presence/possible presence of peatland hydrology and groundwater dependent terrestrial ecosystems (GWDTEs) within the study area;

describe the likely potential impacts during construction and the operational phase of the Proposed Development on geology, surface water and groundwater resources, surface and groundwater quality, flooding and any GWDTEs identified;

describe both the design and construction mitigation measures that have been committed to/are required in order to avoid or reduce impacts; and

assess the significance of residual impacts that are likely to remain following implementation of mitigation and restoration measures.

10.1.3 This chapter and the impact assessment described within has been undertaken by Chris Day BSc MSc and Simon Gaskell BSc MSc MCIWEM C.WEM C.Env of Ramboll Environ UK Limited (Ramboll Environ). All field surveys were undertaken by suitably-qualified Ramboll Environ ecologists and hydrologists.


10.2.1 Table 10.1 provides details of the consultation responses received in relation to geology, hydrogeology and hydrology and explains how and where these are addressed in the ES.


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Chapter 10: Geology, Hydrogeology and Hydrology 10-2 LT000022



SEPA The layout and design of the Proposed Development, including any associated borrow pits, hardstanding and roads, should avoid impact on wetlands or peatland systems present.

A Phase 1 habitat survey should be carried out for the whole site and all wetland areas should be identified. A National Vegetation Classification (NVC) survey of wetlands should be completed in order to identify any groundwater dependent terrestrial ecosystems (GWDTEs).

An Extended Phase 1 Habitat Survey and a targeted National Vegetation Classification (NVC) have been undertaken and is reported in Chapter 7: Ecology.

The results of these surveys have been used to inform the design of the Proposed Development as well as the assessment of potential impacts on GWDTE, as described within this chapter.

SEPA The ES should identify if wetlands within the study area are GWDTEs.

The route of roads, tracks of trenches within 100 m of GWDTEs should be reconsidered.

The locations of borrow pits or foundations within 250 m of GWDTEs should be reconsidered.

The routing process as summarised within Chapter 4 of this ES has been informed by the Extended Phase 1 Habitat Surveys and NVC survey and has sought to avoid areas of potential GWDTE where ever possible. The selection of proposed access track routes also aimed to avoid GWDTEs where feasible. Where this was not feasible, it has been proposed that all proposed sections of track within a GWDTE would be constructed using floating road techniques (a trackway or similar) as discussed in section 10.6.6 of this chapter.


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SEPA Where the proposed infrastructure will impact upon peatlands, a detailed map of peat depths (this must be to full depth) should be submitted. The ES should detail the likely volumes of surplus peat that will be generated and the principles of how the surplus peat will be reused or disposed of.

Chapter 4 of this ES summarises the process of iterative design development which has been delivered, including, in order to minimise the requirement for either OHL or underground cable to cross extensive areas of deep peat (>1m depth).

Nonetheless, commitments required to be incorporated into a detailed peat management plan in the areas where disturbance to peatland may occur are set out within section 11.6 of this ES.

A detailed peat management plan, including peat depth survey will be completed following micrositing to confirm localised areas of peat by the principal contractor, prior to construction commencing.

SEPA A list of groundwater abstractions both within and outwith the site boundary, within a radius of i) 100 m from roads, tracks and trenches and ii) 250 m from borrow pits and foundations) should be provided.

If groundwater abstractions are identified within the 100 m radius of roads, tracks and trenches or 250 m radius from borrow pits and foundations, then either the Applicant should ensure that the route or location of engineering operations avoid this buffer area or further information and investigations will be required to show that impacts on abstractions are acceptable.

No active abstractions have been identified within the study area.


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SEPA In order to meet the objectives of the WFD of preventing any deterioration and improving the water environment, developments should be designed to avoid engineering activities in the water environment wherever possible. The water environment includes burns, rivers, lochs, wetlands, groundwater and reservoirs. We require it to be demonstrated that every effort has been made to leave the water environment in its natural state. Engineering activities such as culverts, bridges, watercourse diversions, bank modifications or dams should be avoided unless there is no practicable alternative.

Chapter 4 of this ES summarises the process of iterative design development which has been delivered.

A description of the Proposed Development is set out within Chapter 2: Description of Development.

Mitigation measures to prevent impacts on the water environment are set out in section 10.6 of this chapter.

SEPA Where water abstraction is proposed we request that the ES, or planning submission, details if a public or private source will be used.

No water abstractions are proposed.

SEPA The proposed route should be assessed for flood risk and if the engineering works proposed are likely to result in increased flood risk to people or property then a flood risk assessment should be submitted in support of the planning application and SEPA should be consulted.

Areas at risk of flooding, as identified by SEPA, are set out in section 10.5 of this chapter. The Proposed Development itself is not considered to be vulnerable to flood risks.

Risks associated with the construction phase will be mitigated through design and through measures as described in section 10.6 of this chapter which will be set out in the Construction Environmental Management Document (CEMD).

SEPA A site survey of existing water features and a map of the location of all proposed engineering activities in the water environment should be included in the ES.

Baseline characterisation is set out within section 10.5 of this chapter.

A summary of potential impacts and proposed mitigation is set out in Table 10.6 within this chapter.

SEPA A CEMD is a key management tool to implement the Schedule of Mitigation. SEPA recommend that the principles of a CEMD are set out in the ES outlining how the draft Schedule of Mitigation will be implemented.

A project specific CEMP will be developed by the principal contractor prior to construction commencing.


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SNH The impacts of the temporary construction accesses, and other ancillary works, should be considered in the EIA.

Assessment of residual impacts relating to geology, hydrology and hydrogeology are set out in section 10.7 of this chapter. Mitigation measures are set out within section 10.6 of this chapter.

10.3 Assessment Methodology

Baseline Characterisation

Study Area

10.3.1 The study area for the identification and evaluation of baseline conditions and potential impacts with regard to potential water receptors has been defined as the Limits of Deviation (LOD) of the Proposed Development, plus an additional 2 km distance from this boundary (Shown in Figures 10.1 to 10.3). However, potential hydrology and hydrogeology issues have been assessed at the local river catchment level, where applicable, as impacts on watercourses or groundwater bodies may have an effect which goes beyond the immediate vicinity of the water body.

Desk Study

10.3.2 A desk study was completed using the data sources set out in Table 10.2.

Table 10.2: Baseline Characterisation

Topic Sources of Information

Topography Aerial Photography

1:25,000 Ordnance Survey (OS) Raster Data

Designated Nature Conservation Sites

In-house Designated Site database

SNH Sitelink website (http://www.snh.org.uk/snhi/)

Solid and Superficial Geology British Geological Survey (BGS) Digital Data provided at www.emapsite.com

Borehole Records from the BGS GEOINDEX, www.bgs.ac.uk

Surface Water Hydrology 1:10,000 OS Raster Data

1:25,000 OS Raster Data

FEH CD-ROM

Flooding Indicative River and Coastal Flood Map (SEPA) www.sepa.org.uk

Water Quality SEPA RBMPs from Web Mapping Application: http://gis.sepa.org.uk/rbmp/

SEPA RBMP for the Scotland river basin district 2009 – 2015


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Table 10.2: Baseline Characterisation

Topic Sources of Information

Water Resources Private water supply information provided by The Highland Council



Hydrogeology SEPA, 2004, Vulnerability of the Groundwater in the Uppermost Aquifer, SEPA 2004

SEPA, 2004, Bedrock Aquifer Map

SEPA, 2004, Superficial Aquifer Map

SEPA, River Basin Management Plans, Web Mapping Application, http://gis.sepa.org.uk/rbmp/

Site Survey

10.3.3 An Extended Phase 1 Habitat Survey was carried out between August 2011 and September 2011 following best practice guidance1. (refer to Chapter 7: Ecology) The study area was resurveyed in both 2012 and 2013, in order to verify and update the Phase 1 habitat maps.

10.3.4 A targeted National Vegetation Classification (NVC) survey was undertaken in October 2013, focussing on areas identified as possibly being GWDTEs during the Phase 1 habitat surveys.


10.3.5 Potential geology, hydrogeology and hydrology impacts have been predicted and assessed based on the proposals as described in Chapter 2: Description of Development. The Proposed Development would involve a range of enabling works, construction and the eventual operation of the OHL, including the installation of electrical infrastructure and underground cabling circuits.

10.3.6 Potential effects which may occur as a result of the Proposed Development were identified throughout the initial screening and scoping processes and on the basis of the responses listed in Table 10.1 above from SEPA and SNH. Effects were described as: direct or indirect; permanent or temporary; and beneficial or adverse.


10.3.7 Sensitivity of individual receptors has been defined in terms of high, medium or low sensitivity as defined in Table 10.3 below. Effects on water resources were described as beneficial, neutral or adverse and are considered with reference to the sensitivity of the receptor, as described in Table 10.3.

Table 10.3: Sensitivity of Environmental Resource

High EC Designated Salmonid / Cyprinid fishery.

Surface water WFD class 'High'.

Scottish Government Drinking Water Protected Areas.

1 JNCC (2010) Handbook for Phase 1 habitat survey, JNCC Peterborough


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Table 10.3: Sensitivity of Environmental Resource

Aquifer providing regionally important resource such as abstraction for public water supply, abstraction for private water supply.

Supporting a site protected under EC or UK habitat legislation/species protected by EC legislation.

Protected Bathing Water Area.

Active floodplain.

Highly Groundwater Dependent Terrestrial Ecosystems.

Medium Surface water WFD class 'Good' or 'Moderate'.

Aquifer providing water for agricultural or industrial use.

Local or regional ecological status / locally important fishery.

Contains some flood alleviation features.

Areas of deep peat (greater than 1.5m depth).

Moderately Groundwater Dependent Terrestrial Ecosystems.

Low Surface water WFD class 'Poor'.

Unproductive strata / no abstractions for water supply.

Sporadic fish present.

No flood alleviation features.

Sewer.

Magnitude of Impact

10.3.8 The size or magnitude of each impact was determined as a predicted deviation from the baseline conditions during construction, operation and decommissioning, as described in Table 10.4 below.

Table 10.4: Magnitude of Impact on a Receptor

Magnitude of Impact Criteria

Major Results in loss of attribute. Fundamental (long term or permanent) changes to geology, hydrology, water quality and hydrogeology. (e.g. resulting deterioration and change in reclassification of watercourse status).

Moderate Results in effect on integrity of attribute or loss of part of attribute. Material but non-fundamental and short to medium term changes to the geology, hydrology, water quality and hydrogeology.

Minor Results in minor effect on attribute. Detectable but non-material and transitory changes to the geology, hydrology, water quality and hydrogeology.

Negligible/None Results in an effect on attribute but of insufficient magnitude to affect the use/integrity. No perceptible changes to the geology, hydrology, water quality and hydrogeology.


10.3.9 The significance of residual effects was defined as a function of the sensitivity of receptors and the magnitude of change, as presented in Table 10.5 below, taking account of any mitigation proposed.


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Magnitude of Impact

Negligible/None Minor Moderate Major


High Negligible/None Minor Major Major

Medium Negligible/None Minor Moderate Moderate

Low Negligible/None Negligible Minor Minor

10.3.10 Differentiations between categories, and thus the final significance ratings, were based upon professional judgement.

10.4 Baseline Conditions

Current Baseline

Geology and Hydrogeology

10.4.1 The geology within the study area typically comprises drift deposits of diamiction, boulder clay with isolated pockets of peat. The BGS mapping for the area2 indicates peat in the area of the Moss of Greenland and Hollandmey Moss, towards Gills Bay to the east. Section 11.5 provides further detail Alluvium deposits are recorded in the vicinity of Durran and Borgie Mains. Further alluvium is located around Loch Heilen. These drift deposits are further underlain by bedrock comprising Upper Caithness flagstone group, including Scrabster Flagstone, Achrscrabster Flagstone, and Sandside Bay sandstone. The Upper Caithness flagstone group is generally described as laminated carbonate rich siltstones and shales with subordinate fine-grained, thinly bedded sandstones. The BGS mapping for the area groups the solid geology over the study area into the Middle Old Red Sandstone.

10.4.2 The BGS Hydrogeology and Groundwater Vulnerability Maps (1: 625 000) indicate that the study area is underlain by a moderately permeable aquifer. While the Upper Caithness Flagstone Group will seldom produce large quantities of water for abstraction, and no such abstractions have been identified through this assessment, it is important for local supplies and for supplying base flow to rivers. Within the Caithness area, the bedrock is classified as a locally important aquifer, and groundwater is largely confined to a shallow zone of weathered rock and borehole yields are limited.

10.4.3 The Weydale Quarry Site of Special Scientific Interest (SSSI) is located within the study area. This SSSI is designated due to its geology and is located 950 m north of the LOD of the Proposed Development.

Hydrology

10.4.4 The study area includes a number of burns and smaller watercourses, which are shown on Figure 10.1. Specific engineered watercourse crossings (locations at which access tracks or the underground cable element would directly cross the watercourse) are identified in Figure 10.2. The following burns have been identified, listed from south-west to north-east along the route:

2 BGS Map and Map data viewers (www.bgs.ac.uk/data/mapViewers/home.html)


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Meikle Burn/Burn of Achingills (a tributary of the River Thurso);

Burn of Durran draining into the Burn of Garth;

Burn of Hunster draining into the Burn of Bower;

Burn of Reaster;

Burn of Ham (a tributary of Loch Heilen);

Link Burn;

Burn of Ormigill (a tributary of the Link Burn); and

Burn of Horsegrow.

10.4.5 The LOD of the Proposed Development does not directly cross any lochs. However, the following lochs are in hydraulic connectivity with the Proposed Development:

Loch Heilen, located 0.4 km north west;

Loch Mey, located 2.3 km north-west; and

Loch of Wester, located 8.8 km south-east.

Flood Risk

10.4.6 Parts of the study area are classified as floodplain and SEPA's Indicative River and Coastal Flood Map for Scotland3 indicates that two of the watercourses crossed by the Proposed Development lie within an area shown to comprise a high likelihood of flooding. These are:

the Burn of Durran, at NGR 320450 963400; and

the Link Burn, at NGR 327700, 969700.

10.4.7 SEPA define areas with a ‘High’ likelihood of flooding as being land within which a flood event is likely to occur in the defined area on average once in every ten years (1:10); or a 10 % chance of occurrence in any one year.

Surface Water Quality

10.4.8 The Link Burn and the Burn of Ham were classified in 2008 by SEPA4 under the WFD as having overall ‘Good’ status. The Burn of Garth was classified as having overall ‘Poor’ status and the Burn of Bower was classified as having overall ‘Bad’ status. The other watercourses within the study area are not classified by SEPA. These burns are shown on Figure 10.1.

10.4.9 Loch Heilen was classified as having overall ‘Moderate’ status.

10.4.10 The Duncansby Head to Noss Head coastal waterbody, downstream of the Proposed Development was classified as having overall ‘High’ status. All other downstream coastal waterbodies were classified as having overall ‘High’ status.

10.4.11 Groundwater beneath the Proposed Development is classified as having a ‘Good’ quantitative and groundwater chemistry class.

3 http://map.sepa.org.uk/floodmap/map.htm 4 http://www.sepa.org.uk/water/river_basin_planning.aspx


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Water Use

CONTROLLED ACTIVITIES REGULATIONS (CAR)

10.4.12 There are a number of CAR licences for abstraction within the study area as shown in Figure 10.3 and listed in Technical Appendix 10.1. However, none of these are directly located within the LOD of the Proposed Development.

PRIVATE WATER SUPPLY (PWS)

10.4.13 There are no current private water supplies listed within THC records, within the study area as shown in Figure 10.3. Although THC held a record of a PWS at Seaview on the Castle of Mey Estate (NGR 329156, 973198), approximately 1.2 km north of the LOD of the Proposed Development, the Principal Environmental Health Officer subsequently confirmed that this property (since re-named Captain’s House) no longer has a PWS.

10.4.14 There are no active PWS with hydraulic connectivity to the LOD of the Proposed Development. The closest PWS is at Seater approximately 4.5 km south of the LOD of the Proposed Development (NGR 324900, 960300). This abstracts from a surface watercourse (a tributary of the Burn of Bower) which does not have hydraulic connectivity to the LOD of the Proposed Development.

Sensitive Receptors

10.4.15 There are a number of areas of habitats with potential to represent GWDTEs that the LOD of the Proposed Development cross. These include:

M15 – Scirpus cespitosus – Erica tetralix wet heath, which is classified as being moderately groundwater dependent5 and therefore of Medium sensitivity;

M23 – Juncus effuses/acutiflorus – Galium palustre rush pasture, which is classified as being highly groundwater dependent and therefore of High sensitivity; and

M25 – Molinia caerulea – Potentilla erecta mire, which is classified as being moderately groundwater dependent and therefore of Medium sensitivity.

10.4.16 M17 – Scirpus cespiosus – eriophorum vaginatum and M19 – Calluna vulgaris – Eriophorum vaginatum Blanket Mire was also identified. However, these habitats are not classified under the GWDTE system as they are a rainwater dependent (ombrogenous) community and are, therefore, not considered to be sensitive receptors in terms of geology, hydrology and hydrogeology.

10.4.17 These habitats are described within Chapter 7: Ecology and are shown on Figure 7.4.

10.4.18 Loch Heilen and Loch Mey are both in downstream hydraulic connectivity with the Proposed Development via the Burn of Ham and the Burn of Horsegrow respectively. These lochs form part of the Caithness Lochs Special Protection Area (SPA) and Ramsar site. The Loch of Wester, connected via the Burn of Hunster and Burn of Bower and the Burn of Reaster, is part of the Caithness Lochs SPA and Ramsar site and is also a designated Special Area of Conservation (SAC).

5 SEPA (2012) Land Use Planning System: SEPA Guidance Note 4


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10.4.19 The River Thurso, located 0.5 km south-west of the Proposed Development and connected via the Burn of Achingills, is designated as a SAC.

10.4.20 The Loch of Durran SSSI is located approximately 0.8 km north of the LOD of the Proposed Development and is connected via the Burn of Durran. Whilst this SSSI does not represent an open body of water, it is designated due to its fen, marsh and swamp habitat.

10.4.21 The Dunnet Links SSSI is located 2.1 km northwest of the LOD of the Proposed Development. The SSSI is designated for its nationally important sand dunes and associated links grassland.

10.4.22 Watercourses in connectivity with the designated sites described above are considered to be of High sensitivity as there is potential for them to impact on the water quality of the designated sites. These include:

Meikle Burn/Burn of Achingills (a tributary of the River Thurso);

Burn of Durran;

Burn of Hunster draining into the Burn of Bower;

Burn of Reaster;

Burn of Ham (a tributary of Loch Heilen); and

Burn of Horsegrow.

10.4.23 The Link Burn is classified by SEPA RBMP process as being of ‘Good’ status and is, therefore, considered to be of Medium sensitivity.

10.4.24 The North Caithness Cliffs SPA is considered to be of High Sensitivity. However, whilst it is in downstream hydraulic continuity, this SPA is located in coastal waters over 5 km from the Proposed Development. Given the distance to the SPA and the volume of the receiving coastal waterbody, the volume of contribution from watercourses connected to the Proposed Development relative to the total volume of water within the SPA is considered to be small. Consequently, direct impacts on the SPA in terms of Geology, Hydrogeology and Hydrology have not been considered further. Impacts on watercourses upstream of the SPA remain a consideration due to the sensitivity of the watercourses themselves or of designated sites in hydraulic connectivity such as the Caithness Lochs SPA as discussed above. The Caithness and Sutherland Peatlands SPA, SAC and Ramsar site is also considered to be if High Sensitivity. However, it is located 3.2 km south-east of the LOD of the Proposed Development and is not considered to be in hydraulic connectivity with the Proposed Development which would be expected to drain in a north-westerly direction at this location following the route of the Burn of Rattar.

10.4.25 Impacts on the Caithness and Sutherland Peatlands SPA, SAC and Ramsar site in terms of Geology, Hydrogeology and Hydrology have not been considered further.

Future Baseline

10.4.26 There is potential for climate change to impact on future baseline conditions. Climate change studies6 predict a decrease in summer precipitation and an

6 Climate Change 2014 Synthesis Report Summary for Policymakers, Intergovernmental Panel on Climate Change


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increase in winter precipitation alongside slightly higher annual average temperatures. This suggests that there may be greater pressures on private water supplies in summer months in the future. Summer storms are predicted to be of greater intensity, therefore, peak fluvial flows associated with extreme storm events may also increase in volume and velocity.


10.5.1 This section briefly describes potential significant impacts which might occur as a result of the Proposed Development, including the direct, indirect, secondary, cumulative, short term, medium and long term, permanent and temporary, beneficial and adverse effects.

OHL


POTENTIAL IMPACTS ON GEOLOGY

10.5.2 No sites designated for their geological interest would be impacted by the Proposed Development. The Weydale Quarry SSSI lies within the study area and is the closest site designated for geological interest. However, it is located 0.8 km north from and up gradient of the LOD of the Proposed Development. No direct works are proposed at the Quarry and no waterbodies are considered to be in downstream hydraulic connectivity with the SSSI which is, therefore, unlikely to be affected by proposed works.

10.5.3 No significant impact on geology is anticipated.

POTENTIAL IMPACT OF ENGINEERING WORKS IN THE WATER ENVIRONMENT

10.5.4 The Proposed Development crosses a number of watercourses and other sensitive receptors including identified incidences of potential GWDTEs (as discussed in section 10.5). Construction activities have the potential for direct physical impacts on sensitive receptors in the water environment, in the event of construction activities, tower placement and access tracks occurring directly within these features or on the banks of watercourses. Specifically, engineering works can cause damage to habitat associated with rivers, lochs and wetlands, in turn affecting populations of invertebrates, plants, birds and mammals, pollution Impact from Silt-laden Runoff.

10.5.5 Surface runoff containing silt, particularly during and after rainfall events, has the potential to enter watercourses in the vicinity of works. Silt-laden surface water runoff may arise from excavations for tower foundations, exposed ground and any temporary material stockpiles. This may temporarily impact on water quality and hydrological and ecological function of receiving watercourses at and downstream of the works.

POLLUTION IMPACT FROM CHEMICAL CONTAMINATED RUNOFF

10.5.6 Pollutants, such as fuel and other contaminants used during construction, may be mobilised through mechanical leaks or spillages and carried in surface drainage. Unless managed appropriately, the pollutants could be washed into watercourses, impacting on freshwater quality and ecological value.


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IMPACT ON INTEGRITY OF BANKING

10.5.7 Vertical vehicular pressure on, or close to the sides of, watercourses can affect the structural integrity of the banks, either through direct damage to bankside material or indirect loosening of soil structure. Such impacts may result in a localised effect on watercourse morphology and water quality through erosion or collapse of the banks.

10.5.8 The Proposed Development crosses several burns, as well as smaller unnamed watercourses and drainage ditches. In addition, features such as small seasonal watercourses may also be encountered during construction.

DIRECT DISCHARGE OF UNTREATED FOUL DRAINAGE

10.5.9 Temporary welfare facilities will be required during construction activities. Unless appropriately located and managed, there is potential for direct discharge of untreated foul sewage to watercourses or water bodies.

DISRUPTION TO ARTIFICIAL LAND DRAINAGE

10.5.10 Construction of the OHL infrastructure may have the following effects on existing land drainage:

drains may be severed by excavation and construction of foundations for the tower legs;

drains may be crushed and destroyed by construction traffic working along the access tracks and at tower locations;

culverts over watercourses and field ditches may not have adequate strength, support or working width to take the weight of the construction machinery; and

Scaffold anchor points at infrastructure and river crossings can puncture or destroy land drains.

DEWATERING OF FOUNDATION EXCAVATIONS

10.5.11 Where low strength ground conditions are encountered due to high water content (peat, alluvium and other low strength materials), foundation excavations may require dewatering. Surface waters generated in this manner would need to be controlled and treated prior to discharge and could have a potential impact on groundwater and surface water conditions, both in terms of flow disruption and mobilisation of sediments.

FLOOD RISK

10.5.12 As detailed in section 10.5 parts of the study area are classified as floodplain. However, since no works associated with OHL construction are proposed on the banks of watercourses, there is not anticipated to be any impact on flood risk down or upstream of the OHL elements of the Proposed Development. The Proposed Development, once operational, is not considered to be sensitive to flooding.


10.5.13 It is considered that there would be no potential for significant impacts from the Proposed Development on geology, hydrogeology and hydrology during the operational phase.


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10.5.14 Permanent works are only proposed on the banks of watercourses at a small number of engineered water crossings. These crossings would be designed and constructed appropriately, such that there is no change in flow conveyance; therefore, it is not anticipated that there would be any impact on flood risk downstream or upstream of the Proposed Development.

Underground Cable


POTENTIAL IMPACTS OF ENGINEERING WORKS IN THE WATER ENVIRONMENT

10.5.15 The underground cable elements of the Proposed Development cross un-named tributaries of the River Thurso in the west and the Burn of Ham, Link Burn, Burn of Ormigill and Burn of Horsegrow in the east as well as routing around the edge of areas of habitat identified as potential GWDTE at Moss of Greenland and Hollandsmey Moss (as shown on Figure 7.4).

10.5.16 An estimated 11% of the total underground cable element of the Proposed Development (1.1km in total) is identified as potentially crossing areas of peat at >1m in depth. This 1.1km total extent is not contiguous, rather is anticipated in broken patches along the underground element of the Proposed Development, and predominately lies on the edge of the larger peat body (Moss of Greenland; Hollandsmey Moss) with which they are associated (as shown on Figure 7.4).

10.5.17 Construction activities have the potential for direct physical impacts on sensitive receptors in the water environment, in the event of the underground cable being directly within or crossing these features.

10.5.18 In terms of areas of GWDTE, the underground cabling works could result in interception and redirection of shallow groundwater flows. This could affect groundwater levels and flows, thereby impacting on the GWDTE.

POLLUTION IMPACTS

10.5.19 Potential pathways for watercourse contamination as a result of the these underground cabling elements are largely similar to those identified for the OHL construction (as discussed above) and include:

runoff of sediment (including waste from forestry works or soils/ peats) from works into watercourses;

direct pollution of watercourses during engineering works in the water environment; and

spillage or leakage of fuels, oils and lubricants from machinery, plant or materials used in construction operations.


10.5.20 Vertical vehicular pressure on, or close to the sides of, watercourses can affect the structural integrity of the banks, either through direct damage to bankside material or indirect loosening of soil structure. Such impacts may result in a localised effect on watercourse morphology and water quality through erosion or collapse of the banks.


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10.5.21 The Proposed Development crosses several burns, as well as smaller unnamed watercourses and drainage ditches. In addition, features such as small seasonal watercourses may also be encountered during construction.


10.5.22 Construction of the underground cable element may have the following effects on existing land drainage:

drains may be severed by excavations;

drains may be crushed and destroyed by construction traffic working along the access tracks;

culverts over watercourses and field ditches may not have adequate strength, support or working width to take the weight of the construction machinery; and

Scaffold anchor points at infrastructure and river crossings can puncture or destroy land drains.

DEWATERING OF TRENCH EXCAVATIONS

10.5.23 Surface waters generated as a result of any required dewatering of the trench would need to be controlled and treated prior to discharge and could have a potential impact on groundwater and surface water conditions, both in terms of flow disruption and mobilisation of sediments.


10.5.24 There are no planned maintenance activities that would impact on geology, hydrology or hydrogeology, as the underground cable would be buried and the landform restored to that formerly present. The Proposed Development would not give rise to any changes in existing ground levels and would not result in any new structures within the floodplain. Any engineered watercourse crossings would be re-instated as part of proposed construction works such that there would be no alteration to the hydrological regime post-construction. There are, therefore, not considered to be any significant issues relating to hydrology from the proposed underground cable once operational.

10.6 Mitigation



10.6.1 As set out in Chapter 4: Route Selection and Alternatives, the location of the Proposed Development was determined through an appraisal of a number of alternate corridor options, followed by consideration of a number of alternative route options through the preferred corridor. Design development was informed by the Holford Rules which set out guidance relating to environmental features that may be considered to be of high amenity. Factors such as surface waterbodies and associated areas of flood risk were considered in this process.

10.6.2 Detailed access proposals will be developed by the Principal Contractor, prior to construction commencing. An initial access track design as set out within Chapter 2: Description of the Development was informed where appropriate, by the Extended Phase 1 Habitat surveys and the targeted NVC survey which focussed on areas identified as possibly being GWDTEs. The selection of proposed access track routes aimed to avoid GWDTEs where feasible. Where this was not feasible,


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initial access track designs proposed that new sections of track within a GWDTE would be constructed using floating road techniques or construction of a temporary trackway. Further consideration of access track construction in areas of GWDTE is set out within section 7.7 of this ES.

10.6.3 The location and layout of welfare facilities etc. will also be the responsibility of the Principal Contractor and would be confirmed within the CEMP as based on the principles set out in the CEMD prior to construction commencing. In order to avoid the potential for direct discharges of untreated foul sewage from temporary welfare facilities to watercourses or water bodies, welfare facilities would either drain to a portable septic tank or connect directly to the foul sewer such that there would be no significant impact.


10.6.4 The alignment of the underground cable element of the Proposed Development has been informed by various routing principles, which, amongst other things, have sought to avoid and reduce impacts on features of geological, hydrogeological or hydrological importance such as surface water features and areas of GWDTE identified during the ecological surveys.




10.6.5 Prior to construction, the approach to the detailed access strategy design and track construction in and around identified GWDTE would have due regard to key principles set out in the joint SNH/FCE guide to floating roads on peat7, including: further use of temporary tracks if necessary; use of the minimum length of track possible within these sensitive habitats; and adherence to best practice in track construction8.

10.6.6 It has been assumed that floating road construction will comprise a layer of geotextile overlaid by approximately 50 cm of crushed concrete/hardcore. It is anticipated that the majority of access will be achieved through upgrade of existing and installation of temporary new tracks.

10.6.7 In the event that any floating roads are proposed to be a permanent installation across areas of GWDTE/peatland, pipes and channels will also be installed beneath the road as a part of the preconstruction Drainage Management Plan (DMP).

10.6.8 The following location specific measures would be followed:

where the new stone road at Achingills crosses areas of high groundwater dependence (in sections of 135 m and 38 m ) construction will incorporate sub-track drainage to allow continued movement of groundwater within these habitats;

sections of temporary road south of Fryster that cross areas of high groundwater dependence (sections of 265m, 110m and 170m) will incorporate

7 FCE, SNH, (2010), Floating Roads on Peat 8 SNH (2013): Constructed Tracks in the Scottish Uplands. 2nd Edition.


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sub-track drainage to allow continued movement of groundwater within these habitats;

sections of temporary road north of Bowermadden that cross areas of high groundwater dependence (sections of 770m and 420m) will incorporate sub-track drainage to allow continued movement of groundwater within these habitats;

a 38m long stretch of floating road will be constructed to the south of Moss of Greenland which will incorporate sub-track drainage to ensure the hydrological connectivity of the habitat remains intact;

the section of temporary road north-west of Reaster that crosses the area of moderate groundwater dependence (a section of 490m) will incorporate sub-track drainage to allow continued movement of groundwater within these habitats; and

where the new stone road north of Reaster crosses areas of high and moderate groundwater dependence (a 635m section) sub-track drainage will be incorporated to allow continued movement of groundwater within these habitats.

PRODUCTION OF CONSTRUCTION ENVIRONMENTAL MANAGEMENT DOCUMENT AND SITE SPECIFIC

DRAINAGE MANAGEMENT PLANS

10.6.9 A CEMD would be prepared defining the policies, procedures and controls to be employed in the construction of the Proposed Development.

10.6.10 The site specific CEMP thereafter prepared by the Principal Contractor would include:

a pollution risk assessment of the site and the proposed activities;

identification of all water bodies that may be affected by the works and temporary discharge points to these watercourses;

planning and design of appropriate pollution control measures during earthworks and construction;

management of the pollution control system, including dewatering of excavations away from watercourses, deployment of pollution spill kits, silt entrapment measures and designated fuelling sites at safe distances away from watercourses;

contingency planning and emergency procedures; and

ongoing monitoring of construction procedures to ensure management of risk is maintained.

10.6.11 Further information on the location of known Scottish Water assets and known PWS at the time of construction would be sought prior to works beginning on-site.

10.6.12 The CEMD would provide for all watercourses within the LOD of the Proposed Development to have 20 m standoff distances established during the construction phase, in which activities would be avoided unless absolutely necessary (such as at watercourse crossings). Pollution spill kits and silt entrapment measures would be provided at all work sites within 75 m of water courses and all personnel would be trained in their deployment. Other measures employed would include bunding of all construction liquids such as fuel or hydraulic fluids and creation of interceptor


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drains around tower construction locations to remove potential pathways to the downstream water environment.

10.6.13 All identified assets would be marked out on the ground before any excavation work can start in the area.

10.6.14 The Principal Contractor would also prepare a DMP prior to construction works as part of the CEMP. The DMP would be a 'living document' which would evolve and be updated throughout the construction life of the Proposed Development.

10.6.15 In accordance with the CEMP, the Contractor(s) would provide a Drainage Mitigation Register, which would include drawings of intended and installed drainage measures and information regarding on-going maintenance. This may comprise a number of separate drainage plans (e.g. drawings, specifications and method statements) for each of the main phases of works, works areas, and works in proximity to sensitive receptors. The purpose of this register and associated plans would be to identify potential risk areas and design bespoke drainage and mitigation measures specific to that particular locality or works activity.

10.6.16 Each individual drainage feature and mitigation measure should be constructed and functional prior to construction of the infrastructure of the Proposed Development which they are intended to service. If this is not feasible then the drainage features should be constructed at the same time as the proposed infrastructure or temporary measures should be installed.

POLLUTION IMPACT FROM SILT-LADEN RUNOFF

10.6.17 Pollution Control measures would be implemented with specific reference to the SEPA 'Guidelines for Water Pollution Prevention from Civil Engineering Contracts' and 'Special Requirements', and incorporated within the CEMD. At all watercourses within the LOD of the Proposed Development, appropriate pollution spill kits and silt entrapment measures would be provided. The CEMD/CEMP would specify measures to manage silt and fines from work sites.

10.6.18 All earth moving works or similar operations would be carried out in accordance with BSI Code of Practice for Earth Works BS6031:1981. While it is acknowledged that best practice to minimise run-off would be to undertake construction during the driest period of the year, given the location of the Proposed Development, there are likely to be significant periods of rainfall throughout the year. Where possible, all temporary stockpiles associated with excavations for individual towers would be located a minimum of 75 m from the edge of watercourses. Where this isn’t possible, pollution spill kits and silt entrapment measures would be provided and all personnel would be trained in their deployment. All construction liquids such as fuel or hydraulic fluids at such stockpiles would be bunded and interceptor drains would be considered around the stockpiles to remove potential pathways to the downstream water environment. All excavations would be backfilled as soon as practicable.

10.6.19 At all construction works areas, greenfield run-off (i.e. non-silty surface water flow that has not yet passed over any disturbed construction areas) would be kept separate from potentially contaminated water from construction areas as much as possible. Where appropriate, interceptor ditches and other drainage diversion measures would be installed, immediately in advance of any excavation works, in order to collect and divert greenfield run-off away from construction disturbed areas.


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10.6.20 Ditches would follow the slope of the ground with a generally constant depth to ditch invert. They should have shallow longitudinal gradients and their purpose is to intercept stormwater runoff and to allow clean water flows to be transferred independently through the works without mixing with construction drainage. Interception and diversion of clean runoff would also prevent significant disruption to shallow groundwater flow, flush areas and blanket bogs reducing the flow of water onto exposed areas of rock and soil, thereby reducing the potential volume of silt-laden run-off requiring treatment.

10.6.21 Greenfield run-off would be discharged into an area of vegetation for dispersion or infiltration. Silt traps, sand bags, silt fencing, anchored straw bales or discharge through a filter medium of selected granular fill may also be installed at the discharge point.

10.6.22 Discharge points (for clean run-off water) would be located at sufficient distance (minimum of 50 m) from any watercourses to allow adequate infiltration or settlement of suspended solids prior to any discharged surface run-off potentially entering the watercourse.


10.6.23 All fuel and other potential chemical contaminants would be stored in accordance with best practice procedures, including a designated fuelling site located at a safe distance from existing watercourses in appropriate impermeable bunded containers/areas which would be defined within the CEMD/CEMP. These would be designed to capture any leakage, whether from a tank or from associated equipment such as filling and off-take points and sighting gauges which would be located within the bund. No mobile storage of fuels or refuelling activities would occur within 75 m of any drain, ditch or watercourse. No permanent or fixed storage of fuel would occur within 100 m of any drain, ditch or watercourse.

10.6.24 Oil booms and soakage pads would be maintained in the site compounds and spill kits would be kept in all vehicles to enable a rapid and effective response to any accidental spillage or discharge. Construction staff would be trained in the effective use of this equipment.

10.6.25 Construction vehicles and plant would be regularly maintained and all maintenance, fuelling and vehicle washing would be undertaken on appropriate impermeable surfaces away from watercourses in order to minimise risks of leaks to soil and surface waters.

10.6.26 The CEMP would provide emergency response contacts, reporting procedures and procedures for dealing with all potential pollution incidents during the construction of the Proposed Development. This would include detailed procedures to be taken in the event of an incident or emergency (including procedures for positioning and movement of plant, use of spill kits, communication etc.).

10.6.27 The DMP would identify drainage flow paths and potential pollution sources. Such sources include car parks, delivery and fuel/chemical storage areas, oil separator equipment, excavations, and any other high risk areas that could give rise to pollution (oil/chemical storage areas, refuelling areas, concrete batching and wash out areas etc.).

10.6.28 The location of potential sensitive environmental receptors would also be set out in the CEMP and associated DMP. All watercourses and drains, including ephemeral


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or seasonal water features within the LOD of the Proposed Development, would be included to ensure issues associated with smaller water features, hydraulically linked with downstream sensitive receptors such as the River Thurso or Caithness Lochs, are addressed.

10.6.29 The location of spill kits and other pollution control or emergency response equipment would also be included in the DMP. This would enable any potential pollution incident during the construction of the Proposed Development to be managed appropriately.


10.6.30 Subject to micro-siting considerations for individual tower locations within the LOD, access tracks, construction vehicles and construction working areas would maintain a minimum stand-off distance of 10 m from the edge of watercourses where possible. In the event that construction activity is required within these limits, such as at proposed engineered watercourse crossings, detailed method statements and risk assessments would be developed by the Principal Contractor(s) and set out in the CEMP and DMP.

10.6.31 Some smaller ditches may need to be passed over by vehicles as part of construction without the formation of engineered watercourse crossings. Should vehicles need to pass over such ditches on sloping ground, tracked machines would be used. If passing of level water features is required, bog mats would be placed across the feature to avoid any damage being caused to the bank or bed. Should any drainage ditches become damaged or blocked as a result of construction vehicles passing over them, these would be repaired or cleared by construction staff immediately. Repair works would refer to the baseline conditions of the affected water body as described in the DMP.


10.6.32 Welfare facilities would either drain to a portable septic tank or connect directly to the foul sewer, and this would be a requirement of the CEMP. If portable septic tanks are to be used, these would be maintained and removed from the Site on a regular basis by a suitably-licensed supplier.


10.6.33 All available information about existing land drainage would be gathered from the Grantors and from a site inspection. The DMP would include the preparation of a plan of known existing land drainage and proposals for site drainage during the works (to inform the design and positioning of mitigation measures).

10.6.34 In some places, pre-construction drainage works would be required. For example, main drains may need to be diverted from a foundation location or to protect a shallow stone sough under an access track. However, this would only be required if it proves not feasible to avoid such features through micro-siting procedures.

10.6.35 It may also be necessary to install pre-working interceptors in areas where the detailed access strategy may require numerous shallow drains that must be crossed. However, in most instances, the full degree of any potential damage to existing drainage schemes would not be known until the foundations are dug. The DMP would be updated with records of any drains encountered during construction where appropriate. Drains severed by the construction process would be


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temporarily reinstated. At post-construction stage permanent diversions would be required. These would not avoid foundation areas.

10.6.36 Where watercourses and ditches are to be crossed, new or upgraded culverts would be required to take the construction traffic. These would be carefully designed to accommodate the design axle loads of traffic. Culvert design would be discussed and agreed with SEPA and constructed in accordance with SEPA guidance9.

10.6.37 Small depressions which remain in the subsoil can exacerbate waterlogging and thereby impact on downstream hydrological and hydrogeological regimes. Any areas vulnerable to such topographic change can be identified during the pre-construction stage. Likewise, drainage problems can also occur around stripped areas (either the towers or the access tracks). Any settlement or soil depression as a result of foundation works or tower placements would be topped up as part of reinstatement works.

10.6.38 Consideration would be given to natural drainage paths within a catchment during development of the DMP prior to construction commencing to ensure they are not altered by the construction. In particular, access tracks can act as small dams diverting water from one catchment to another and potentially causing flood or pollution risk on a wider land area beyond the agreed easement. This would be assessed at pre-construction stage.


10.6.39 Where towers would be located within peat, alluvium or other low strength materials, the CEMP would define measures for the management, removal and disposal of any water ingress into excavations to preserve the integrity and water content of the surrounding ground and to minimise the need for water disposal.

10.6.40 Potential impacts on peat, are described and assessed in Chapter 11: Soils, Land Use and Agriculture. The CEMP will include specific proposals regarding peat, including where deemed necessary as set out within the CEMD, a peat management plan. Further information on mitigation measures for potential impacts on peat are set out within Chapter 11.

FLOOD RISK

10.6.41 Construction within floodplains would be mitigated by ensuring all works in these areas are undertaken during the driest (summer) months to minimize the impact of potential storms. Excavations would be dug and left open for the minimum of time, then immediately back-filled once construction is complete.

10.6.42 The Proposed Development itself is not considered to be vulnerable to interaction with groundwater. Construction works are also not expected to cause significant alterations to the groundwater regime and mitigation measures, to be set out in a CEMP would ensure there is no increase in associated flood risks.

10.6.43 During extreme weather conditions, Contractors would move all heavy plant out of the identified risk areas, in particular adjacent to the Burn of Garth and the tributary

9 SEPA, Engineering in the water environment: good practice guide, River crossings, Second edition, November 2010


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of the Burn of Rattar. The CEMP would include maps showing flood zone areas and instructions on where to move plant to.

10.6.44 The probability of an extreme flood occurring at the same time as construction works are taking place adjacent to a major burn whereby people, machinery and materials would be at risk is considered to be very low. Construction works would not take place during extreme flood conditions or in floodplain areas that are inundated.

MONITORING OF MITIGATION

10.6.45 Mitigation measures would be monitored by an Environmental Clerk of Works (ECoW) throughout construction.


10.6.46 Methods contained within the CEMD/CEMP, as described in Sections 10.6.5 to 10.6.44, would be followed to ensure construction methodologies would not result in damage to the water environment. As detailed above these would specifically include commitments set out above relating to:

content of the CEMD/CEMP;

pollution from silt laden runoff;

pollution impact from chemically contaminated runoff;

impact on integrity of banking;

direct discharge of untreated fowl sewage discharges;

disruption to artificial drainage;

dewatering of cable trench works (same as tower foundations); and

flood risk.

10.6.47 The underground cable element of the Proposed Development crosses surface watercourses on approximately 22 occasions (subject to micro-siting) at un-named tributaries of the River Thurso in the west and within the catchments of the Burn of Ham, Link Burn, Burn of Ormigill and Burn of Horsegrow in the east.

10.6.48 In such instances where engineering works within the water environment would be required, there would be a requirement for a CAR Licence to be issued by SEPA prior to works commencing. The CAR Regulations state that SEPA would not normally require an authorisation under the CAR Regulations for engineering activities at inland wetlands where the wetland is not directly associated with a river, loch or artificial water body. On this basis, it is considered likely that a CAR authorisation would only be required where either a track or the underground cable element crosses a watercourse. Detailed mitigation parameters for inclusion within CAR Licence application will be developed by the Principal Contractor, in line with the commitments within the CEMP.

10.6.49 Detailed mitigation within the CEMP and CAR application would ensure the following requirements:

trenching would be to an estimated depth of 1.4 m or at least 0.9 m below the true clean bottom of watercourses or ditches being crossed;


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flows in watercourses and ditches would be maintained such that there is no change to hydrology either up or downstream of any works, i.e. no significant flow restriction or increase in conveyance;

ensuring there is no pollution of watercourses or ditches during works from sediment during excavation, or chemicals - for example, scour protection and silt management measures would be installed at the discharge of any temporary diversion;

ensuring any diversions of watercourses are subject to restoration across the full working width of the watercourses; and

minimising flood risk by designing flow diversions with sufficient capacity to avoid flood risks.

10.6.50 Given the localised nature of the soil excavations required for cable undergrounding, it is considered that the appropriate approach to soil management will be to strip soils with different characteristics separately as far as possible. The majority of the excavated soil will be replaced on completion of construction of the underground cable. The separation of soil strip material will enable the soils to be restored as closely as possible to their condition pre-construction with minimal change to the hydrogeological regime .Minimal surplus excavated soil is anticipated. Specific measures will be set out within the CEMP for the management of soils.

10.6.51 Works would not commence in advance of proposed methodologies, (and any associated required mitigation), being agreed with SEPA and THC. It is reasonably assumed that a CAR Licence would not be granted were significant effects are identified from the proposed method of working.


10.6.52 There are no relevant mitigation measures required during the operation phase of the Proposed Development.



OHL

POTENTIAL IMPACTS ON GEOLOGY

10.7.1 No sites designated for their geological interest would be impacted by the Proposed Development. No significant residual impact on geology is expected.


10.7.2 The Proposed Development crosses a number of watercourses and other sensitive receptors including identified incidences of potential GWDTEs. Following the implementation of mitigation measures, in particular the avoidance of watercourses and management measures set out in the CEMP, the magnitude of any impact on local surface watercourses is considered to be Minor. The sensitivity of some watercourses is High; therefore the overall impact is predicted to be Minor and not significant.

10.7.3 GWDTEs are habitats which depend on a variety of conditions, including the local hydrological regime maintaining water levels in order to survive. Instances of


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GWDTE identified within the Proposed Development are of either Moderate or High sensitivity and of regional ecological value (see chapter 7 for further detail). The mitigation proposed through design of the OHL elements of the Proposed Development, both in selecting the route of the Proposed Development and the use of floating road techniques to provide access to tower construction locations through these areas, would ensure that hydrological connectivity would not be compromised. Following the implementation of additional mitigation measures described above at each tower foundation site, the magnitude of any impact on GWDTEs with regard to the hydrological regime is considered to be Minor. Therefore the overall residual impact on the hydrological regime affecting GWDTEs is predicted to be Minor and not significant.

10.7.4 The residual impacts in terms of the potential loss or degradation of a small percentage of the total area of GWDTEs are considered unlikely to be ecologically significant (see chapter 7: ecology).

POLLUTION IMPACT FROM SILT-LADEN RUNOFF

10.7.5 Surface runoff containing silt has the potential to enter watercourses in the vicinity of works thereby temporarily impacting on water quality and the hydrological and ecological function of receiving watercourses. Following the implementation of mitigation measures described above, the magnitude of any impact on all watercourses is considered to be Minor. For both watercourses identified as having a High sensitivity and those identified as having a Moderate sensitivity, as discussed in Section 10.5, the overall residual impact is expected to be Minor and not significant.


10.7.6 Pollutants such as fuel and other contaminants used during construction could be washed into watercourses, impacting on freshwater quality and ecological value. Following the implementation of mitigation measures described above, the magnitude of any impact on all watercourses is considered to be Minor. For both watercourses identified as having a High sensitivity and those identified as having a Moderate sensitivity, as discussed in Section 10.5, the overall residual impact as a result of pollution from chemical contaminated runoff is expected to be Minor and not significant.


10.7.7 The Proposed Development would have the potential to detrimentally affect the structural integrity of watercourse banks, in particular at watercourse crossings. Following the implementation of mitigation measures described above, the magnitude of any impact on all watercourses is considered to be Minor. The sensitivity of watercourse banks is identified as Medium-High; therefore, the overall residual impact is expected to be Minor and not significant.


10.7.8 There is potential for direct discharges of untreated foul sewage from temporary welfare facilities to watercourses or water bodies. However, welfare facilities would either drain to a portable septic tank or connect directly to the foul sewer such that no residual impact on water bodies is predicted.


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10.7.9 Localised damage to existing land drainage could occur as a result of the installation of temporary or permanent access tracks and other construction infrastructure. Land drainage is considered to be of local importance and therefore Low sensitivity. Following the implementation of mitigation measures, the magnitude of any impact on local land drainage is considered to be Negligible. Therefore the overall residual impact on land drainage is predicted to be Negligible and not significant.


10.7.10 Surface waters generated as a result of dewatering of foundations could have a potential impact on groundwater and surface water conditions; both in terms of flow disruption and mobilisation of sediments.

10.7.11 Following the implementation of mitigation measures described, the magnitude of any impact on all watercourses is considered to be Negligible. For both water courses identified as having a High sensitivity and those identified as having a Moderate sensitivity, as discussed in Section 10.5, the overall residual impact as a result of pollution from silt laden runoff is expected to be Minor and not significant.

FLOOD RISK

10.7.12 The probability of an extreme flood occurring at the same time as construction works are taking place adjacent to a major burn whereby people, machinery and materials would be at risk is very low. Post-mitigation, the proposed works are not expected to lead to any changes in the hydrological regime of the watercourses within or downstream of the proposed development. Therefore, on this basis of probabilities, and in consideration of proposed mitigation, the magnitude of any impact on flood risk is considered to be Minor. Therefore the overall residual impact in terms of flood risk is predicted to be Minor and not significant.

Underground Cable

10.7.13 Works on the underground cabling element of the Proposed Development would not commence in advance of proposed methodologies, (and any associated required mitigation), being agreed with SEPA and THC.

10.7.14 An assessment of residual effects post-consideration of the required mitigation is set out below. No significant potential residual impacts on geology, hydrology and hydrogeology as a result of the installation of the underground cabling have been identified.

POTENTIAL IMPACTS OF ENGINEERING WORKS IN THE WATER ENVIRONMENT

10.7.15 As discussed above, the alignment of the underground cable elements of the Proposed Development avoids identified instances of GWDTE where ever possible. The underground cable element does however cross one short (<500 m length) of potential GWDTE at Hollandsmey Moss which, based on the NVC classification, is considered of moderate sensitivity (see Figure 7.4). However as a result of existing agricultural land practices of draining and grazing, this habitat is considered likely to be of low ecological value for GWDTE (see chapter 7: Ecology).


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10.7.16 In addition, mitigation measures to be incorporated within the CEMD and supporting CEMP, and as set out within Chapter 11: Soils, Land Use and Agriculture specifically relating to the management of peat will be confirmed as appropriate. These will be confirmed in association with further detailed construction methodology information submitted by the Principal Contractor as part of CAR licence application to SEPA, prior to any construction commencing.

10.7.17 The Proposed Development crosses a number of watercourses and other sensitive receptors including a small number of instances of potential GWDTEs (further information is provided with Chapter 7: Ecology). Works would not commence in advance of the proposed construction methodologies incorporating required mitigation as set out within the CEMD and supporting CEMP, being agreed with SEPA and THC. It is reasonably assumed that a CAR Licence would not be granted unless any potential impacts would be of minor magnitude after consideration of proposed methodologies and associated mitigation.

Whilst the sensitivity of some identified receptors is High, following the implementation of identified mitigation measures and the successful receipt of a CAR Licence for all licensable activities, the magnitude of any impact on surface features and areas of GWDTE is considered to be Minor.

The overall impact is predicted to be Minor and therefore not significant in EIA terms.

POTENTIAL IMPACTS ON LOCAL HYDROLOGICAL FLOW

10.7.18 Following the implementation of mitigation measures described, in particular ensuring that flows in watercourses and ditches would be maintained such that there is no flow restriction or increase in conveyance either up or downstream of any works, the magnitude of any impact on surface water flow is considered to be Minor. For both water courses identified as having a High sensitivity and those identified as having a Moderate sensitivity, as discussed in Section 10.5, the overall residual impact as a result of engineering works in the water environment is expected to be Minor and not significant.

POLLUTION IMPACTS

10.7.19 Surface runoff containing silt, and pollutants such as fuel and other contaminants used during construction, has the potential to enter watercourses in the vicinity of works thereby temporarily impacting on water quality and the hydrological and ecological function of receiving watercourses. Following the implementation of mitigation measures described above, the magnitude of any impact on all watercourses is considered to be Minor. For both watercourses identified as having a High sensitivity and those identified as having a Moderate sensitivity, as discussed in Section 10.5, the overall residual impact is expected to be Minor and not significant.


10.7.20 The underground cable element would have the potential to detrimentally affect the structural integrity of watercourse banks, in particular at watercourse crossings. Following the implementation of mitigation measures described above, such as ensuring any diversions of watercourses are subject to restoration across the full working width of the watercourses, the magnitude of any impact on all watercourses is considered to be Minor. The sensitivity of watercourse banks is


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identified as Medium-High; therefore, the overall residual impact is expected to be Minor and not significant.

DISRUPTION TO ARTIFICIAL DRAINAGE

10.7.21 Localised damage to existing land drainage could occur as a result of the underground cable element of the Proposed Development. Land drainage is considered to be of local importance and therefore Low sensitivity. Following the implementation of mitigation measures, the magnitude of any impact on local land drainage is considered to be Negligible. Therefore the overall residual impact on land drainage is predicted to be Negligible and not significant.

DEWATERING OF TRENCH EXCAVATIONS

10.7.22 Surface waters generated as a result of dewatering of the trench for the underground cabling element could have a potential impact on groundwater and surface water conditions; both in terms of flow disruption and mobilisation of sediments.

10.7.23 Following the implementation of mitigation measures described, the magnitude of any impact on all watercourses is considered to be Negligible. For both water courses identified as having a High sensitivity and those identified as having a Moderate sensitivity, as discussed in Section 10.5, the overall residual impact as a result of dewatering is expected to be Minor and not significant.


10.7.24 No significant potential residual impacts on geology, hydrology and hydrogeology as a result of the operation of the Proposed Development have been identified.


10.8.1 Chapter 3: EIA Methodology identifies other developments to be considered for potential for cumulative impact with the Proposed Development. Even in the event that these other developments present potentially significant impacts to the receiving geological, hydrogeological and hydrological environment, no significant residual impacts from the Proposed Development have been identified. Therefore no significant cumulative impacts are anticipated.





Construction

Potential Impacts on Geology

None required. N/A No residual impact

Potential Impact of Engineering Works in the Water Environment

Contractor will identify all receptors and potential discharge locations prior and appropriate pollution control measures will

CEMP

DMP

No significant residual impact on watercourses


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be installed prior to works. Emergency response procedures will be established.

GWDTEs have been avoided where feasible. Where access tracks will be required to pass through GWDTE, floating road techniques will be adopted.

Route selection

Detailed design

No significant residual impact on the hydrological regime of GWDTE

Pollution Impact from Silt-laden Runoff

Sediment control measures and emergency response planning will developed and adopted prior to works in conjunction with detailed drainage design.

CEMP

DMP

No significant residual impact

Pollution Impact from Chemical Contaminated Runoff

Potential polluting materials will be stored in accordance with best practise. Pollution control measures and emergency response planning will developed and adopted prior to works in conjunction with detailed drainage design.

CEMP

DMP


Impact on Integrity of Banking

Micro siting of Proposed Development will avoid watercourses where possible.

Watercourse crossings will be designed such that flow regimes and bank integrity are not affected.

Where works near water are required detailed method

DMP

Detailed Design



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statements will be produced such that flow regimes, erosion and sediment transport regimes are not affected.

Direct Discharge of Untreated Foul Drainage

Discharge will be to portable septic tank or to foul sewer.

N/A None

Disruption to Artificial Land Drainage

All existing drains will be identified by the contractor prior to works.

Where works near watercourses or drains are required detailed method statements will be produced such that impacts on flow regimes, erosion and sediment transport regimes are minimised.

CEMP

DMP

Detailed design


Dewatering of Foundation Excavations

Measures for the management, removal and disposal of any water ingress into excavations will be adopted such that impacts on the integrity and water content of the surrounding ground is minimised.

CEMP No significant residual impact

Flood Risk The Proposed Development has been sited to avoid floodplain areas wherever feasible.

Construction within floodplains would be undertaken during the driest (summer). Excavations would be dug and left open for the minimum of time.

Routing study

CEMP



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Construction works would not take place during extreme weather conditions or in floodplain areas that are inundated. In such circumstances, contractors would move all heavy plant out of identified risk areas.

The Proposed Development itself is not considered to be vulnerable to flood risk.

Operation

None anticipated N/A N/A N/A





Construction

Runoff of sediment (including waste from forestry works or soils/ peats) from works into watercourses.

Ensuring there is no pollution of watercourses or ditches during works from sediment during excavation, or chemicals - for example, scour protection and silt management measures would be installed at the discharge of any temporary diversion.

CEMP

CAR Licence


Direct pollution of watercourses during engineering works in the water environment.

Spillage or leakage of fuels, oils and lubricants from machinery, plant or materials used in

Potential polluting materials will be stored in accordance with best practise. Pollution control measures and

CEMP

CAR Licence



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construction operations.

emergency response planning will developed and adopted prior to works in conjunction with detailed drainage design.

Changes in hydrological flow caused by watercourse crossings.

Flows in watercourses and ditches would be maintained such that there is no change to hydrology either up or downstream of any works, i.e. no significant flow restriction or increase in conveyance.

CEMP

CAR Licence


Operation

None anticipated N/A N/A N/A


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LT000022 11-1 Chapter 11:

Soils, Land Use and Agriculture

11 SOILS, LAND USE AND AGRICULTURE

11.1 Introduction

11.1.1 This chapter considers the potential impacts on soil resources and land use with particular emphasis on agricultural land as a result of the construction and operation of the Proposed Development.


characterise the baseline in terms of soil resource, land use and agriculture. For the purpose of this assessment use considerations are limited to primary industrial activity (i.e. agriculture, forestry, extractive industry, and primary energy generation);

investigate the presence/possible presence of sensitive soils, including peat within the study area;

describe the likely potential impacts, including direct, indirect, secondary and cumulative impacts as a result of the Proposed Development both during construction and operation in terms of impacts on soils, land use and agriculture;



11.1.3 Supporting data for the assessment provided in this chapter can be found in Technical Appendix 11.1 and also where appropriate, in Technical Appendix 7.1 relating to Ecology and Nature Conservation.

11.1.4 This chapter and impact assessment described within has been undertaken by Maeve Fryday BA (Hons), MSc of Ramboll Environ UK Limited (Ramboll Environ).


11.2.1 The assessment of potential impacts on soils, land use and agriculture has been undertaken in accordance with the relevant policy and guidance as described below.


Scottish Planning Policy (2014)

11.2.2 SPP includes the following policy relevant to soils and land use.

11.2.3 Where it is necessary to use good quality land for development, the layout and design should minimise the amount of such land that is required. Development on prime agricultural land, or land of lesser quality that is locally important should not be permitted except where it is essential:

as a component of the settlement strategy or necessary to meet an established need, for example for essential infrastructure, where no other suitable site is available; or

for small-scale development directly linked to a rural business; or


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Chapter 11: Soils, Land Use and Agriculture 11-2 LT000022

for the generation of energy from a renewable source or the extraction of minerals where this accords with other policy objectives and there is secure provision for restoration to return the land to its former status.

Getting the best from our land - A land use strategy for Scotland (2011)

11.2.4 Some types of land have particular value in delivering benefits of key strategic importance, helping to ensure that we continue to meet our long‐term needs. For this reason we have policies in place to safeguard such types of land against inappropriate use. For example, in support of our goals on food security, we should continue to ensure that our prime agricultural land retains its capacity for food production.

Regional Policy

Highland-Wide Local Development Plan

11.2.5 The Highland wide Local Development Plan is largely silent on the subject of soils and agricultural land use, with the exception of issues relating to crofting.

11.2.6 Policy 47 Safeguarding In-bye/Apportioned Croftland sets out the Council’s requirements for protection of crofting through a policy which requires consideration of potential effects on crofting enterprises where development that could reduce the extent and utility of a landholding is proposed. Although this policy primarily relates to dwelling house developments, there are key considerations under this policy of relevance to the Proposed Development including:

avoid siting on the better part of a croft in terms of its agricultural value; and

avoid impeding use of the remaining croft land by virtue of its location.

11.2.7 Similarly, the interests of the wider community may be recognised as a compelling factor in favour of development under this policy, where:

there is no alternative viable land (outwith in-bye land/apportioned croft land); and

the proposal brings significant economic or social benefits to the community as a whole.


11.3.1 Table 11.1 below summarises the issues identified during the consultation process that are of relevance to soils and agriculture.



SEPA For areas where avoidance is impossible, details of how impacts upon wetlands including peatlands are minimised and mitigated should be provided within the ES or planning submission. In particular impacts that should be considered include those from drainage, pollution and

Extended Phase 1 Habitat Survey and a targeted National Vegetation Classification (NVC) have been undertaken in order to identify location and extent of potential wetland habitats and GWDTE as set out within Chapter 7 of this ES.

Potential impacts on peatland hydrology, drainage and pollution risk


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waste management. This should include preventative/mitigation measures to avoid significant drying or oxidation of peat through, for example, the construction of access tracks, dewatering, excavations, drainage channels, cable trenches, or the storage and reuse of excavated peat.

have been consider as set out within Chapter 10 of this ES.

A detailed peat management plan will be developed, if required, by the Principal Contractor, prior to construction commencing.

Commitments required to be incorporated into a detailed peat management plan are set out within section 11.6 of this ES.

SEPA Peat disturbance and re-use: A Peat Management Plan should be included within the Environmental Statement (prior to the application gaining consent) which sets out the principles as to how any surplus peat will be managed within the site.

All proposals for peat management are to be in accordance with Guidance on the Assessment of Peat Volumes, Reuse of Excavated Peat and Minimisation of Waste and our Regulatory Position Statement – Developments on Peat.

Chapter 4 of this ES summarises the process of iterative design development which has been delivered, including, in order to minimise the requirement for either OHL or underground cable to cross extensive areas of deep peat (>1m depth)

Nonetheless, commitments required to be incorporated into a detailed peat management plan in the areas where disturbance to peatland may occur are set out within section 11.6 of this ES.

A detailed peat management plan, including peat depth survey will be completed following micrositing to confirm localised areas of peat by the Principal Contractor, prior to construction commencing.

Marine Scotland All construction should avoid areas of deep peat and where this is not possible appropriate mitigation measures should be put in place.

Natural peat drainage channels should be preserved throughout the development; excavated material should not be stock piled in areas of unstable peat; concentrated water flows onto peat slopes should also be avoided.

See above.



11.4.1 Consideration has been given to the detailed mapped soil resources overlain by the Proposed Development, with separate consideration given to the soils present


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in the area of the Proposed Development to be undergrounded and the area to be delivered as an OHL.

Desk Study

11.4.2 The following published mapping along the Proposed Development has been reviewed in order to identify the anticipated current agricultural and soil resource at the site:

Soil types (to Soil Series level)1; and

Land Capability for Agriculture2.

11.4.3 The memoirs3 published to support the soils maps for this area have also been consulted in determining baseline conditions in the area of the Proposed Development.

11.4.4 In addition, the findings of the Phase 1 Habitat survey as presented in Chapter 7: Ecology have been used to supplement this information, in particular where mapped habitat indicates possible presence of peat and where bog conditions prevail which are indicative of actively forming peat.

11.4.5 The current land use in the area of the Proposed Development has been determined through walkover survey conducted during the ecological surveys.


Impact Assessment

11.4.6 Professional judgement has been used to establish the value (sensitivity) of existing soil resources, quality of soils for agricultural purposes, agricultural land holdings and agricultural and other primary land use activities typical in the area. This has been supported through available guidance where appropriate including Institute of Ecology and Environmental Management (IEEM) best practice assessment guidelines4.

Sensitivity (Value) of Receptor

11.4.7 Sensitivity of individual receptors has been defined in terms of high, medium or low sensitivity.

11.4.8 The sensitivity of individual soils, land use and agriculture receptors i.e. its baseline quality as well as its ability to absorb the effect is defined in Table 11.2.

1 The Macauley Institute for Soil Research, 1970. Soil Survey of Scotland - Systematic Soil Survey, Latherton and Wick Sheets

110 and 116 and part of Sheet 117 (SOIL) 12, 1:63,360 scale. The Macauley Institute for Soil Research, Aberdeen. 2 Soil Survey of Scotland, 1987. Land Capability for Agriculture, Thurso and Wick Sheet 12, 1:50,000 scale. The Macauley

Institute for Soil Research, Aberdeen. 3 The Macauley Institute for Soil Research, 1976. The Soils of the Country Round Wick. The Macauley Institute for Soil

Research, Aberdeen. 4 IEEM (2006) Guidelines for Ecological Impact Assessment in the United Kingdom, IEEM, Winchester.


LT000022 11-5 Chapter 11:


Table 11.2: Definition of Sensitivity of Soils, Land Use and Agriculture

Sensitivity Definition

Very high International importance. High quality and rarity, regional or national scale and limited potential for substitution/replacement.

High National importance. Receptor with a high quality and rarity, local scale and limited potential for substitution/replacement or receptor with a medium quality and rarity, regional or national scale and limited potential for substitution/replacement.

Medium Regional importance. Receptor with a medium quality and rarity, local scale and limited potential for substitution/replacement or receptor with a low quality and rarity, regional or national scale and limited potential for substitution/replacement.

Low Local importance. Receptor with a low quality and rarity, local scale. Environmental equilibrium is stable and is resilient to changes that are greater than natural fluctuations, without detriment to its present character.

11.4.9 The application of the sensitivity criteria set out in Table 11.2 has had regard for the following considerations:

the quality of soils, in terms of Land Capability for Agriculture (LCA): While there is no longer a statutory protection for best and most versatile soils, the retention of good quality agricultural land remains an important consideration. The sensitivity of this aspect considers the LCA of land in the context of the location where climatic factors are severely limiting and where land which elsewhere may be considered of limited value may be locally more important;

the extent of agricultural holdings: Sensitivity of agricultural land holdings is considered within the context of known land ownership, assumed connectivity between fields and farm infrastructure, including access to farm yards and sensitivity to potential fragmentation and isolation;

farming practices: the sensitivity of farming practices is considered within the context of disruption to field drainage systems and temporary access restrictions; and

other land uses: the sensitivity of other primary land uses is considered in terms of the potential for the Proposed Development to restrict operations (e.g. forestry operations, wind farm operation).

11.4.10 It should be noted that for the purposes of this assessment, land use has not been taken to include recreational or access (i.e. public roads) issues. These issues are considered in Chapter 12: Traffic and Transport.

Magnitude of Effect

11.4.11 The magnitude of effect includes timing, scale, size and duration of the potential effect. This is defined in terms of Major, Moderate, Minor or Negligible magnitude. Impact magnitude is defined in Table 11.3.


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Table 11.3: Magnitude of Effect

Magnitude Definition

Major Results in loss of attribute. Fundamental (long term or permanent) changes to soil, land use and/or agriculture.

Moderate Results in effect on integrity of attribute or loss of part of attribute. Material but non-fundamental and short to medium term changes to soil, land use and/or agriculture.

Minor Results in minor effect on attribute. Detectable but non-material and transitory changes to soil, land use and/or agriculture.

Negligible Results in an effect on attribute but of insufficient magnitude to affect the use/integrity. No perceptible changes to soil, land use and/or agriculture.


11.4.12 The sensitivity of the receiving environment together with the magnitude of the effect defines the significance of the effect as outlined in Table 11.4.


Magnitude

Receptor Sensitivity

Major Moderate Minor Negligible

Very High Major Moderate Minor Not significant

High Major Moderate Minor Not significant

Medium Moderate Moderate Minor Not significant

Low Minor Minor Not significant Not significant

11.4.13 The application of the significance criteria set out in Table 11.4 specifically to soils, land use and agriculture has been supplemented by professional judgement.

11.4.14 The assessment of soil resources seeks to identify and quantify the soil resource present and then determine what loss of soil, including peat (greater than 1 m in depth) may be expected to occur as a result of the Proposed Development. The potential disturbance of soils in the course of the construction of the Proposed Development is also considered in order to identify a set of soil management measures to ensure loss of and damage to soil is avoided or minimised.


11.5.1 The following sections set out the current conditions, in terms of soil resources present, LCA, land holdings and land uses along the Proposed Development.

Current Baseline

Current soil resources and LCA

11.5.2 The current soil resources along the Proposed Development are mapped at the soil association and soil series levels as summarised below and described in Technical


LT000022 11-7 Chapter 11:


Appendix 11.1 (Table 1: Soil Association; Table 2: Soil Series). Soil resources present (at soil series level) are described for sections of the LOD as described in Chapter 4: Description of Development.

11.5.3 These soil series confirm the presence of predominantly mineral soils along the Proposed Development, occurring along 54.5% of the cable sections and 65.5% of the OHL sections, reflecting the nature of the parent material, a mix of drift deposits derived from sedimentary rocks and solid deposits typified by Old Red Sandstone (ORS) Caithness Flagstones, mineral soils are predominantly loam and sandy loam in texture.

11.5.4 Peaty gley and peaty podzol soils are also mapped along the Proposed Development and these are organic soils (i.e. soils with strong humic horizons, particularly at their surface) rather than indicative of actively forming bog conditions, and are properly considered as dominated by their mineral fractions when considered as a soil unit. Organic soils occur along 26% of the cable sections and 10.5% of the OHL sections.

11.5.5 The soils along the remainder of the Proposed Development are mapped as peat, with 19.5% of the cable sections and 24% of the OHL sections identified as crossing areas of peat.

11.5.6 Deep peat (>1 m in depth) is mapped only in the area of the Moss of Greenland and Hollandmey Moss (generally Sections H to M), with 11% of the cable sections and 11% of the OHL sections identified as crossing areas of deep peat. Limited published information is available regarding the nature of the peat deposits, and actual depths present, in this area. The Moss of Greenland area is described as peat mainly derived from a sedge-carr community, with most of the oligotrophic peat (nutrient poor) removed by cutting. Depths are described as varying between 0.9 and 1.8 m, although evidence from banks suggests depths may originally have exceeded 3 m, with surface vegetation similar to virgin blanket.

11.5.7 Some of the prevalent soil series are described as relatively shallow, with overall soil depths varying between 20 cm (Bilbster – shallow) and the majority of the soil series present extend to 100 cm+.

11.5.8 Topsoils vary in composition from shallow (10 cm) humified fibrous peaty humus (Olrig), to moderate depths (25 cm) of loam (Thurso).

11.5.9 Subsoils are absent from some series (Bilbster - shallow) and extend beyond 100 cm across many of the series present. Subsoils are generally slowly permeable below approximately 35 – 45 cm bgl, resulting in overall poor drainage conditions despite good drainage characteristics across many of the shallow soils present.

11.5.10 The drainage characteristics of the area have led to extensive ‘improvement’ of land by installation of artificial drainage. The nature of the field drainage installed is not known, however it is likely to be a combination of traditional clay filled drains and more modern piped drainage. Further consideration of land drainage is given in Chapter 10: Geology, hydrogeology and hydrology.

11.5.11 The LCA classes present are 32 and below (Table 11.5) indicating that no prime agricultural land (i.e. LCA 31 or better) is present within the Proposed Development.


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Table 11.5: LCA Class & Division Details

LCA Class & Division

Class Description

Division Description

32 Land capable of producing a moderate range of crops.

The land is capable of average production but high yields of barley, oats and grass are often obtained. Other crops are limited to potatoes and forage crops. Grass leys are common and reflect the increasing growth limitations for arable crops and degree of risk involved in their production.

41 Land capable of producing a narrow range of crops.

Land in this division is suited to rotation which, although primarily based on ley grassland, includes forage crops and cereals for stock feed. Yields of grass are high but difficulties of utilisation and conservation may be encountered. Other crop yields are very variable and usually below the national average.

42 Land capable of producing a narrow range of crops.

The land is primarily grassland with some limited potential for other crops. Grass yields can be high but difficulties of conservation or utilisation may be severe, especially in areas of poor climate or on very wet soils. Some forage cropping is possible and, when the extra risks involved can be accepted, an occasional cereal crop.

52 Land capable of use as improved grassland.

Sward establishment presents no difficulties but moderate to low trafficability5, patterned land and/or strong slopes cause maintenance problems. Growth rates are high and despite some problems of poaching, satisfactory stocking rates are achievable.

53 Land capable of use as improved grassland.

Land in this division has properties which lead to serious trafficability and poaching difficulties and although sward establishment may be easy, deterioration in quality is often rapid. Patterns of soil, slope or wetness may seriously interfere with establishment and/or maintenance. The land cannot support high stock densities without damage and this may be serious after heavy rain even in summer.

63 Land capable of use only as rough grazing.

The vegetation is dominated by plant communities with low grazing values, particularly heather moor, bog heather moor and blanket bog.

Source: Soil Survey of Scotland, 1987

11.5.12 The LCA divisions represented along the Proposed Development are characteristic of the Caithness area, with the north of Scotland limited in terms of LCA by climatic factors. The identified physical characteristic of the soils present extensive limitations to agricultural production as a result of wetness (expressed as field capacity days (FCD)), localised limitations to agricultural production are also present as a result of soils, gradient and micro-climatic conditions.

11.5.13 The LCA divisions present do not represent the most versatile land available to agriculture in Scotland. Agricultural land along the Proposed Development is

5 The potential of the terrain to support traffic


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predominantly of limited agricultural value however it does support grazing land and some arable uses to a locally important degree.

11.5.14 A small proportion of the land along the Proposed Development is LCC 32 (Section E-F). This LCC is generally coincident with the intermediate depth Bilbster series soils and can be considered important in a local context.

11.5.15 Overall the agricultural land along the Proposed Development is considered of low sensitivity.

Land Holdings

11.5.16 There are 26 landowners along the Proposed Development and the land is farmed as approximately 26 units, with 1 landowner engaged in forestry rather than agriculture. The overall landholdings within these farm units in the vicinity of the Proposed Development (that is contiguous land owned and land within 2 km) vary in size from <80 Ha to >300 Ha. The majority of these holdings are involved in livestock farming, with improved, semi-improved and unimproved/rough grazing land dominating the observed agricultural operations. A small proportion of the land holdings are used for arable production, with fields of barley and oats observed during site survey. (Chapter 7: Ecology and Nature Conservation).

11.5.17 Other land uses identified along the Proposed Development include small areas of forestry at Fryster and in the immediate vicinity of the proposed Gills Bay substation. Two wind farms are currently proposed along the Proposed Development, at Tofts of Tain and Earl’s Cairn. The planning boundaries of the proposed wind farms, though not the turbine locations, are within the LOD of the Proposed Development, as shown in Figure 3.1. Both of these proposed wind farms are at pre-application stage and there is no information available as to their likely final form in the event that planning consent is granted.

Future Baseline

11.5.18 In the absence of the Proposed Development, it is considered likely that the existing pattern of soils and LCA would remain largely unchanged, with the current level of agricultural influence being maintained through on-going agricultural land management practices. Should agricultural practices change in the future there may be some reduction in agricultural land quality where artificial drainage and agricultural improvement of land is discouraged by policy and incentives are provided for lower input farming practices. In common with much of the UK agricultural sector, it is likely that land holdings would consolidate over time, as operating margins become increasingly difficult to maintain and traditional farming practices decline.

11.5.19 With declining agricultural use it is likely that there would be an increase in plantation forestry. However, it is likely that forest and woodland cover within the area will remain generally constant in the vicinity of the Proposed Development given the lack of suitable locations; where plantation might arise this could represent a reduction in available agricultural land for grazing.


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OHL


11.6.1 Potential impacts on soils land use and agriculture associated with the construction of the OHL elements of the Proposed Development are identified below:

impacts on soils through loss as a result of excavations for foundations and Sealing End Compounds (SECs), and removal of excess soil;

loss of peat volume;

potential release of carbon dioxide due to disturbance of peat;

changes in soil quality arising from mixing of soils;

changes in soil quality due to mixing of peat with other soils;

changes in nutrient status of soils during storage, including release of nutrients form stored soils with potential to impact on water quality;

changes in suitability of soils to support certain habitat types;

disruption to agricultural activity including access restrictions during construction works;

fragmentation of agricultural holdings;

isolation and severance of agricultural land from wider land holdings; and

restrictions on areas available for future forestry planting and management operations.


11.6.2 Potential operational impacts associated with the construction of the OHL element of the Proposed Development would include disruption to agricultural and other land users’ activity (e.g. access restrictions for planned maintenance and in emergencies).

Underground Cable


11.6.3 Potential impacts on soils land use and agriculture associated with the construction of the underground cable elements of the Proposed Development are identified below:

impacts on soils through loss as a result of excavations for trench and removal of excess soil;

loss of peat volume;

potential release of carbon dioxide due to disturbance of peat;

changes in soil quality arising from mixing of soils;

changes in soil quality due to mixing of peat with other soils;

changes in nutrient status of soils during storage, including release of nutrients form stored soils with potential to impact on water quality;

changes in suitability of soils to support certain habitat types;


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disruption to agricultural activity including access restrictions during construction works;

fragmentation of agricultural holdings;

isolation and severance of agricultural land from wider land holdings; and

restrictions on areas available for future forestry planting and management operations.


11.6.4 Potential operational impacts associated with the construction of the underground aspect of the Proposed Development would include disruption to agricultural and other land users’ activity (e.g. activity restriction such as limitations on use of land to avoid potential cable disturbance, access restrictions in emergencies).

11.7 Mitigation


11.7.1 Mitigation by design, has been an integral part of the overall design strategy for the Proposed Development and a positive, pro-active approach has been adopted at each stage of the project, designed to avoid areas of sensitive soil resource where ever possible. The process is described and discussed further in Chapter 4: Route Selection and Alternatives.


11.7.2 The mitigation designed into the Proposed Development to minimise impact on soil resource would also ensure integrity of existing LCA class.

11.7.3 As noted in Chapter 2: Description of Development, three different approaches to forming tower foundations may be used, subject to final detailed design. These comprise:

spread type e.g. concrete pad and chimney;

piled type e.g. driven concrete, tube and micro pile; and

augered.

11.7.4 For the Proposed Development, the majority of tower foundations are likely to be of a spread type, which would be approximately 50 cm deep, buried to depths of between 2.5 and 4 m, and extending over an area suitable to deliver the loading characteristics required (which would be a function of the underlying ground conditions and the weight of the structures to be supported).

11.7.5 Piled foundations may be required where low strength ground conditions are expected such as in areas where peat in excess of 1 m depth may be encountered. Detailed geotechnical investigation at each proposed tower location during micrositing will be required to determine local conditions especially where peat is present and to confirm depth of peat where encountered. Similarly, the alluvium present along the Proposed Development is mapped as being variable in composition and local conditions at individual tower locations would be subject to detailed appraisal prior to construction to determine foundation requirements.

11.7.6 It is anticipated that piled foundations may be required in the areas of the Moss of Greenland and Hollandmey Moss.


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11.7.7 The construction of the SECs at Weydale and north of Reaster (as shown on Figure 2.1 and 2.3) would be constructed to minimise damage to the soil structure. They were located in areas of grassland (Figure 7.3a and c) to avoid the requirement to disturb areas of deep peat.

Access Tracks

11.7.8 Access will be required to construct the towers and string conductors. Whilst the detailed access requirements have not been finalised, an indicative access strategy is set out within Chapter 2: Description of Development.

11.7.9 However, accesses will be constructed within the LOD defined in Figures 2.1 to 2.5. Proposed accesses have been selected with preference being given to using existing tracks which would be upgraded and to locating new access roads along field boundaries.


11.7.10 In addition to the mitigation by design measures noted above, the underground cable route has sought to avoid areas of peat of >1m depth, and crossings of infrastructure as far as possible. These measures minimise the potential for impacts on soil resources and potential for severance or fragmentation of farm units during construction.

11.7.11 The proposed cable trench depth is anticipated to 1.4m bgl, depending on local conditions including topography, gradient and ground conditions. A minimum cable depth of 1.1m is recommended to ensure that limitations to agricultural activities over the cable alignment will be avoided, given that the cable will be located below plough-depth and beyond the rooting zone of crops grown in the soils present (e.g. rooting depth will be restricted by depth of soils, presence of rock at shallow depth, and presence of compacted layers such as those which are characterised by slow permeability).


11.7.12 Mitigation during construction will largely be delivered by careful and controlled soil management, which would be similar for both OHL and underground sections, as outline below.

Mitigation during OHL & Underground Cable Construction – Soil Resources

11.7.13 Construction operations will adopt a strict system of quality control during any stripping and storage of the mineral soil types, i.e. those with a high organic fraction, and peat. This will enable conservation of soil resources for potential use elsewhere.

11.7.14 The successful reuse of soil resources will depend on preventing the structural deterioration of the mineral soils when they are handled. Deterioration can be reduced by soil movements taking place when the soils are not at Field Capacity, and preferably when each soil horizon or layer is drier than the Plastic Limit, as defined in BS 13776. However given the climatic conditions in the area some handling of soils which are at Field Capacity is unlikely to be avoidable and in such cases care would need to be taken to avoid unnecessary excavation and handling.

6 British Standards Institute, 1990. BS 1377:1990 Methods of test for soils for civil engineering purposes. BSI, London.


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PRODUCTION OF CONSTRUCTION ENVIRONMENTAL MANAGEMENT DOCUMENT AND SITE SPECIFIC

ENVIRONMENTAL MANAGEMENT PLANS

11.7.15 A Construction Environmental Management Document (CEMD) will be prepared defining the methodologies and management measures to be employed in the construction of the Proposed Development.

SOIL STRIPPING

11.7.16 Given the localised nature of the soil excavations required for tower construction and cable undergrounding, it is considered that the appropriate approach to soil management will be to strip soils with different characteristics separately as far as possible. This will be particularly the case in excavations to accommodate spread type tower foundations and undergrounding trench excavation, where the majority of the excavated soil will be replaced on completion of construction. Minimal surplus excavated soil is anticipated. The CEMD will detail the high level requirements for soil management and provide a mechanism for the mitigation measures below to be carried forward into the detailed CEMP for soil management. Specific measures for the management of soils include:

Mineral Topsoils: The loam and sandy loam topsoils to be stripped as a single unit and stored, either temporarily for replacement or transferred to a location identified for their longer term use in landscaping, as appropriate to protect against the potential degradation of the structure, particularly given that these soils are generally imperfectly-drained.

Organic Topsoils: Organic topsoils to be stripped from the underlying mineral subsoils, where they are of sufficient depth to allow separate stripping. Where these soils occur at thicknesses of less than 300 mm they would be stripped with underlying material as a single unit to ensure practical handling can take place. The resulting soils will be treated as organic topsoils and stored separately from mineral topsoils for reuse as a single unit, either as replaced soil around tower foundations or in locations identified for longer term use in landscaping.

Subsoils: The subsoils from the mineral soils would potentially be subject to structural degradation. Given the shallow depth of these soils above slowly permeable horizons (approximately 45 cm) it is most likely that the soils of this type will be excavated as a single unit rather than attempting to separate them out. The quality of these soils is such that no significant deterioration in quality will be expected to arise from mixing of horizons above slowly permeable layers. Similarly deeper subsoil horizons, including those which exhibit slowly permeable characteristics will be treated as a separate unit where practicable.

The over-arching mitigation, for all soil handling to be carried out in as dry conditions as practicable, will reduce the impact on the already poor quality slowly permeable subsoils.

SOILS STORAGE - MOUND DESIGN

11.7.17 No large scale or long term storage of soils in mounds is anticipated; however some temporary local storage at tower foundation excavations and at areas where cable trenching is occurring will be required to allow construction of the Proposed Development. Where such temporary soil storage is established both mineral and organic topsoils will be established on geotextile underlay (to protect underlying soils).


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11.7.18 The outer faces of the mounds would have gradients which minimise the risk of slumping and would take account of the underlying ground conditions, including topography and the nature of the mounding material. It is anticipated that soil storage at both tower locations and associated with cable trenching will be temporary and for no longer than a period of 4 weeks, if practicable. Soil stored for more than a 4 week period will be maintained to stabilise the mounds and reduce erosion.

Mitigation during OHL & Underground Cable Construction – Peat

11.7.19 Disturbance of peat (i.e. peat at thicknesses of greater than 500 mm) is expected to be limited as the Proposed Development avoids areas of peat as far as possible. Subsequent micrositing of individual towers will further seek to avoid peat deposits and in particular minimise location of towers on areas of deep peat.

11.7.20 The CEMP will include specific proposals regarding peat, including if necessary, a peat management plan (PMP). A peat management plan, if required, will include:

a peat depth survey including details of the basic peatland characteristics, including a breakdown of acrotelmic, catotelmic and amorphous peat. This will be reported in a detailed map of peat depths with the microsited elements of the Proposed Development overlain so it can clearly be seen how areas of deep peat have been avoided where ever possible;

a table showing where surplus peat will be generated and what the quantities will be;

a table showing what quantity of this surplus peat will be catotelmic and what quantity will be acrotelmic;

a map showing where any temporary peat storage areas will be located and how these storage areas, along with any associated access roads, avoid any watercourses, groundwater dependant terrestrial ecosystems or other sensitive areas. In addition details should be submitted of how the storage areas will be constructed, calculations demonstrating the need for these storage areas, how thick the peat will be stored, what types of peat will be stored and how the peat will be maintained fit for re-use; and

two separate tables demonstrating the principles of where acrotelmic and catotelmic peat will be re-used and approximately how much will be re-used including details of width and thickness.

11.7.21 Construction mitigation measures within the peat management plan will include:

where peat is to be removed it will be excavated using a tracked excavator;

tracks and trucks will only run on mineral soils below the peat or on site roads or established areas of hardstanding to avoid structural degradation of the peat to be recovered;

where possible peat will be excavated and emplaced directly to its final position, with turves removed separately and reinstated at the surface, to minimise loss of moisture and integrity of the peat. If this is not possible, a specific method statement and risk assessment for handling peat will be developed by the Principal Contractor. If localised storage of peat is required, efforts will be made to retain moisture in the peat as far as possible and where feasible peat ponds utilising plastic liners will be established to maintain water levels in peat awaiting reinstatement; and


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where towers are proposed in areas of peat, foundation design and installation will have regard to minimising the extent of peat excavation. This will be determined in terms of engineering requirements however any solution shall ensure that minimisation of peat excavation is fully considered.

PEAT STORAGE

11.7.22 The volumes of peat to be excavated in tower foundation construction or underground cable installation are not anticipated to be large given the low prevalence of deep peat along the Proposed Development and the design work completed to date which has sought to avoid known areas of peat as far as possible. In the event that tower locations on deep peat are unavoidable (i.e. where micrositing of towers cannot avoid deep peat) any peat excavation requirements will be limited by the proposed piled foundation design.

11.7.23 If localised storage of peat is required, water levels in the peat will be maintained as far as possible through use of peat ponds utilising plastic liners whilst awaiting reinstatement.

Mitigation during Construction - Agricultural Land Holdings

11.7.24 Some access restrictions to areas of agricultural land would be likely during construction; similarly agricultural activities may influence timing of certain construction works, in particular the lambing season.

11.7.25 The detailed construction programme would be determined in consultation with landowners and occupiers to ensure appropriate levels of access and activity can be achieved.

Mitigation during Construction - Other Land Uses

11.7.26 Some disruption/access restrictions to areas of land in use for forestry and/or proposed for future forestry will be necessary during construction.

11.7.27 Small areas of forestry have been identified along the Proposed Development, including Forestry Commission interests on the approach to the proposed Gills Bay Substation. Forestry operations (e.g. felling) may influence timing of certain construction works. A detailed construction programme will be determined in consultation with landowners and occupiers to ensure appropriate levels of access and activity can be achieved.


Soils & LCA

11.7.28 Operation of the Proposed Development (both OHL and underground cable aspects) is not anticipated to require any further mitigation of potential impacts on soils.

Agricultural Units & Other Land Users

11.7.29 Some access to areas around towers and the area within the underground cable wayleave will be necessary during operation of the Proposed Development. Wayleave rights of access will be held by the operator for ongoing maintenance and emergency access. Arrangements will be made with landowners and occupiers to, as far as practicable, arrange access across land in advance.


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Soils

11.8.1 The Proposed Development has sought to minimise the volumes of soil to be disturbed and removed and to ensure appropriate measures are in place to manage soils both where they are disturbed and to be reinstated over foundations and where they are to be removed permanently.

11.8.2 A working area of approximately 2500 m2 is anticipated for each tower location and SEC. Within this, and for assessment purposes, the preparation of spread type foundations for the towers over much of the Proposed Development have been estimated to require excavation of an area of approximately 2.5 m x 2.5 m for each tower footing (i.e. an area of 2.5 m x 2.5 m x 4 for each tower location). The two SECs will cover an area of approximately 40 m x 40 m each.

11.8.3 The depth of excavations is likely to extend below existing soil horizons, resulting in full excavation of soils present in the area of each foundation. The standard design of these foundations is such that much of the excavated soil will be replaced, with the volume to be replaced by the concrete pad and reinforced concrete ‘chimney’ being the only excess soil requiring removal. This will result in estimated excavation volumes along each of the Proposed Development as indicated in Table 11.6. These figures are considered reasonable worst case volumes, and are based on the volume of soil requiring removal being topsoil of 0.2 m of the ‘chimney’ height, with the remaining 0.8 m of soil depth along the chimney requiring removal of subsoil. It is assumed that the SECs would only require topsoil removal – excavations to lay cables within the SEC would require disturbance only.

Table 11.6: Estimated Indicative Excavation Volumes7

Angle Towers (m3) x 10

Suspension Towers (m3) x 40

Terminal Towers (m3) x 2

SECs (m3) x 2

Underground cable (m3)

Total (m3)

Excavated Topsoil

50 200 10 640 900

Excavated Subsoil

200 800 40 1040

Disturbed Topsoil

9,716 9,716

Disturbed Subsoil

38,864 38,864

11.8.4 These soil volumes are likely to be overestimates, particularly in areas where towers are excavated on shallower soils and competent strata are encountered at shallower depths. Residual impacts would relate to disturbance and loss of soil

7 These estimates have been based on an evaluation of volumes required to accommodate tower foundations. The proposed

access track design requires no extensive excavation of underlying soils although small scale excavation may be required in specific areas.


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associated with its removal to accommodate tower foundations and displacement by cable bedding material.

11.8.5 The overall volume of soil to be removed permanently represents a very small proportion of the available soil resource and is therefore considered of minor magnitude and low sensitivity. Reuse of this material elsewhere, where possible, will ensure its conservation in the long term. No significant impacts are identified.

11.8.6 Some loss of soil from agricultural production is expected within the associated works LOD. However, given the relatively small footprint of the areas of soil to be covered by potential new access tracks this loss is considered of minor magnitude and low sensitivity. No significant impacts are identified.

Land Capability for Agriculture

11.8.7 The construction of the Proposed Development is not anticipated to have any significant potential to impact on LCA in the area. The LCA is considered to be of low, and potentially occasionally moderate, sensitivity. The mitigation measures for management of soils which form part of the LOD of the Proposed Development will ensure no further deterioration in land quality, in particular in terms of soil availability and drainage characteristics. Minor magnitude of impact is anticipated. No significant impacts are identified.

Agricultural Land Holdings

11.8.8 Although loss of soil to agricultural use within the associated works LOD will occur, the associated works LOD follows existing tracks and field boundaries as far as practicable. Similarly the LOD of the Proposed Development has sought to avoid division of fields and separation or isolation of areas of land where possible. During construction there will be some disruption to agricultural activity, in particular restrictions on access to areas where construction works are underway. These disturbances and restrictions will be temporary, of relatively short duration and planned in advance with landowners and occupiers to limit the effect on agricultural operations.

11.8.9 The areas occupied by all 25 agricultural land owners have been reviewed along the associated works LOD. This review has concluded that the loss of land to access tracks, towers and restrictions on land use in the vicinity of the underground cable alignment will not result in a significant loss of land in the context of the individual farm units identified. The potential impact of land take for access tracks on land holdings are therefore considered of minor magnitude, given the size of the majority of the holdings affected and the likely extent of area of a given farm to be impacted at any one time. Where permanent access tracks are constructed or existing tracks upgraded (for operational and maintenance purposes, and to SECs – as outlined in Table 2.3), it is likely that the Proposed Development could improve farm access. The nature of the Proposed Development is such that no significant effects on isolation of areas of farm units is expected nor are any significant effects on permanent severance of existing access. Where permanent tracks are constructed for SECs for example, the overall effect on farm operations is considered to be potentially beneficial in terms of improved access roads within farms.

Other Land Uses

11.8.10 The Proposed Development would result in an impact of minor magnitude on land used for forestry. The design of the Proposed Development has sought to integrate


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with these land uses and share existing access infrastructure as far as possible. Further detailed design work to establish micro-siting of individual tower locations will continue to seek opportunities to use existing infrastructure and access arrangements to minimise impacts of disruption to these land users. No significant impact is anticipated.


Soils & LCA

11.8.11 Operation of the Proposed Development is not anticipated to have any significant residual effects on soils and LCA in the area of the Proposed Development.

Agricultural Holdings & Other Land Uses

11.8.12 The Proposed Development is anticipated to have a beneficial effect in terms of improved access to agricultural land. During the operational phase on-going access will be required for planned maintenance and in the event of emergencies. Where practicable these activities will be planned in advance with the landowner and occupier, however there may be instances when emergency access is required that may impact upon agricultural activities and forestry and wind farm operations. The effect of such disruption will be temporary and short duration and as such is not considered likely to constitute a significant effect.

11.9 Cumulative Impacts

11.9.1 No cumulative impacts are anticipated.

11.10 Summary

Table 11.7: Summary of Potential Impacts of the Proposed Development, Mitigation and Residual Impacts – OHL and underground cable

Likely Significant Impact

Mitigation Proposed Means of Implementation


Construction

Loss of soils as a result of excavation for foundations, SEC and/or cable trench and removal of excess soil from site

Minimise required excavations. Reinstatement of soils following installation of tower foundations; reuse of excess soils elsewhere

Mitigation by design and soil handling and storage measures will be set out within and implemented through the project specific CEMP

Not significant

Impacts on LCA as a result of loss of soil resource

Minimise required excavations. Reinstatement of soils following installation of tower foundations; reuse of excess soils elsewhere

Mitigation by design; and Soil handling and storage measures will be set out within and implemented through the project specific CEMP.

Not significant

Loss of peat volume Ensure avoidance/minimisation

Mitigation by design. Use of least

Not significant


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of activity within areas of peatland during construction

intrusive foundation design for small number of tower locations in identified peatland. Preparation and implementation of Peat Management Plans in areas where deep peat is encountered either by tower foundations or cable trenching

Release of carbon dioxide due to peat disturbance

Ensure avoidance/minimisation of activity within areas of peatland during construction

Mitigation by design. Use of least intrusive foundation design for small number of tower locations in identified peatland. Effective onsite management of peat and reinstatement in cable trench. Preparation and implementation of Peat Management Plans in areas where deep peat is encountered

Not significant

Changes in soil quality arising from mixing of soils

Separate soil handling and storage protocols for different qualities and types

Soil handling and storage measures will be set out within and implemented through the project specific CEMP

Not significant

Changes in nutrient status of soils during storage, including release of nutrients form stored soils with potential to impact on water quality

Minimise extent and duration of soil storage. Separate soil handling and storage protocols for different qualities and types

Mitigation by design (foundation design to minimise soil storage requirements) Soil handling and storage measures will be set out within and implemented through the project specific CEMP

Not significant


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Changes in suitability of soils to support certain habitat types

Minimise extent and duration of soil storage. Separate soil handling and storage protocols for different qualities and types

Mitigation by design (foundation design to minimise soil storage requirements). Soil handling and storage measures will be set out within and implemented through the project specific CEMP

Not significant

Disruption to agricultural activity including access restrictions during construction works

Timing of construction works and landowner agreements

Implementation through the project specific CEMP

Not significant

Impacts on agricultural holdings -Improvements to existing access tracks and creation of some new access tracks to SECs

No mitigation proposed Not applicable Beneficial

Disruption to forestry operations during construction



Not significant

Restrictions on areas available for forestry planting and management operations



Not significant

Operation

Disruption to agricultural and other land users’ activity

Timing of planned works and landowner agreements

Implementation through landowner agreements

Not significant


LT000022 12-1 Chapter 12:

Traffic & Transport

12 TRAFFIC AND TRANSPORT

12.1 Introduction

12.1.1 This chapter considers the potential impacts on traffic and transport as a result of the construction and operation of the Proposed Development.


characterise the baseline in terms of traffic and transport;

describe the likely potential impacts, including direct, indirect, secondary and cumulative impacts as a result of the Proposed Development both during construction and operation in terms of impacts on traffic and transport;



12.1.3 Supporting data for the assessment provided in this chapter can be found in Technical Appendix 12.1 and also where appropriate in Figures 12.1-12.3.

12.1.4 This chapter and impact assessment described within has been undertaken by Jordan Dunn of WYG.



Scottish Planning Policy, 2014

12.2.1 Scottish Planning Policy (SPP, June 2014) is a statement of Scottish Government Policy on land use planning. With respect to energy infrastructure developments and specifically transport, in subject policy A Low Carbon Place1, SPP indicates that Planning Authorities should consider impacts on road traffic and adjacent trunk roads but that considerations will vary relative to the scale of the proposal and area characteristics.

Regional Policy

Hitrans Regional Transport Strategy, 2008

12.2.2 The primary objective of the Highlands and Islands Transport Partnership (HITRANS) Regional Transport Strategy (RTS) is “to improve the interconnectivity of the whole region to strategic services and destinations in order to enable the region to compete and support growth.” It further states that the strategy’s overarching policy “is to develop a fit for purpose, multi-modal transport system.”

12.2.3 The RTS outlines ten horizontal themes where action and investment will be focused during the 15 year period following 2008. The themes relevant to the Proposed Development are:

1 Scottish Government (2014): Scottish Planning Policy.


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Chapter 12: Traffic & Transport 12-2 LT000022

development of a programme of investment to improve and maintain the locally significant rural road network which has suffered from under-investment in the past;

preparation of a strategy for investment in ports and ferries;

development of initiatives for reducing the cost of transport and travel; and

development of ways to reduce and mitigate the climate change impact of travelling in, to and from the region.

Local Policy

The Highland Wide Local Development Plan (HWLDP), 2012

12.2.4 The HwLDP deals with both strategic as well as local planning matters. Policy 28 states that, “The THC will support developments which promote and enhance the social, economic and environmental wellbeing of the people of Highland.”

12.2.5 Policy 28 goes on to state that proposed developments will be assessed on the extent to which they impact on approved routes for road and rail links.

12.2.6 Policy 67 states that The Highland Council (THC) will pay particular attention to any significant effects on ‘land and water based traffic and transport interests’.

The Caithness Local Plan 2002 (Retained Elements)

12.2.7 The Caithness Local Plan (CLP) seeks to create a growing population and expand the economy whilst improving communications and services and improving the environment. One of its strategic infrastructure objectives is to support the development of renewable energy in suitable locations within Caithness.

12.2.8 There are no policies within the CLP that are directly relevant to transportation.

The Highland Council Local Transport Strategy, 2010

12.2.9 The Local Transport Strategy (LTS) provides a direction for transport in the Highlands and the strategy “would guide policy and investment on transport within Highland THC” for the period 2011 to 2014. The LTS characterises the rural road network as ‘winding single carriageway roads with passing places’. THC manages a large number of bridges and has developed the ‘Lifeline Bridges Programme’ which ‘would invest in bridges to maintain access, remove weight restrictions or reduce the weight restriction effect of HGV vehicles’. The Lifeline Bridge programme is designed to ensure that heavy goods are able to continue to effectively move around the network and this is important for potential Abnormal Indivisible Load (AIL) movements throughout the area.

12.2.10 The LTS vision states that it seeks to “enable and facilitate sustainable development and economic growth”, with the objective that it would provide a transport network to enable sustainable economic growth.

Other Guidance

Institute of Environmental Assessment (IEMA) Guidelines for the Environmental Assessment of Road Traffic, 1993

12.2.11 The IEMA guidelines provide a reference for the assessment of the environmental impact of road traffic associated with major new developments. The purpose of the


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Traffic & Transport

guidelines is to provide the basis for a systematic, consistent and comprehensive appraisal of traffic impacts for a wide range of development projects. The guidelines are not intended to be exhaustive nor a reference for the very detailed or specific problems that occur in assessing the environmental impact of traffic. The guidelines are intended to complement professional judgment as the environmental impact of traffic will vary project by project.


12.3.1 A response was received in February 2014 from Transport Scotland in relation to the November 2013 Scoping Report. Further discussion with THC roads officers relating to access, traffic and transport effects was undertaken in April 2014. A summary of the consultation responses is included in Table 12.1 below.



Transport Scotland No issues raised N/A

The Highland Council

Concern regarding the volume of HGV traffic on fairly minor roads. Can the generated traffic be assigned to the routes proposed?

Table 12.10 assigns the predicted construction traffic across each of the surveyed locations.

Potential impacts from traffic and transport during construction include:

The possible requirement for localised road improvements, such as junction widening or road (culvert/drainage) strengthening, which may arise during the construction phase to accommodate HGV movements.

The potential for temporary effects on the amenity of residential areas and individual properties close to local roads, as a result of increases in HGV traffic.

The potential for temporary effects from HGV movements on the amenity of recreational users.

The consideration of potential impacts on vehicle flow on the road network, particularly on minor roads, where construction traffic would be routed. It is anticipated that vehicle numbers will be low however, if construction HGVs are using minor roads they may represent a large proportion of the overall traffic volume.

Issues concerning congestion, junction capacity, road safety and severance, and impacts on other road users during construction will be considered where appropriate.

This issue is discussed in the Mitigation section of this report.

This issue is addressed later in this chapter.

This issue is addressed in the wider EIA.

Consideration of traffic impact is given in sections 6 and 7 of Technical Appendix 12.1 and later in this Chapter.

Consideration of traffic impact is given in sections 6 and 7 of Technical Appendix 12.1 and later in this Chapter.

Issues Scoped out:


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Traffic movements during the operational phase are likely to be restricted to routine maintenance visits. No significant operational traffic impacts are anticipated.

Concern regarding the volume of HGV traffic on fairly minor roads. Can the generated traffic be assigned to the routes proposed?

The distribution of construction traffic is considered in Chapter 6 of Technical Appendix 12.1 and later in this Chapter.



12.4.1 This section sets out the methods used to characterise existing and/or future baseline conditions at the site and in the surrounding area and is based on site visits, review of published information/maps, consultation, policy review etc.

12.4.2 The study area, agreed with THC roads, comprises the parts of the public road network that could be used by construction and operational traffic accessing the Proposed Development. The roads identified as forming the likely route to the Proposed Development by construction traffic include the A9 / A836 / B874 / B876 / C1025 and U1727. Figure 12.1 illustrates the road network within the study area.

12.4.3 The public road network that could be used by construction traffic will also include numerous minor C/U Class routes that will provide access to the individual tower locations along with access to the underground cable section.

12.4.4 Baseline characterisation has sought to establish the nature of the surrounding road infrastructure and the current level of traffic that uses it. It has been informed by desktop studies and consultation, comprising the following:

review of responses to the scoping report;

collection of traffic flow data;

review of any roads hierarchy promoted in relevant Local Transport Strategies;

identification of sensitive junction locations;

identification of constraints to the roads network, with or without height/width/weight restrictions;

identification of areas of road safety concerns;

identification of other traffic sensitive receptors in the area (routes, communities, buildings etc.);

review of Ordnance Survey (OS) plans to derive a local area roads network; and

consideration of potential supply locations for construction materials, if not available on-site, to inform extent of local area roads network to be considered in the assessment.


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12.4.5 Field surveys have also been undertaken to further enhance the understanding of the road network in the study area and to identify potential constraints on the network, including:

visual inspection of all roads identified in the study area network;

photographic/video record of any constraints; and

Automatic Traffic Counts (ATC) to determine existing traffic flows on the surrounding road network.


12.4.6 The assessment has been undertaken in accordance with the Institute of Environmental Management and Assessment (IEMA) ‘Guidelines for the Environmental Assessment of Road Traffic’. The IEMA guidelines include details on how the sensitivity of receptors should be assessed. Using that as a base, professional judgement was used to develop a classification of sensitivity for various receptors. The guidelines also identify the key impacts that are most important when assessing the significance of traffic effects from an individual development: Table 2.2 of Volume 11, Section 2, Part 5 of the Design Manual for Roads and Bridges (DMRB) entitled ‘Assessment and Management of Environmental Effects’ sets out four levels against which the magnitude of these impacts should be assessed – major, moderate, low and negligible.



12.4.7 The receptors that may be subject to any traffic effects arising from the construction of the proposed development are likely to be settlements along the construction traffic route and the roads used by construction traffic. These settlements are classified by size, function, presence of school and community facilities, traffic calming or traffic management measures, vehicles speed limits and roads by their position on the roads hierarchy, using the criteria identified Table 12.2. This classification is based upon subjective professional judgement and relative sensitivity to the potential traffic effects of the Proposed Development.

12.4.8 Identification of receptor sensitivity requires the definition of current baseline conditions and also an estimation of conditions for the appropriate year of assessment. Each receptor will have a different value and level of sensitivity to change. Quantification of environmental impacts is easier for some receptors than others. Traffic noise has been extensively researched and methods of measurement developed. Other impacts such as severance are more subjective as there are no current proven or reliable techniques for study. Table 12.2 provides descriptions of receptor sensitivity based on DMRB guidelines HA 205/08 ‘Assessment and Magnitude of Environmental Effects.

12.4.9 For many effects there are no simple rules or formulae which define thresholds of significance and assessment has been made based of professional judgement, backed up by data or quantified information where possible.


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Table 12.2: Receptor Sensitivity

Receptor Negligible Low Medium High

Location Individual dwellings or scattered settlements with no facilities

Small rural settlement, few community or public facilities or services

Intermediate sized rural settlement, containing some community or public facilities and services

Large rural settlement containing a high number of community and public services and facilities

Road / Road Users

Roads with no adjacent settlements including new strategic trunk roads that would be little affected by additional traffic and suitable for Abnormal Loads

New strategic trunk road junctions capable of accommodating Abnormal Loads

Little or no traffic calming or traffic management measures

Trunk or A-class road, constructed to accommodate significant HGV composition

Some traffic calming or traffic management measures

Local A or B class roads, capable of regular use by HGV traffic

Traffic control signals, waiting and loading restrictions, traffic calming measures

Minor rural roads, not constructed to accommodate frequent use by HGVs

Magnitude of Impact

12.4.10 The IEMA guidelines identify general thresholds for assessment as traffic flow increases of 10% and 30%. The guidelines also suggest that 30%, 60% and 90% changes in traffic levels should be considered as “slight, moderate and substantial” impacts respectively with regard to severance and pedestrian perception of safety (intimidation). It is also considered by professional judgement that traffic flow increases of less than 10% are negligible, given that daily variation in background traffic flow may vary by this amount. Based on these guidelines and perceptions, the magnitude of the effect can be estimated for the traffic based effects using the criteria in Table 12.3.

Table 12.3: Impact Magnitude

High Medium Low Negligible

>90% increase in traffic

60% - 90% increase in traffic



Significance of Effect

12.4.11 To determine the overall significance of the effects, the results from the receptor sensitivity and impact magnitude classifications are correlated and classified using the scale summarised in Table 12.4.


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Table 12.4: Matrix for Determination of Significance of Effect

Sensitivity

Magnitude

High Medium Low Negligible

High Major Major Moderate Minor

Medium Major Moderate Minor Negligible

Low Moderate Minor Negligible Negligible

Negligible Minor Negligible Negligible Negligible

12.4.12 For the purposes of assessing significant effects, under the EIA regulations, this matrix provides a guide subject to professional judgement. For example, the introduction of a low number of additional HGV movements on a route that is currently subject to low numbers of HGV trips is recorded as being highly statistically significant, even though the numbers of additional trips could be five to ten additional vehicles. Despite the fact that additional traffic volumes may be exceptionally low, the effect may be statistically high. However, it is not necessarily significant in terms of the EIA regulations. Effects are considered to be significant for the purposes of the EIA Regulations where the effect is classified as being of equal to or greater than moderate significance.


Current Baseline

Study Area

12.5.1 The study area is shown on Figure 12.1 and detailed below.

12.5.2 The A9 trunk road is a strategic distributor road linking Caithness with the southern Highlands and central belt. The section of the road within the study area is single carriageway. As a result it is considered to be a receptor of low sensitivity.

12.5.3 The A836 is a non trunk THC category H1 strategic route running east to west along the northern coast line between Thurso and John O’Groats. The road is single carriageway along its entirety. As a result it is considered to be a receptor of low sensitivity.

12.5.4 The B876 is a rural distributor road running between Castletown and the A99 at Reiss. The road is single carriageway along its entirety. As a result it is considered to be a receptor of medium sensitivity.

12.5.5 The B874 is a rural distributor road running between Halkirk and the A99 at Wick Airport. Construction traffic is likely to utilise the single track section of the route between the A9 and the U2314. As a result it is considered to be a receptor of medium sensitivity.

12.5.6 The C1025 is a minor rural road running between the A836 and the C1048. Construction traffic is likely to utilise the section of the route between the U2188 and the U2196 with the aim of avoiding the urban section of the route adjacent to the A836. Other than the urban section of the route within Thurso the road is single


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track with passing places. As a result it is considered to be a receptor of high sensitivity.

12.5.7 The C1033 is a minor rural road running between the A99 and the B876. Construction traffic is likely to utilise the section of the route between the B876 and the C1006 at Greenland and a section south of the U1633. The road is single track with passing places along its entirety. As a result it is considered to be a receptor of high sensitivity.

12.5.8 The U1727 is a minor rural road running between the B876 and the C1006. The road is a single track with passing places in its entirety. As a result it is considered to be a receptor of high sensitivity.

12.5.9 Construction traffic is also likely to utilise sections of the following minor rural roads which are all single track with passing places and are considered to be a receptors of high sensitivity:

C1006;

C1048;

U2188;

U2196;

U2314;

U1731;

U1633; and

U1707.

12.5.10 The settlement of Thurso, through which the A9 and A836 passes, contains a large number of facilities. The facilities contained in the section of the town within the study area include, a supermarket, hotels, a school and a church. The town is considered to be a receptor of high sensitivity.

12.5.11 The rural settlement of Castletown, through which the A836 passes, contains a small number of facilities including local shops, a hotel, a school and a church. The village is considered to be a receptor of medium sensitivity.

12.5.12 There are a number of other scattered settlements without facilities within the study area which are considered to be receptors of negligible sensitivity.

12.5.13 All users of the roads are considered receptors subject to the same level of sensitivity as the route or location through which it passes, whichever is higher.

Traffic Volumes

12.5.14 In discussion with THC roads officers (see Table 12.1), seven sites were identified that would allow an accurate estimate of the potential impact of the construction phase to be made. To gauge existing usage, ATC surveys were commissioned at the following locations:

A836 east of the junction with the C1025;

A836 east of the junction with the B876;

C1025 east of the junction with the A836;

B876 south of the junction with the A836;


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B874 east of the junction with the A9;

C1033 south of the junction with the U1633; and

U1727 north of the junction with the B876.

12.5.15 The U1727 was selected as being representative of the minor road network within the study in terms of defining the likely impacts. Figure 12.2: Traffic Survey Locations, illustrates the proposed survey locations.

12.5.16 For each location, one week’s worth of count data was collected during May 2014 as agreed with THC Roads Department.

12.5.17 The traffic counters used allowed the traffic flows to be split into vehicle classes as well into overall directional traffic volume. The vehicle classes reported in the survey were as follows:

Motorcycles and pedal cycles;

Cars;

Lights – this classification covers light goods vehicles (up to 3.5 tonne) and cars with trailers/caravans;

Other goods vehicles – Class 1 (OGV1) & buses; this classifications covers smaller commercial vehicles between 3.5 and 7.5 tonnes and includes rigid 2 and 3 axle trucks and articulated trucks up to 3 axles as well as buses and coaches; and

Other Goods Vehicles – Class 2 (OGV2); this classification covers all HGVs with four or more axles.

12.5.18 Table 12.5 summarises the weekday traffic data collected at the seven sites.

Table 12.5: Existing Traffic Flows (Weekday Average Two Way Flows)

Survey Location Time Period Cars & Lights HGV (OGV1 + OGV 2)

Total

A836 east of C1025 12 Hours 3678 17 3716

24 Hours 4480 17 4512

A836 east of B876 12 Hours 1688 8 1708

24 Hours 2011 8 2031

C1025 south of A836 12 Hours 1971 10 1985

24 Hours 2649 15 2668

B876 south of A836 12 Hours 1548 14 1575

24 Hours 1875 15 1901

B874 east of A9 12 Hours 182 5 190

24 Hours 217 5 224

C1033 west of U1633 12 Hours 72 2 76

24 Hours 97 2 101

U1727 north of B876 12 Hours 107 1 109


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Table 12.5: Existing Traffic Flows (Weekday Average Two Way Flows)


Total

24 Hours 133 1 135

Traffic speeds

12.5.19 The ATC surveys were also used to collect speed statistics. The 5-day average2 and 85th percentile speeds3 observed at the count locations are summarised below in Table 12.6.

Table 12.6: Speed Summary (Weekday Average Two Way)

Survey Location Average Speed (mph) 85th Percentile Speed (mph)

Speed Limit

A836 east of C1025 31.5 35.1 30

A836 east of B876 33.6 37.8 60

C1025 south of A836 23.1 27.6 30

B876 south of A836 32.7 37.8 30

B874 east of A9 42.4 47.0 60

C1033 west of U1633

41.7 N/A 60

U1727 north of B874 42.7 N/A 60

Accident History

12.5.20 Road traffic accident data was obtained from THC Roads Department for the four years from the start of 2009 to the end of 2013at the following locations:

A9 between the B874 and the A836;

A836 between the A9 and Mey;

B786 between the A836 and the U1727;

B874 between the A9 and the U2314;

C1025 between the A836 and the U2314; and

The remainder of the C/U Class road network within the study area.

12.5.21 Table 12.7 below provides a summary of the 28 injury accidents recorded on the routes for the four year period.

2 The 5 day average was utilised in the assessment as the largest impact will be received during the working week. 3 Highways Agency (2008). Design Manual for Roads and Bridges. TA22/81 Vehicle Speed Measurements on all Purpose

Roads


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Table 12.7: Accident Data Summary

Location Severity No Vehicles / Peds

Vehicles Types Road Feature

Surface Condition Lighting

Slight

Serious

Fatal

Single

Multiple

Car +

Motorcycle

Car

Car +

Car

Car +

Pedestrian

Car +

Other

Car +

HG

V

Junction / Access

Pedestrian

Crossing

Dry

Wet or D

amp

Frost or Ice

Snow

Daylight

Darkness

A9 4 3 1 3 5 0 3 2 0 2 1 3 0 3 2 1 3 4 4

A836 12 4 1 10 7 2 10 3 1 1 0 3 1 7 7 2 1 12 5

B876 3 0 0 1 1 1 1 0 0 1 0 2 0 1 2 0 0 2 1

B874 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

C1025 3 1 0 1 3 0 0 2 1 0 1 1 0 2 2 0 0 4 0

Other C/U Class 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Total 18 8 2 12 15 3 11 6 2 4 2 9 1 11 11 3 4 19 9


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12.5.22 There is no obvious pattern in relation to the 28 injury accidents recorded, with the majority of accidents located on the main A-Class routes and only 2 accidents recorded involving HGV’s, none of which were fatal.

Future Baseline

12.5.23 The main construction phases of the Proposed Development (Phases 1-5 as set out in Chapter 2: Description of Development) would be completed by 2018 although following this additional activities (Phase 6) will extent the programme through to final completion in 2019. For the purpose of the traffic assessment, a 22 month main construction period has been assumed to cover Phases 1-5. Any lengthening in the programme would have a reduced impact on the surrounding road network in respect to peak period trip generation.

12.5.24 To assess the likely effects during the construction phase, base year traffic flows were determined by applying the National Road Traffic Forecast (NRTF) high growth factors to the surveyed traffic flows. Applying high NRTF growth factors provides a robust assessment as they represent higher than average growth. The NRTF high growth factor is 1.0670.

12.5.25 2018 Base traffic conditions are indicated in Table 12.8.

Table 12.8: 2018 Base Traffic Flows (Weekday Average Two Way Flows)


Total

A836 east of C1025 12 Hours 3925 19 3965

24 Hours 4781 19 4815

A836 east of B876 12 Hours 1802 9 1823

24 Hours 2146 9 2168

C1025 south of A836 12 Hours 2104 11 2118

24 Hours 2827 17 2847

B876 south of A836 12 Hours 1652 15 1681

24 Hours 2001 17 2029

B874 east of A9 12 Hours 195 6 203

24 Hours 232 6 240

C1033 west of U1633 12 Hours 77 3 82

24 Hours 104 3 108

U1727 north of B874 12 Hours 115 2 117

24 Hours 142 2 145


12.6.1 Potential traffic and transport impacts associated with the Proposed Development would be related to traffic movements during the construction period. During construction, vehicles would access the site transporting construction staff,


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construction materials (aggregates, cement, steel bar etc.), plant items and tower components. The decommissioning phase would involve fewer trips on the network than the construction phase as elements of infrastructure such as the foundations and access tracks would be left in place. As described in Section 12.4 of this chapter potential impacts during the operational phase would be extremely unlikely due to the low levels of movements and have therefore not be considered further.

12.6.2 The perception of changes in traffic is dependent upon a wide range of factors including its volume, speeds, function and its composition (e.g. percentage of heavy goods vehicles). Therefore, the assessment of the environmental effects of traffic requires a number of stages, namely:

determination of existing and forecast traffic levels and characteristics;

determining the time period suitable for assessment;

determining the year of assessment; and

identifying the geographical boundaries of assessment.

12.6.3 In accordance with the IEMA Guidelines (1993), the assessment was undertaken on road links where:

Traffic flows are predicted to increase by more than 30% (or where the number of heavy goods vehicles is predicted to increase by more than 30%); and

Traffic flows are predicted to increase by 10% or more in any other specifically sensitive areas.

Potential Construction Impacts

12.6.4 The assessment presents the potential effects of construction traffic, and identifies those which are likely to be significant.

12.6.5 The effects recommended to be potentially important in the EIA guidelines, when assessing the traffic effects from an individual development, listed below, have been considered:

Severance – severance is the perceived division that can occur within a community when it becomes separated by a major traffic artery resulting from the difficulty of crossing a heavily trafficked road or a physical barrier created by the road itself;

Driver delay – these delays are only likely to be significant when the traffic on the network surrounding the development is already at, or close to, the capacity of the system;

Pedestrian delay – the delay to pedestrians, as with driver delay, is likely only at , or close to the capacity of the system;

Pedestrian amenity – the guidelines for the environmental assessment of road traffic suggest that a tentative threshold for judging the significance of changes in pedestrian amenity would be where traffic flow (or its lorry component) is halved or doubled;

Perception of Safety – there are no commonly agreed thresholds for estimating levels of danger, or fear and intimidation, from known traffic and physical conditions;

Accidents and safety – professional judgement will be used to assess the implications of local circumstances, or factors which elevate or lessen risks of accidents; and


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Dust and dirt – there are no simple formulas to predict the levels of dust and dirt which might arise although an estimation of the likely construction volumes will be useful background to provide an informed decision.

12.7 Mitigation


12.7.1 The primary mitigation measure to help minimise the effects of the construction traffic was careful consideration of the road network to identify a preferred route to and from the proposed development for construction traffic. This considered physical characteristics of the road network and the number and location of potentially sensitive receptors along the various routes.

12.7.2 The proposed access strategy has been designed to minimise the amount of new permanent track that requires construction. This has been achieved through the use of existing access junctions and upgrading sections of existing track where possible.


12.7.3 The access routes for construction traffic from the A9/A836 to the proposed access track network will be finalised following the appointment of the Principal Contractor. Figure 12.3: Potential Access Routes illustrates the likely access routes to each section of the Proposed Development from the A9/A836.

12.7.4 The local road network in the vicinity of the proposed access track network generally consists of 2.5 m - 3 m wide single track road with passing places. It is likely that upgrades to the local road network will be required in specific areas subject to confirmation of the final access routes and these will be agreed with THC prior to construction. Upgrades are likely to take the form of localised carriageway widening, carriageway strengthening and additional passing places to ensure the safe movement of construction traffic.

12.7.5 During the construction period the Applicant would maintain a website containing the latest information relating to traffic movements associated with vehicles accessing the site. This will be agreed with THC roads officers.

12.7.6 The following additional mitigation measures are will be implemented during the construction phase:

All materials delivery lorries (dry materials) would be sheeted to reduce dust and stop spillage on public roads; and

Specific training and disciplinary measures would be established to ensure the highest standards are maintained to prevent construction vehicles from carrying mud and debris onto the carriageway, wheel wash facilities will be established at the site entrances.

12.7.7 A Construction Environmental Management Plan (CEMD) would set out measures to be put in place to reduce the impact of noise, dust and excessive speed. The principles of the CEMD are set out in Chapter 2: Description of the Development and Technical Appendix 2.1.

12.7.8 Vehicles will be fitted with identification numbers to allow the public to identify any vehicles that may be speeding or causing specific issues and drivers will be


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required to pass through sensitive areas at low speed. This will form part of the proposed Traffic Management Plan.

12.7.9 In order to mitigate against pedestrian amenity impacts, construction traffic will be discouraged from travelling on the A836 and B876 through Thurso and Castletown during peak school hours. Construction traffic accessing the western half of the site will approach from the A9 and U2188 to avoid any impact on the northern section of the C1025.

12.7.10 A detailed Traffic Management Plan (TMP) will set out measures to help reduce delays encountered with abnormal load transport for drivers. This would include measures such as timing deliveries during off-peak periods. Other measures such as advance warning signs will help drivers consider non-impacted routes as alternatives for their journeys.

12.7.11 A road sweeper will also be deployed when required, on the various sections of the unclassified road network adjacent to the site access points to ensure that the road network is kept clean and free running.

12.7.12 Wherever possible, contractors will be encouraged through the CEMD, to use low emissions vehicles so mitigating against air pollution.


12.7.13 Site roads would be well maintained and monitored to limit any material brought onto public roads by maintenance traffic travelling to and from site during the operational phase.

12.8 Assessment of Residual Impact


12.8.1 This section considers the level of sensitivity of the local road network, to the increase in vehicle movements associated with the construction phase, and to the off-site route improvements required for the construction traffic. It then considers the likely magnitude of impacts assuming the mitigation proposed above is implemented in full. These are then combined to arrive at a determination of whether or not a significant effect in EIA terms is anticipated.

12.8.2 During the 27 month construction phase, it is anticipated the following traffic would require access to the site:

staff transport, either cars or staff minibuses;

construction plant such as excavators, dump trucks cranes and, deliveries of machinery and scaffolding; and

construction materials such as aggregate, concrete and the steel tower components.

12.8.3 Due to the nature of materials and plant required on-site, the majority of vehicles utilised would be HGV (OGV 1 + OGV 2). The construction phase is estimated to be 27 months duration, with construction deliveries phased in accordance with Appendix 12.1.

12.8.4 As discussed in Chapter 2: Description of Development it is anticipated that a single main construction depot will be required and some plant, materials and the


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work crew will be transported to the work site areas from this location. The location of the main construction depot will be confirmed by the Principal Contractor and as such no assessment has been undertaken of traffic generated by the construction depot.

12.8.5 Of the construction, operational and decommissioning phases, the greatest traffic volumes are associated with the construction phase. This assessment has therefore focused on the construction phase as the worst case transport scenario. It is noted however that the construction impacts are temporary in nature.

12.8.6 The assessment is based upon construction traffic estimates for the OHL and underground cable sections of the route provided by the Applicant4. Tables 2.4 and 2.5 of Chapter 2: Description of Development estimate the total anticipated two way traffic movements, with the movements for each phase of construction summarised below in Table 12.9. The predicted movements over the 22 month construction programme are provided in full in Appendix 12.1.

Table 12.9: Summary of Predicted Construction Traffic Generation

Phase Car & Lights OGV 1 OGV 2 Total

Overhead Line

Phase 1: Distribution network alterations – NOT part of Section 37 application

Phase 2: Enabling Works 60 210 8115 8385

Phase 3: Installation of Foundations

58 408

122 588

Phase 4 : Installation of Towers

65 234

117 416

Phase 5 : Conductor Stringing

64 174

126 364

Phase 6 : OHL Commissioning

30 0 0 30

Phase 7 : Reinstatement 0 55 0 55

Underground Cable

Phase 1 : Enabling Works (including access track construction)

1647 108 252 2007

Phase 2 : Construction 9283 2868 16315 28466

12.8.7 The indicative construction phasing detailed in Table 2.2 of Chapter 2 Description of Development was used to convert the total movements for each trip type to average monthly traffic flows. To enable comparison of the estimated 2018 baseline traffic flows with total volumes including predicted construction traffic, the monthly data was converted to average daily flows for each month and the peak period for construction traffic determined.

4 Traffic estimates and the associated programme have been provided to WYG by SHET during e-mail correspondence and

telephone conversations between the SHET project manager and the traffic consultants of WYG.


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12.8.8 The maximum traffic impact associated with construction of the Proposed Development is predicted to occur in months 2 and 3 of the programme. During this month an average of 158 vehicle movements are predicted per standard 8 hour working day.

Development Traffic Distribution

12.8.9 It was assumed that all construction traffic associated with the site will approach the site by way of the A9 / A836 / B874 and B876.

12.8.10 It is assumed that all materials and plant will originate from the south along the A9 with construction traffic access to the various sections of the Proposed Development likely to be distributed as follows:

A9 / B874 / U2314 – 20%;

A9 / U2188 – 20%;

A9 / B876 – 50%; and

A9 / A836 / U1633 – 10%.

12.8.11 Construction traffic will distribute from the above routes onto the wider C/U Class minor road network providing access to the individual tower locations.

Traffic Impact

12.8.12 The 2018 future year traffic data was combined with the peak daily construction traffic flows to estimate the total trips on the study network during the peak of the construction phase. These were then distributed across the road network.

12.8.13 Table 12.10 illustrates the peak weekday 2018 construction traffic flow; Table 12.11, the 2018 Base plus peak construction traffic (Total) flows; and Table 12.12, the percentage increase in 2018 Total traffic over 2018 Base traffic.

Table 12.10: Weekday Construction Traffic (Weekday Average Two Way Flows)


Total

A836 east of C1025 12 Hours 16 79 95

24 Hours 16 79 95

A836 east of B876 12 Hours 3 13 16

24 Hours 3 13 16

C1025 south of A836 12 Hours 0 0 0

24 Hours 0 0 0

B876 south of A836 12 Hours 12 66 78

24 Hours 12 66 78

B874 east of A9 12 Hours 5 26 31

24 Hours 5 26 31

C1033 west of U1633 12 Hours 3 13 16

24 Hours 3 13 16


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Table 12.10: Weekday Construction Traffic (Weekday Average Two Way Flows)


Total

U1727 north of B874 12 Hours 5 26 31

24 Hours 5 26 31

Table 12.11: 2018 Total Weekday Flows (Weekday Average Two Way Flows)


Total

A836 east of C1025 12 Hours 3941 98 4060

24 Hours 4797 98 4910

A836 east of B876 12 Hours 1805 22 1839

24 Hours 2149 22 2184

C1025 south of A836 12 Hours 2104 11 2118

24 Hours 2827 17 2847

B876 south of A836 12 Hours 1664 81 1759

24 Hours 2013 83 2107

B874 east of A9 12 Hours 200 32 234

24 Hours 237 32 271

C1033 west of U1633 12 Hours 80 16 98

24 Hours 107 16 124

U1727 north of B874 12 Hours 120 28 148

24 Hours 147 28 176


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Table 12.12: Percentage Impact Increase 2018 Base v 2018 Total (Weekday Average Two Way Flows)

Survey Location Time Period Cars & Lights HGV Total

A836 east of C1025 12 Hours 0.41% 415.79% 2.40%

24 Hours 0.33% 415.79% 1.97%

A836 east of B876 12 Hours 0.17% 144.44% 0.88%

24 Hours 0.14% 144.44% 0.74%

C1025 south of A836 12 Hours 0% 0% 0%

24 Hours 0% 0% 0%

B876 south of A836 12 Hours 0.73% 440.00% 4.64%

24 Hours 0.60% 388.24% 3.84%

B874 east of A9 12 Hours 2.56% 433.33% 15.27%

24 Hours 2.16% 433.33% 12.92%

C1033 west of U1633 12 Hours 3.90% 433.33% 19.51%

24 Hours 2.88% 433.33% 14.81%

U1727 north of B874 12 Hours 4.35% 1300.00% 26.50%

24 Hours 4.35% 1300.00% 21.38%

Link Capacity profile

12.8.14 The average link capacities for the various links within the study area have been estimated using the NESA Manual, Chapter 3. The theoretical capacities are detailed below:

A836 – around 21,600 vehicles per 12 hours;

B876 – around 19,200 vehicles per 12 hours;

B874 – around 3,360 vehicles per 12 hours;

C1025 – around 19,200 vehicles per 12 hours;

C1033 – around 3,360 vehicles per 12 hours; and

U1727 – around 3,360 vehicles per 12 hours.


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12.8.15 A comparison of the theoretical capacity versus the estimated ‘2018 Future Year Traffic Base Traffic Flow + Construction Phase Trips’ 12-hour flows for the links in the network is illustrated in Graph 12.1.

Graph 12.1 Theoretical Capacity Profile

12.8.16 The impact review was undertaken for weekday conditions and the results indicate that the greatest impact of construction traffic will be on the minor road network represented in the assessment by the B874, C1033 and U1727. However, this reflects the low number of trips and particular HGV trips on these sections of the road network. The comparison of development traffic flows with theoretical link capacities indicates that there is significant spare capacity on the local road network and no link capacity issues associated with the construction traffic would be anticipated.

12.8.17 With reference to the IEMA guidelines, total traffic flows are not predicted to increase by more than 30% on any link although HGV levels will increase by more than 30% on all sections of the route subject to construction traffic. The critical links are therefore considered to be the sections of the route within settlements with pedestrian facilities due to the uplift in HGV movements. The maximum number of additional HGV movements per day is 88 on the A836 and B876. This is considered low when spread over the course of a day.

12.8.18 A route evaluation has been carried out for the minor road network against the key environmental criteria identified by the IEMA guidelines.

12.8.19 The impacts of statistical significance are restricted to the local road network. No impacts on the trunk road network are considered significant and therefore do not warrant further assessment as the percentage increase in total traffic is less than 30% as outlined in Table 12.12.


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Traffic & Transport


12.8.20 The road network in the vicinity of the Proposed Development is generally made up of rural B/C/U-class single track roads that are not designed for frequent use by HGVs. Loads will pass through the settlements of Thurso and Castletown along with numerous scattered settlements located close to the minor road network.

Impact Magnitude and Identification of Significant Effects

SEVERANCE / PERCEPTION OF SAFETY

12.8.21 Severance and perception of safety along the route for pedestrians would only affect those links within the study area that contain settlements with pedestrian facilities (A836/B876) are likely to be impacted. The increase in traffic flow affecting receptors within the settlements of Thurso and Castletown are summarised in Table 12.12. Based on the two-way average daily Total traffic flows and change in total traffic flows on the A836/B876, the perception of safety impact is estimated to be negligible at the receptors along the access route due to the low volumes of overall traffic.

DRIVER / PEDESTRIAN DELAY

12.8.22 There is the potential for limited driver delay during the peak construction phases due to the limited passing opportunities along the single track sections of road network although localised improvements will be introduced where required to accommodate the safe movement of construction traffic and reduce impacts on general traffic.

12.8.23 There is significant spare capacity along the links assessed and the driver delay impact is therefore estimated to be negligible at the receptors along the route.

12.8.24 Due to the low volumes of overall traffic there is unlikely to be any pedestrian delay on the links within the study area that contain settlements with pedestrian facilities. The pedestrian delay impact is therefore estimated to be negligible at the receptors along the route.

PEDESTRIAN AMENITY

12.8.25 The magnitude of the impact on pedestrian amenity has been considered in terms of the threshold described in the MEA. Therefore based on the estimated two-way percentage increases in HGV traffic summarised in Table 12.12 the threshold for changes to pedestrian amenity have been reached on all links other than the C1025.

12.8.26 There are currently no pedestrian facilities along the rural sections of the access routes and limited pedestrian demand. Pedestrian facilities are available within Thurso and Castletown although through the CEMD, HGV traffic will be discouraged from travelling through Thurso and Castletown during peak school hours.

12.8.27 With mitigation measures in place through the CEMD the pedestrian amenity impact is likely to be moderate at the receptors along the route where settlements with pedestrian facilities are present.


Gills Bay 132 kV


ACCIDENTS AND SAFETY

12.8.28 Accident data was analysed along the C1025/C1033 and U1727 with the overall number of accidents considered to be low.

12.8.29 Due to the width of the route it will be necessary for construction vehicles to maintain a low speed along the minor road network. Construction working will also be limited to daytime working with the aim of further reducing the accident risk. With mitigation measures in place the accidents and safety impact is therefore estimated to be negligible at the receptors along the route.

DUST AND DIRT

12.8.30 There are no specific guidelines to determine magnitude of impact of dust and dirt although its impact is likely to be limited to the immediate vicinity of the site access junctions, with mitigation proposed to ensure that the impact is negligible.


12.8.31 No residual operational effects are likely due to the limited vehicles access associated with the site during the operational phase.


12.9.1 THC and Transport Scotland did not request that any other schemes were taken into account as part of the access, traffic and transport impact assessment. No cumulative impact assessment was therefore undertaken for this Chapter.

12.9.2 A number of renewable energy schemes are located in the vicinity of the study area. Of these only Stroupster wind farm is consented with the remainder of sites either under appeal or at the pre-application stage. In addition there is the committed Dounreay-Mybster connection and Thurso south substations projects located to the west of the proposed development.

12.9.3 It is extremely unlikely that all adjacent schemes peak movements would occur at the same time due to differing grid connection dates, progress through the planning system and the limited capacity of surrounding quarries to service such a large number of sites simultaneously in terms of construction materials.

12.9.4 Any remaining impact of construction traffic is largely accounted for by using NRTF high growth and as such no further assessment was undertaken.

12.10 Summary

12.10.1 This chapter has assessed the likely significance of effects of the traffic associated with the Proposed Development during the construction phase. Based on existing traffic data, the estimated volume of construction traffic, the methodology outlined, the implementation of mitigation measures such as an appropriate traffic management plan and suitable liaison with the relevant authorities, an assessment of the residual effect has been made. The overall residual traffic and transport effects are temporary and have been assessed as having low significance.


LT000022 12-23 Chapter 12:

Traffic & Transport

Table 12.13: Summary of Potential Impacts of the proposed development, mitigation and Residual Impacts




Construction

Severance / Perception of Safety

Measures such as numbering of all construction vehicles would be instigated and strict adherence to speed limits would be required by all vehicles. Drivers would be fully briefed to ensure that they are aware of pedestrian and cycle crossings along the route.

Traffic Management Plan (TMP)

Negligible

Driver / Pedestrian Delay

A community liaison group would also be set up to facilitate communication with the local community.

Localised upgrades to the local road network will provide additional passing opportunities where these are deemed necessary.

Community Liaison Group

Negligible

Pedestrian Amenity Drivers will be required to pass through sensitive areas at low speed and vehicles will be fitted with identification numbers.

Drivers will be discouraged from travelling through settlements during peak school hours.

TMP Moderate

Accidents and Safety Construction traffic will only travel on the local road network during daylight hours. Drivers will be required to travel along single track road at low speed.

TMP Negligible

Dust and Dirt A wheel wash facility would be provided onsite and all lories

CEMD Negligible


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Table 12.13: Summary of Potential Impacts of the proposed development, mitigation and Residual Impacts




carrying bulk materials would be sheeted in order to prevent dust and dirt.

Operation

None


LT000022 13-1 Chapter 13:

Noise

13 NOISE

13.1 Introduction

13.1.1 This chapter considers the potential impacts on noise sensitive receptors from the construction and operation of the Proposed Development. The specific objectives of the assessment are outlined below:

to identify noise sensitive receptors in the vicinity of the Proposed Development;

to quantify the potential operational noise generated by the OHL - especially when the surface of conductors becomes wet during rainfall;

to describe the likely potential impacts on noise sensitive receptors as a result of operation of the Proposed Development;

to describe mitigation measures that have been committed to in order to avoid or reduce impacts, including construction impacts; and

to assess the significance of residual impacts that are likely to remain following implementation of mitigation measures.

13.1.2 This chapter considers the OHL portion of the Proposed Development only, as potential operational noise arises only when the surface of conductors becomes wet during rainfall. Therefore noise effects from the underground cabling have been scoped out of the EIA.

13.1.3 This chapter and the impact assessment described within have been prepared by Lukasz Jakielaszek MIOA of Ramboll Environ UK Limited (Ramboll Environ).



13.2.1 The overarching legislation instruments in the Scottish planning system are Scottish Planning Policy1 (SPP), which deals with nationally important land use planning matters, and the National Planning Framework2 (NPF), which outlines Scottish Government’s policy for long term spatial development. These documents promote sustainable growth and protect the environment.

13.2.2 Information on technical planning matters is provided in Planning Advice Notes (PANs). In relation to noise, Planning Advice Note (PAN) 1/2011: Planning and Noise3 gives advice on the role of the planning system in helping to prevent and limit the adverse effects. The PAN promotes the principles of good acoustic design and a sensitive approach to the location of new developments, such that new potentially noisy developments do not unreasonably affect quality of life and that new developments continue to support sustainable economic growth.

13.2.3 PAN 1/2011 identifies a need of Noise Impact Assessments (NIA) in the planning process. The purpose of NIA is to demonstrate whether any significant adverse

1 Scottish Planning Policy, The Scottish Government, Edinburgh, 2014 2 Scotland’s Third National Planning Framework, Edinburgh, 2014 3 Planning Advice Note 1/2011, Planning and Noise, The Scottish Government, March 2011


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Chapter 13: Noise 13-2 LT000022

noise impacts are likely to occur and is done to identify what effective measures could reduce, control and mitigate significant noise impacts where necessary.

13.2.4 The National Policy Statement (NPS) for Electricity Networks Infrastructure (EN-5) may be a relevant consideration in planning decisions in Scotland, as energy policy is generally a reserved matter to UK Ministers. EN-5 also provides a specific method for assessment of noise from high voltage OHLs. It is recommended, that the assessment method developed by National Grid and presented in their Technical Report TR(T)944 is used in order to determine the community response to noise levels exceeding the normal background conditions.


13.3.1 Table 13.1 below summarises the issues identified during the consultation process that are of relevance to the noise assessment.



Transport Scotland Potential trunk road related environmental impacts such as noise, air quality, safety etc. should be assessed where IEMA Guidelines for further assessment are breached.

The transport assessment in Chapter 12 indicates IEMA Guidelines for further assessment are not breached.

Noise and vibration: Operational and construction traffic noise should be assessed by considering the increase in traffic flows and following the principles of CRTN, DMRB Vol 11 and PAN56. The ES should consider potential impacts to any identified trunk road receptors, in terms of predicted noise levels from construction traffic.

Construction noise including noise from construction traffic will be short term and intermittent and can be controlled through the implementation of appropriate requirements within the CEMD which would include working hours as specified by ECDU/THC.

The commitments which are required within the CEMD in order to control construction traffic are set out in Chapter 14: Schedule of Mitigation.

Operational traffic noise will be minimal (line maintenance only) and subject to requirements within the CEMD relating to working hours and management controls. Therefore this has also been scoped out of the assessment.

4 Technical Report TR(T)94, A Method for Assessing the Community Response to Overhead Line Noise, Issue 1, National Grid,

October 1993


LT000022 13-3 Chapter 13:

Noise



Study Area

13.4.1 The study area was defined as 1.5 km from the Limit of Deviation (LOD) of the Overhead Line section of the Proposed Development. This is shown in Figures 13.1-13.4.

Noise sensitive receptors

13.4.2 Noise sensitive receptors (NSRs) were identified as all residential properties within the study area. The nearest NSRs are located at a minimum distance of 100 m from the LOD, with an exception of a single NSR, which is 89 m from the LOD. The location of the NSRs is shown in Figures 13.1 - 13.4.


13.4.3 OHL noise is generated by a phenomenon called “corona discharge”, which occurs mainly during rain. The intensity of generated noise is proportional to the amount of rainfall, however background noise levels without the OHL also increases with rainfall. TR(T)94 provides a method for estimating the background noise level as a function of rainfall rate, which can be added to the prevailing background noise level in dry weather.

13.4.4 Without the specific background noise measurements taken at the nearest noise sensitive receptors, the rain noise level as defined in TR(T)94 is taken to solely represent the baseline conditions without the Proposed Development. It is considered that such an approach will constitute a worst-case assessment. All identified noise sensitive receptors were classified as “R-1” by reference to TR(T)94. These receptors correspond to those located on bare ground, with cover of relatively small-leafed vegetation, such as grass lawn or meadow, or within a field of small-leafed plants.

13.4.5 The predicted noise levels for the Proposed Development have been derived from the noise emissions predicted for the Spittal to Mybster 132 kV line in Caithness. These were presented in the Spittal – Mybster design study report5 and used in the ES submitted to the Scottish Government in support of the application under Section 37 of the Electricity Act 1989 and deemed planning permission under S57(2) of the Town And Country Planning (Scotland) Act 1997 to construct a 275kv OHL from Dounreay to Spittal and a 132kv OHL from Spittal to Mybster6.

13.4.6 The average rainfall rate in the area is assumed to be the same as presented in the Spittal to Mybster study.


13.4.7 The significance criteria of rain induced OHL audible noise were established by reference to the estimated community response to noise levels exceeding normal

5 Dounreay– Spittal/Thurso South and Spittal – Mybster, Proposed 275 kV and 132kV Overhead Line Routes, Phase 2 Design,

Gate 2 Report, Part 1, Scottish and Southern Energy Power Distribution, May 2012 6 Application For Consent Under S37 Of The Electricity Act 1989 And Deemed Planning Permission Under S57(2) Of The Town And Country Planning (Scotland) Act 1997 To Construct A 275kv Transmission Line From Dounreay To Spittal And A 132kv Transmission Line From Spittal To Mybster In The Highland Council Area - https://www.ssepd.co.uk/DounreayMybster/


Gills Bay 132 kV


background as presented in TR(T)94. The adopted significance criteria are described in Table 13.2.

Table 13.2: Adopted significance criteria for operational noise effects

Exceedance of line noise level above normal background

Category of community response

Description of community response

Impact significance

Less than 3dB Negligible No observed reaction Negligible

3dB to 5dB Little Sporadic complaints Minor

6dB to 10dB Medium Widespread complaints

Moderate

Over 10dB Strong and very strong

Threats of community action

Major

13.4.8 Any potential operational noise effects would be classified as adverse, direct and permanent.

Issues Scoped out of Assessment

13.4.9 As indicated in Section 13.1, the assessment considers the OHL portion of the Proposed Development only, as potential operational noise arises only when the surface of conductors becomes wet during rainfall. There are no predicted noise effects from the underground cabling, therefore, that was scoped out of the EIA.

13.4.10 Potential construction noise impacts were also scoped out of the EIA. These will be minimised through the implementation of management controls, to be contained in the Construction Environmental Management Document (CEMD). These measures, including working hours, are outlined in Chapter 14: Schedule of Mitigation.

13.4.11 Construction noise including noise from construction traffic will be short term and intermittent and can be controlled through the implementation of these appropriate requirements within the CEMD.


13.5.1 The baseline conditions at all of the NSRs considered in the assessment are assumed to be characterised by rain as a function of its intensity rate, expressed in terms of rainfall rate and are presented in Figure 13.. This relationship originates from TR(T)94 and is considered representative of a rural location with essentially bare, greenfield ground conditions without trees.

13.5.2 Background noise levels would normally be determined as a sum of the background level in dry weather conditions and rain as a function of its intensity. No specific background noise level measurements were taken in the study area on the basis that the area is rural, with few existing noise sources, and will approximate to levels characteristic of “rain noise”. Such an approach is considered appropriate as the OHL noise mainly occurs in rain. It will also represent a worst-case as existing sources of noise would not be taken into account, and potential exceedance of OHL noise would be at its greatest.


LT000022 13-5 Chapter 13:

Noise

13.5.3 The relationship of noise level with rainfall rate is presented in Figure 13.5. It is noted that at the trace rain of 0.01 mm/h, the background noise levels are in the region of 20 dB, which is not uncommon in remote rural locations.

Figure 13.5 Assumed background noise levels resulting from rain

Current Baseline

13.5.4 The mean rainfall rate noted for Caithness and presented in the Design Report (May 20127) is 0.38 mm/h. At such a rainfall rate, the background noise level is estimated to be 35 dB LAeq.

Future Baseline

13.5.5 The established baseline noise level is considered representative of the current and future levels, as general background in dry weather is not taken into account.


13.6.1 As indicated in paragraph 13.4.5, the audible noise from the Proposed Development has been sourced from a design study presented for the Spittal to Mybster OHL. The study predicted audible noise under wet weather conditions using a number of semi-empirical methods. These predictions were made under rain conditions above 1 mm/h rainfall rate, and for a propagation distance up to 50 m from the OHL. Emission values are presented in Table 13. and are assumed to relate to individual sub-conductors within the OHL. Audible noise is also calculated at a distance of 100 m.

7 Dounreay– Spittal/Thurso South and Spittal – Mybster, Proposed 275 kV and 132kV Overhead Line Routes, Phase 2 Design, Gate 2 Report, Part 1, Scottish and Southern Energy Power Distribution, May 2012

15

20

25

30

35

40

45

50

55

60

65

0.01 0.1 1 10 100

No

ise

leve

l d

B(A

)

rainfall rate [mm/h]


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Table 13.3 Predicted OHL noise level from single conductor under wet weather

Prediction method Audible noise level dB LAeq

50 m 100 m

Ente Nazionale per L’Energia Elettrica (ENEL)

23 20

Electricité de France (EdF) 23 20

Bonneville Power Administration (BPA) 13 10

High Voltage Transmission Research Center (HVTRC)

9 6

13.6.2 For the purpose of this assessment, audible noise predicted using ENEL and EdF model is used.

13.6.3 The audible noise with rainfall rate up to 1 mm/h is characterised by a broadband “crackle” which does not contain pure tones. The audible noise with rainfall rate above 1 mm/h can also include a 100 Hz “hum”. According to TR(T)94 and consistent with BS 4142:20148, a tonal correction would be added to noise emission with rainfall above 1 mm/h, however, since the mean assumed rainfall for the study area is 0.38 mm/h, no tonal correction has been added in this assessment.

13.6.4 The total audible noise from the OHL is calculated as a sum of the individual emission from six sub conductors. Consequently, total audible noise from the OHL is calculated as:

Audible noise from 6 conductors at 100 m = 20 dB + 10*log10(6) = 28 dB.

13.6.5 In order to determine the exceedance of audible OHL noise over the 35 dBLAeq background noise level at the mean rainfall rate of 0.38 mm/h, the predicted OHL noise is added to the background noise with rain.

13.6.6 It needs to be noted that at other rain conditions, different than the assumed mean rainfall rate, the OHL may potentially produce an audible noise higher than at the prevailing, mean rain rate, however such circumstances are not considered further as they will be uncommon.

13.6.7 The assessment of audible noise is carried out at distances including 89 m and 100 m, which are representative of the nearest residential properties. The position of the OHL within the LOD has been assumed to be at the closest possible point to the NSRs, which is a worst case assumption. The assessment of impacts is presented in Table 13.4.

8 BS 4142:2014,


LT000022 13-7 Chapter 13:

Noise

Table 13.4 Assessment of OHL operational noise

Distance from NSR

to LOD

Background noise level with rain

dB(A)

OHL audible

noise level dB(A)

Total noise level of OHL and background

dB(A)

Exceedance of total noise over background dB

Potential effect

89 m 35 28 36 1 Negligible




13.6.8 The calculated OHL audible noise does not include the tonality correction as the mean rainfall rate for the assessment area is taken as 0.38 mm/h, and the hum inception rainfall rate is at 1 mm/h.

13.6.9 It is noted that those NSRs located 100 m or less from the LOD being applied to the OHL may experience a 1dB noise level increase as a result of the Proposed Development. Those located greater than 100 m from the LOD will experience no perceptible increase in noise levels.

13.7 Mitigation

13.7.1 Mitigation for the operational noise of OHL has been incorporated during the design stage, whereby the alignment of the OHL has been defined to be in all but one case a minimum of 100 m from the nearest NSR.

13.7.2 No additional mitigation is proposed for the operational phase of the OHL.


13.8.1 From Table 13.4 it is evident that the Proposed Development would give rise to a negligible noise impact at all NSRs.

13.9 Cumulative Impacts

13.9.1 The LOD of the Proposed Development is within 1 km of two wind farm projects, which are both at the pre-planning stage with The Highland Council. It is considered that other proposed wind farm projects greater than 1km from the Proposed Development would not materially contribute to the noise environment at NSR considered for the OHL assessment. The identified wind turbine projects are developments at Coghill – 3 turbines 0.5 km from the Proposed Development, and development at Stemster, 4 turbines approximately 1 km from the Proposed Development.

13.9.2 Direct evaluation of wind turbine cumulative noise effects with the Proposed Development is not feasible, as the two development types are subject to different assessment criteria.

13.9.3 Wind turbine noise is generally assessed with a criterion of 5 dB above the pre-existing background noise level and as a function of wind speed, whereby background noise level also increases with wind; or is assessed against a lower


Gills Bay 132 kV


limit of 35 dB LAeq. Conversely, OHL audible noise needs to be 10 dB below the background noise level in order not to increase the background noise.

13.9.4 Nevertheless, the assessment of potential effects is carried out by reference to criteria adopted in this chapter. Each of the developments, either wind turbine or OHL, will contribute most to each other’s noise emissions in a situation when both result in equal specific noise levels at a receptor location. Wind turbine developments will therefore contribute most to OHL noise when both result in 28 dB LAeq, the highest predicted noise level from the OHL.

13.9.5 Therefore, under the condition whereby the OHL and the wind turbines each result in a noise level of 28 dBLAeq at the common NSRs, the combined noise effect from both would be 31 dBLAeq. Such a calculation is based on the principle that doubling the acoustic energy equates to an increase of 3 dB in sound level. The cumulative noise level of 31 dBLAeq would increase the baseline noise level of 35 dBLAeq by 1 dB. Consequently, the Proposed Development is assessed to have a negligible noise impact when assessed cumulatively with wind turbine developments.


13.10.1 The assessment of operational noise effects resulting from the OHL has been undertaken by reference to the National Policy Statement for Electricity Networks Infrastructure. The policy recommends the methodology and assessment procedure as described in TR(T)94, which recognises that audible noise from an OHL occurs during rain, taking account that background noise levels also increase with rain.

13.10.2 It has been established that baseline noise conditions were dominated by rain noise, and were based on the mean rainfall rate relevant for the study area, as presented in a design study for a nearby development.

13.10.3 Potential noise effects at all receptors nearest to the Proposed Development were assessed as negligible, and no therefore mitigation options were considered. A summary of the impacts is shown Table 13.5.

Table 13.5: Summary of Potential Operational Impacts of the Proposed Development, Mitigation and Residual Impacts of the OHL



Negligible None N/A Negligible


LT000022 14-1 Chapter 14:

Schedule of Mitigation

14 SCHEDULE OF MITIGATION

14.1 Introduction

14.1.1 The purpose of this chapter is to collate the mitigation measures which are proposed in each of the technical chapters of this ES into a single schedule, which is presented in Table 14.1 below. Measures to mitigate construction phase and operational phase impacts are included. Measures to mitigate impacts arising apply to all elements of the Proposed Development unless otherwise specified.

14.1.2 Some mitigation measures would serve to avoid impacts, others would reduce or off-set them. Mitigation measures which are designed to enhance beneficial impacts are also included. Environmental impacts and associated mitigation measures are presented in the order in which they appear within this ES.

14.1.3 Mitigation measures which are 'by design', in other words, which have been incorporated into the final design as reflected by the defined LOD for the Proposed Development are not included here as they form part of the Proposed Development described in Chapter 2: Description of Development.


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Chapter 14: Schedule of Mitigation 14-2 LT000022

Table 14.1: Schedule of Mitigation Measures

Mitigation ref

Topic Identified Impact Mitigation/Monitoring Measure Timing of Mitigation Measure

GEN1 General Various. A Construction Environmental Management Document (CEMD) will be prepared by the Applicant defining the methodologies and management measures to be employed in the construction of the Proposed Developments.

The draft CEMD will be submitted for review by SEPA, SNH, Historic Scotland and THC prior to first implementation.

The CEMD will be a live document and will be a condition of contract for the Principal and all sub-Contractors.

Development of a CEMP to address specific issues, in accordance with the CEMD, will be a contractual responsibility of the Principal Contractor (see GEN 3).

Implementation of the CEMD/CEMP will be a contractual responsibility of the Principal Contractor.

The Applicant and their appointed Environmental Clerk of Works (ECoW) (see GEN 2 below) will oversee and audit the implementation of the CEMD and associated CEMPs throughout delivery.

Pre-construction

GEN2 General Various. The Applicant will employ an ECoW to work alongside the Principal Contractor in the implementation of the CEMD/CEMP and delivery of the environmental commitments.

Pre-construction

GEN3 General Various. The CEMD will provide mechanisms for the development of other necessary topic specific plans including:

CEMP. This will be developed for all site works (contractor compounds, access tracks, tower compounds etc.) It will provide for specific protection/management measures for the sensitivities identified in the CEMD.

Species Protection Plan (SpPPs) which l set out specific protection and management measures for sensitive receptors, including otters, reptiles and amphibians. These measures have been agreed between the Applicant and SNH and set out an overarching framework.

Pre-construction


LT000022 14-3 Chapter 14:



Mitigation ref


They will be implemented by all contractors, with oversight of implementation by the Principal Contractor.

LVIA 1 Landscape Resource

Moderate direct and moderate indirect and temporary changes to sweeping moorland and Mixed Agriculture and Settlement Landscape Character Types (LCTs) during construction of access tracks, excavations for the tower foundations and cable route and as a result of construction laydown areas etc.

Where possible micro-positioning of access tracks, towers and cable route to minimise loss of vegetation will be undertaken, all construction activity would be contained within the defined LOD and would be completed in accordance with specific procedures contained within the CEMD/CEMP and with landowner requirements.

Pre-construction/Micro-siting

LVIA2 Landscape Resource

As above. A Tree Protection Plan would be prepared, if necessary, for relevant sections of the LOD in accordance with the CEMD (to specifications for an arboricultural assessment set out in BS 5837:2012 Trees in Relation to Construction) for all trees and hedgerows within the vicinity of works which will remain in place. This will include a Root Protection Zone (RPZ), and may include barrier and ground protection and site monitoring.

Pre-construction


As above. Tower installation would be undertaken in short sections with progressive restoration where possible.

Construction


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Mitigation ref



As above. Cable trench will be progressively restored. Construction


As above. Formation of new and upgrading of existing tracks for use in construction access will be in accordance with specifications provided in the CEMD/CEMP and in consultation with landowners, and in keeping with the character of existing tracks/footpaths e.g. materials and scale.

Construction


As above. Any boulders within the construction footprint would be carefully removed and set aside for subsequent repositioning during reinstatement operations.

Construction/ reinstatement


Limited loss of commercial forestry around Gills Bay.

Removal of trees or hedges would be agreed with The Highland Council and will be in accordance with specific procedures contained in the CEMD/CEMP and with landowner requirements.

Pre-construction


As above. Trees and hedgerows would be reinstated wherever possible on completion of construction in accordance with CEMD/CEMP and with landowner requirements.

Construction


As above. Planting to be maintained by the Applicant for at least 5 years, at which point it would become the responsibility of the landowner. Replacement planting would be undertaken, as necessary within this period to account for any failures.

Construction/ operation


Moderate direct and moderate indirect and permanent changes to sweeping moorland and Mixed Agriculture and Settlement Landscape Character Types

Reinstatement of any temporary access tracks would be completed in accordance with the CEMD/CEMP, in consultation with SEPA and SNH.

Reinstatement


LT000022 14-5 Chapter 14:



Mitigation ref


(LCTs) during operation of the OHL.


As above. Reinstatement of tower compounds and other temporary works associated with construction will be in accordance with the specification provided in the CEMD/CEMP and, where possible, landowner requirements.


As above. The CEMD/CEMP will provide specifications for the management of vegetation and soils to provide for regrowth from the existing seed-bank.


EC 1 Ecology and Nature Conservation

Degradation of peatland habitats/ GWDTE and known mammal locations through construction of access tracks, excavations for the tower foundations and cable route and as a result of construction laydown areas etc.

Access tracks will constructed in accordance with specifications provided in the CEMD/CEMP. Where access tracks cross areas of peat and potential GWDTE habitats design construction would have due regard to key principles set out in the joint SNH/FCS guide to floating roads on peat and adherence to best practice in track construction.

Temporary floated tracks which meet engineering requirements will be provided incorporating sub-track drainage to allow continued movement of groundwater and hydrological connectivity to maintain GWDTE habitats.

The CEMD/CEMP will make provision for subtrack drainage to be installed in the following locations:

where the new stone road crosses areas of marshy grassland habitat considered likely to be of high groundwater dependence at Achingills (Ref to ES Figures 7.3a and 7.4);

for sections of temporary road south of Fryster that cross of marshy grassland habitat considered likely to be areas of high groundwater dependence (Ref to ES Figures 7.3b and 7.4);

for sections of temporary road north of Bowermadden that cross of wet modified bog and marshy grassland habitat considered likely to be areas of high groundwater dependence (Refer to ES Figures 7.3c and 7.4);

Construction


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Mitigation ref


for a section of temporary road north-west of Reaster that crosses of wet modified boy habitat considered likely to be the area of moderate groundwater dependence, (Refer to ES Figures 7.3c and 7.4);

where the new stone road north of Reaster crosses wet modified bog habitat considered likely to be areas of high and moderate groundwater dependence (Refer to ES Figures 7.3d and 7.4);

a stretch of floating road will be constructed to the south of Moss of Greenland (Refer to ES Figures 2.4 and 7.4); and

SLA6, SLA 7 and Hydro 17 apply.

EC2 Ecology and Nature Conservation

As above. Turfs of peatland vegetation would be removed and stored to allow the area to be restored post construction.

Construction


As above. The CEMD/CEMP will provide that, at all locations where temporary construction activities occur within the identified GWDTEs, habitat restoration will be completed following removal of temporary tracks.

Reinstatement


Impact on designated sites – including biological and chemical water quality in the River Thurso SAC/SSSI through accidental releases of silt, fuel or lubricants during the construction phase.

Establishment of buffers around watercourses within LOD (Hydro 12) of the Proposed Development within which construction activities would only occur under protection measures.

In particular, locations next to tributary watercourses of the River Thurso, burns or field drains where pollution or siltation events would have the potential to enter the main river channels would be subject to appropriate preventative measures prior to any works commencing.

Where works are required within 75 m of the River Thurso SAC and its tributaries, detailed method statements and risk assessments will be developed by the main Contractor following SEPA 'Guidelines for Water Pollution Prevention from Civil Engineering Contracts' and 'Special Requirements' and appropriate consultation will be undertaken with SEPA / SNH.

Pre-construction/ construction


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Mitigation ref


Hydro 2 to Hydro 7 apply.


As above. The CEMD/CEMP will specify arrangements for the storage (including bunding requirements) and management for all construction liquids such as fuel or hydraulic fluids.

Construction


As above. The Principal Contractor’s depot(s) will be located at least 75 m away from River Thurso.

Construction


As above. The CEMD/CEMP will specify arrangements for conductor stringing, specifically where the Proposed Development crosses rivers, and will require infrastructure (including scaffolding) to avoid any contact with the river.

Construction


As above. The CEMD/CEMP will provide for the identification and appropriate avoidance of sensitive seasons for ecological receptors where necessary.

Construction


As above. Any excavations which remain uncovered overnight would have mammal ladders deployed to prevent otters and other species from becoming trapped. Additionally all pipes would be capped and chemicals stored securely.

Construction


Impacts on qualifying interests of the River Thurso SAC (Atlantic Salmon).

EC 4 to EC 7 apply.

Hydro 2 to 7 apply.


ORN 1 Ornithology Construction activities have the potential to cause disturbance to SPA designating species.

Where works are proposed between the beginning of October and mid-April the CEMD/CEMP would include method statements and risk assessments setting out the approach to be followed to avoid disturbance around the key goose and swan loafing and foraging area of the fields around Ha’ of Durran. These would be agreed with SNH prior to construction commencement and would be likely to include:



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Disturbance of geese and swans around Ha’ of Durran during construction of OHL.

pre-construction surveys to identify those areas in use by the goose and swan species at the time of the works; and

identification and establishment of buffer zones around the key fields, which would be avoided.

ORN 2 Ornithology Disturbance of geese and swans around the areas east of Loch Heilen: Lochend and Syster during cabling works.

ORN 1 would apply. Pre-construction/ construction

ORN 3 Ornithology Disturbance of geese and swans around the area around Philips Mains during cabling works.

ORN 1 would apply. Pre-construction/ construction

ORN 4 Ornithology Disturbance of breeding birds during construction of OHL and cabling.

Vegetation due to be removed to facilitate construction to accommodate access tracks and at the tower footprints would be removed ahead of the bird breeding season (March-August).

The CEMD/CEMP will include procedures for the timing and methods of vegetation removal to discourage birds from using those areas where construction activity would be occurring.

LVIA 7 and 8 also applies.


ORN 5 Ornithology As above. The CEMD will include measures to deter birds from settling. These measures may include:

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placing iridescent tape across the construction areas prior to construction;

installation of bird deterring devices which produce intermittent loud noises;

walking of the cleared areas by people on a regular basis to prevent birds settling; and

monitoring if any birds are settling to nest on areas close to planned construction activity.

ORN 6 Ornithology As above. The CEMD/CEMP will include provisions if construction activities will occur during the bird breeding season (March-August). This will include a pre-construction survey, to check whether birds are settling to nest within the LODs of the Proposed Development and to check for any Annex 1 or Schedule 1 species such as hen harrier nesting within disturbance distance of the LODs.

ORN 7 Ornithology As above. The CEMD/CEMP would contain procedures for dealing with the protection of any active nest identified during pre-construction surveys. .

ORN 8 Ornithology Collision of geese and swans with the OHL when operational.

The operational OHL present potential collision risk for sensitive bird species (raptors, geese and swans) with conductors and

The need for line marking/bird diverters will be discussed and agreed with SNH with particularly reference to a 5.1 km section of the Proposed Development from Fryster to Wester Olrig.


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earthwires in certain locations.

ORN 9 Ornithology Disturbance of wintering geese and swans during maintenance activities on OHL and cabling.

Where possible, maintenance will be conducted out-with the season when geese and swans could potentially use the fields near the Proposed Development. The CEMD/CEMP will contain methods for undertaking works when birds are present during maintenance works, which could include placing bird deterring machines in the areas to be affected so as to encourage birds to feed/loaf in adjacent fields.

ORN 10 Ornithology Disturbance of breeding birds during maintenance activities on OHL and cabling.

The CEMD/CEMP will contain methods for undertaking works when breeding birds are present during maintenance works, which could include:

cutting of vegetation prior to the breeding period if possible; and

pre-maintenance survey for breeding birds by a suitable trained ornithologist prior to any maintenance or repairs taking place.

Arch 1 Archaeology and Cultural Heritage

Direct Physical Impacts on Known Archaeology Features.

Specifically 2 clearance spreads (36 and 781) and a quarry (43)) affected by the OHL and a clearance spread (4), Grottistoft Moss, Corn drying barn, (Old Corn Mill, Grain mill) (58) and

A programme of archaeological works (written scheme of investigation (WSI) will be included as part of the CEMP, to be observed during construction of the Proposed Development. This will include measures to be taken to protect and preserve any features of archaeological interest in situ and the recording and recovery of archaeological features which cannot be so preserved. .

All works would be conducted by a professional archaeologist (Archaeological Clerk of Works).

1 Numbers refer to assets in Cultural Heritage Chapter – listed in Technical Appendix 9.1 (OHL) and 9.2 (cabling).


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possible kiln (60) affected by the cabling works.


As above. The CEMD/CEMP would include written guidelines for use by all construction contractors, outlining measures to avoid causing unnecessary damage to known heritage assets, including:

arrangements for calling upon retained professional archaeological support in the event that buried archaeological remains of potential archaeological interest (such as building remains, human remains, artefacts etc.) are discovered in areas not subjected to archaeological monitoring; and

legal responsibilities placed upon those who disturb artefacts or human remains.


As above. The CEMD/CEMP would contain methods to exclude known, upstanding heritage assets from working areas, and avoid assets when planning access routes for construction areas to ensure preservation in situ. This would include:

avoidance of upstanding features within c. 50 m of proposed tower locations or within 50m of ground breaking works for the cable by micrositing;

marking-off using hi-visibility fencing placed, wherever possible, a minimum of 10 m from the visible extent of the heritage asset, to prevent avoidable accidental damage occurring to the remains during construction activities in their vicinity; and

routing access tracks through any existing gates or broken (less well preserved) sections of linear features (banks and walls) where possible.


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As above. The CEMD/CEMP would contain methods to investigate and record features that cannot be avoided or protected during construction. This will be to a specification and standard to be agreed in writing with The Highland Council and in consultation with HET. This provision would include the consequent production of written reports on the findings, with post-excavation analyses and publication of the results of the work where appropriate.


Direct Physical Impacts on Unknown Archaeology Features.

A walkover field survey would be carried out, along the route of the LOD at Auchingills, which could not be accessed during the initial walkover survey. This would identify and record the locations/extents of any previously unrecorded upstanding remains in this area and to record the extents and current conditions of known sites that lie within the LOD.


As above. A walkover field survey would be carried out, along the route of the LOD at Tows, Durran following clearance of dense gorse bushes and conifer trees in this area, to record the locations/extents of any previously unrecorded upstanding remains in this area.


Setting (indirect) impacts on setting of Earney Hillock, chambered cairn (439) and Stemster Hill, chambered cairn (486) and 10 Scheduled Monuments (434, 442, 449, 474, 480, 487, 556, 576, 594 and 11239) as a result of the OHL operation.

The CEMD/CEMP would include methods to record setting of these assets prior to construction taking place.


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Hydro 1 Geology, Hydrogeology and Hydrology

Potential Impact of Engineering Works in the Water Environment

Potential for direct physical impacts on sensitive receptors in the water environment, in the event of construction activities, tower placement, cabling works and access tracks, occurring within these features for the LOD of the Proposed Development.

Where engineering works within the water environment are required, a CAR Licence issued by SEPA must be in place prior to works commencing.

The CEMP and CAR application would include the following:

trenching would be at least 0.9 m below the true clean bottom of watercourses or ditches being crossed;

flows in watercourses and ditches would be maintained such that there is no change to hydrology either up or downstream of any works, i.e. no significant flow restriction or increase in conveyance;

no pollution of watercourses or ditches must occur either from sediment during excavation, or chemicals (see also Hydro 5 and 10);

any diversions of watercourses are subject to restoration across the full working width of the watercourses;

flood risk must be minimised by designing flow diversions with sufficient capacity to avoid flood risks; and

works must not commence in advance of proposed methodologies, (and any associated required mitigation), being agreed with SEPA and The Highland Council.


As above. Minimum separation distances between the limit of a work site and the riparian limit of the water course will be defined on a case by case basis within the CEMP. In the event that construction activity is required within these limits detailed method statements and risk assessments will be developed by the Principal Contractor and appropriate consultation will be undertaken with SEPA and SNH.

EC 4 to EC 7 apply.

Pre-construction

Hydro 2 Geology, Hydrogeology

As above. The CEMD/CEMP will contain information on track construction over peatland/ GWDTE with due regard for key principles set out in the joint SNH/FCE guide to floating roads on peat , including:



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and Hydrology

identification of further temporary tracks if necessary;

use of the minimum length of track possible within sensitive habitats; and

adherence to best practice in track construction.

Floating road construction will comprise a layer of geotextile overlaid by approximately 50 cm of crushed concrete/hardcore. Where floating roads are proposed to be a permanent installation across areas of GWDTE/peatland, pipes and channels will also be installed beneath the road as a part of the preconstruction drainage management plan.

EC 1 also will apply.


Pollution Impact from Silt-laden Runoff:

Surface runoff containing silt, particularly during and after rainfall events, has the potential to enter the watercourses in the vicinity of works.

The CEMP and associated DMP would identify potential sensitive environmental receptors, and all watercourses and drains, including ephemeral or seasonal water features within the LOD of the Proposed Development. This would ensure issues associated with smaller water features, hydraulically linked with downstream sensitive receptors such as the River Thurso or Caithness Lochs, are addressed.

Pre-construction


As above. The CEMD/CEMP will specify measures to manage silt and fines from works sites. At a minimum these will follow SEPA 'Guidelines for Water Pollution Prevention from Civil Engineering Contracts' and 'Special Requirements', together with other best practice measures adopted by the Applicant.

Pre-Construction

Hydro 5 Geology, Hydrogeology

As above. The CEMD/CEMP will define pollution response measures and specify measures to manage silt and fines from work sites.

The CEMD/CEMP would include:

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and Hydrology

a pollution risk assessment of the site and the proposed activities;

identification of all water bodies that may be affected by the works and temporary discharge points to these watercourses;

planning and design of appropriate pollution control measures during earthworks and construction;

management of the pollution control system, including dewatering of excavations away from watercourses, deployment of pollution spill kits, silt entrapment measures and designated fuelling sites at safe distances away from watercourses;

contingency planning and emergency procedures; and

ongoing monitoring of construction procedures to ensure management of risk is maintained.

The location of spill kits and other pollution control or emergency response equipment would also be included in the CEMD/CEMP. This would enable any potential pollution incident during the construction of the Proposed Development to be managed appropriately.

GEN 1 would apply.


As above. The CEMD/CEMP would include measures to ensure:

greenfield run-off (i.e. non-silty surface water flow that has not yet passed over any disturbed construction areas) would be kept separate from potentially contaminated water from construction areas as much as possible;

interceptor ditches and other drainage diversion measures would be installed, immediately in advance of any excavation works, in order to collect and divert greenfield run-off away from construction disturbed areas;

greenfield run-off would be discharged into an area of vegetation for dispersion or infiltration. Silt traps, sand bags, silt fencing, anchored

Pre-construction


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straw bales or discharge through a filter medium of selected granular fill may also be installed at the discharge point;

stormwater ditches would follow the slope of the ground with a generally constant depth to ditch invert and shallow longitudinal gradients; and

interception and diversion of clean runoff would prevent significant disruption to shallow groundwater flow, flush areas and blanket bogs reducing the flow of water onto exposed areas of rock and soil, thereby reducing the potential volume of silt-laden run-off requiring treatment.


As above. All earth moving works or similar operations would be carried out in accordance with BSI Code of Practice for Earth Works BS6031:1981. While it is acknowledged that best practice to minimise run-off would be to undertake construction during the driest period of the year, given the location of Proposed Development, there are likely to be significant periods of rainfall throughout the year.

Construction


As above. The CEMD/CEMP will define arrangements for materials stockpiles. Temporary stockpiles associated with excavations for individual towers would be located a minimum of 30 m from the edge of watercourses. This would extend to a minimum of 75 m from the edge of the River Thurso SAC.

Construction


As above. All excavations would be backfilled as soon as practicable. Construction


Pollution Impact from Chemical Contaminated Runoff:

Pollutants such as chemicals or fuel

The CEMDCEMP will specify arrangements for the storage and management of all construction liquids such as fuel or hydraulic fluids. This will include measures such as:

no mobile storage of fuels or refuelling activities would occur within 30 m of any drain, ditch or watercourse;

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used during construction may be mobilised through mechanical leaks or spillage and carried in surface drainage.

no permanent or fixed storage of fuel would occur within 100 m of any drain, ditch or watercourse;

all fuel and other potential chemical contaminants would be stored in accordance with best practice procedures, including a designated fuelling site located at a safe distance from existing watercourses in appropriate impermeable bunded containers/areas which would be defined within the CEMD/CEMP;

fuel stores would designed to capture any leakage, whether from a tank or from associated equipment such as filling and off-take points and sighting gauges which would be located within the bund;

oil booms and soakage pads would be maintained in the site compounds and spill kits would be kept in all vehicles to enable a rapid and effective response to any accidental spillage or discharge;

construction staff would be trained in the effective use of spill equipment; and

construction vehicles and plant would be regularly maintained and all maintenance, fuelling and vehicle washing would be undertaken on appropriate impermeable surfaces away from watercourses in order to minimise risks of leaks to soil and surface waters.


As above. The CEMP would provide emergency response contacts, reporting procedures and procedures for dealing with all potential pollution incidents during the construction of the Proposed Development. This would include detailed procedures to be taken in the event of an incident or emergency (including procedures for positioning and movement of plant, use of spill kits, communication etc.).

Construction


Impact on Integrity of Banking:

Vertical vehicular pressure on or close

Construction vehicles and construction working areas would, where practicable, maintain a stand-off distance of 10 m from the edge of watercourses. In the event that construction activity is required within these

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to the sides of watercourses can detrimentally affect the structural integrity of the banks.

limits detailed method statements and risk assessments will be developed by the main Contractor and set out in the CEMP and DMP.


As above. The CEMP will define measures for water crossings. Where watercourses (small ditch crossings) require to be crossed by construction vehicles the following principles will be applied:

on sloping ground, water courses would be crossed predominantly by tracked machines;

level water features would be crossed by placing bog mats across the feature to minimise any damage being caused to the bank or bed;

should any drainage ditches become damaged or blocked as a result of construction vehicles crossing them, these would be repaired or cleared by construction staff as soon as agreed works can be implemented; and

repair works would refer to the baseline conditions of the affected water body as described in the DMP.

Construction


Direct Discharge of Untreated Foul Drainage:

There is potential for direct discharge of untreated foul sewage from temporary welfare facilities to watercourses or water bodies.

The CEMP will require that welfare facilities would either drain to a suitably maintained portable septic tank or connect directly to the foul sewer. If portable septic tanks are to be used, these would be maintained and removed from the Site on a regular basis by a suitably-licensed supplier.

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Disruption to Artificial Land Drainage:

Damage to existing land drainage may occur as a result of access and/or tower foundation excavation and construction.

A Drainage Management Plan (DMP) will be developed prior to construction works as part of the CEMP.

The DMP would be a 'living document' which would evolve and be updated throughout the construction life of the Proposed Development.

This will include:

a plan of known existing land drainage;

preparation of site specific EMPs for all works sites;

identification of drainage flow paths and potential pollution sources. Such sources include car parks, delivery and fuel/chemical storage areas, oil separator equipment, excavations, and any other high risk areas that could give rise to pollution (oil/chemical storage areas, refuelling areas, concrete batching and wash out areas etc.);

measures to ensure that natural drainage paths are not blocked or altered by construction, unless alternatives are put in place;

proposals for site drainage during the works (to inform the design and positioning of silt management measures and interceptors); and

a Drainage Mitigation Register, which would include drawings of intended and installed drainage measures and information regarding on-going maintenance. This may comprise a number of separate drainage plans (e.g. drawings, specifications and method statements) for each of the main phases of works, works areas, and works in proximity to sensitive receptors.

Pre-Construction


As above. The DMP should be updated with records of any drains encountered during construction where appropriate.

Each individual drainage feature and mitigation measure should be constructed and functional prior to construction of the infrastructure of the Proposed Development which they are intended to service. If this is not

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feasible then the drainage features should be constructed at the same time as the proposed infrastructure or temporary measures should be installed.


As above. Drains will not be severed by the construction process without temporary drainage diversion being put in place. At post-construction stage permanent diversions would be required. These would not avoid foundation areas.



As above. Where watercourses and ditches are to be crossed, new or upgraded culverts should be installed as required. Culvert design would be discussed and agreed with SEPA and constructed in accordance with SEPA guidance.

Construction


As above. However should soil compaction occur new drains will be installed to assist the natural drainage, as agreed with land owners.

SLA 1 and SLA2 also apply.

Construction


As above. Any settlement/soil depression as a result of foundation works, or tower placements will be topped up as part of reinstatement works.

Reinstatement


Dewatering of foundation excavations:

Potential impact on groundwater and surface water conditions in terms of flow disruption and mobilisation of sediments as a

Where towers will be located within peat, alluvium or other low strength materials, the CEMP will define measures for the management, removal and disposal of any water ingress into excavations to preserve the integrity and water content of the surrounding ground and to minimise the need for water disposal.

Measures for management of the peat resource described in SLA 2 to SLA 10 will be followed.

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result of foundation excavations causing a build-up in surface waters due to surface water generated.


Potential impact on Private Water Supplies (PWS) during construction.

A method statement will be developed detailing all mitigation measures to be delivered to secure the quality, quantity and continuity of water supplies to properties which are served by private water supplies at the date of this consent and which may be affected by the Proposed Development. The method statement shall include water quality sampling methods and shall specify abstraction points. .

Pre-construction


Potential to impact Scottish Water assets within the LODs of the Proposed Developments.

Confirmation of locations of all Scottish Water assets and PWSs will be sought and a plan included within the CEMP prior to construction commencing. All identified assets will be marked out on the ground and disturbance of any identified asset will be avoided.

Pre-Construction.


Effect on flood risk – especially adjacent to the Burn of Garth and the tributary of the Burn of Rattar.

The CEMP will include measures to ensure there is no increase in associated flood risks. Measures would include:

all works in flood plains should be undertaken in the driest (summer) months to minimize the impact of potential storms;

excavations would be dug and left open for the minimum of time, then immediately back-filled once construction is complete;

during extreme weather conditions, Contractors would move all heavy plant out of the identified risk areas. The CEMP would include maps showing flood zone areas and instructions on where to move plant to; and



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construction works would not take place during extreme flood conditions or in floodplain areas that are inundated.


Various. Mitigation measures would be monitored by an Environmental Clerk of Works (GEN 2) throughout construction.

Construction

SLA 1 Soils, Landuse and Agriculture

Impacts on soils through loss as a result of excavations for foundations and removal of excess soil.

The CEMD/CEMP will provide specifications for the management of vegetation and soils which will include for the minimisation of avoidable removal, stripping and segregation proposals and storage arrangements.

Construction


Changes in soil quality arising from mixing of soils and mixing of peat.

Specific measures in the CEMD/CEMP will define procedures for the management of soils to enable conservation of soil resources for potential use elsewhere. Such measures may include for example;

Mineral Topsoils: could be stripped as a single unit and stored, either temporarily for replacement or transferred to a location identified for their longer term use in landscaping;

Organic Topsoils: where these soils are over 300mm thick, they would be stripped from the underlying mineral subsoils and stored separately. Where the topsoil is less than 300 mm thickness they would be stripped with underlying material as a single unit to ensure practical handling can take place. The resulting soils will be treated as organic topsoils and stored separately from mineral topsoils for reuse as a single unit, either as replaced soil around tower foundations or in locations identified for longer term use in landscaping; and

Subsoils will be excavated as a single unit. The quality of these soils is such that no significant deterioration in quality will be expected to arise from mixing of horizons above slowly permeable layers. Similarly deeper

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subsoil horizons, including those which exhibit slowly permeable characteristics will be treated as a separate unit where practicable.

SLA 6 and SLA 7 also apply relating to peat management.


As above. Soil handling to be carried out in as dry conditions as possible to prevent soil deterioration - and preferably when each soil horizon or layer is drier than the Plastic Limit, as defined in BS 1377.

Where soil handling at Field Capacity care must be taken to avoid unnecessary excavation and handling.

Construction


Changes in nutrient status of soils during storage, including release of nutrients from stored soils to support certain habitat types.

Where temporary soil storage is established both mineral and organic topsoils will be stored, separately, on geotextile underlay (to protect underlying soils).

The outer faces of the mounds would have gradients which minimise the risk of slumping and would take account of the underlying ground conditions, including topography and the nature of the mounding material.

Construction


As above. Soil storage at tower locations and along the cabling route will be temporary and stored for no longer than a period of 4 weeks, if practicable.

Construction

SLA 6

Soils, Landuse and Agriculture

As above. Soil stored for more than a 4 week period will be maintained to stabilise the mounds and reduce erosion.

Construction


Impacts on peat :

Loss of peat volume.

Micrositing of individual towers and cable route will seek to avoid peat deposits and in particular minimise location of towers on areas of deep peat.

Construction


As above. The CEMD/CEMP will include specific proposals regarding peat (i.e. peat at thicknesses of greater than 500 mm). This is limited within the LOD of the Proposed Development.

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Measures for the management of the peat resource within the CEMD will include:

Peat depth surveys where cable route of tower locations are confirmed by micrositing to be located within areas of peat resource;

where peat is to be removed it would be excavated using a tracked excavator where possible;

tracks and trucks would only run on mineral soils below the peat or on site roads or established areas of hardstanding to avoid structural degradation of the peat to be recovered (where possible);

where possible, peat will be excavated and emplaced directly to its final position, with turves removed separately and reinstated at the surface, to minimise loss of moisture and integrity of the peat;

if this is not possible specific method statement and risk assessment for handling peat will be development by the main Contractor and agreed with the ECoW;

if localised storage of peat is required, water levels in the peat will be maintained as far as possible through use of peat ponds utilising plastic liners whilst awaiting reinstatement; and

measures ensuring peat drainage is retained (Hydro 15) will be employed.


As above. Where towers are proposed in areas of peat, foundation design and installation will have regard to minimise the extent of peat excavation. This will be determined in terms of engineering requirements however any solution shall ensure that minimisation of peat excavation is fully considered.

Hydro 15 applies.

Construction


As above. Where cabling is proposed in areas of peat, the trench design and groundworks will have regard to minimise the extent of peat excavation. This will be determined in terms of engineering requirements however any solution shall ensure that minimisation of peat excavation is fully considered.

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Hydro 15 applies.


Impacts on peat :

Potential release of carbon dioxide due to disturbance of peat.

SLA 7 and SLA 8 apply (management of peat resource/ reducing excavation). Construction


Agricultural disruption: Disruption to agricultural activity including access restrictions during construction work.

A detailed construction programme will be determined in consultation with landowners and occupiers and will incorporate appropriate levels of access and activity.

Pre-construction / construction


Fragmentation of agricultural holdings.

SLA 12 applies. Pre-construction / construction


Isolation and severance of agricultural land from wider holdings.

SLA 12 applies. Pre-construction / construction

SLA 15 Soils, Land use and Agriculture

Forestry disruptions Disruption to forestry operations during construction.

A detailed construction programme will be determined in consultation with the landowners and occupiers currently engaged in forestry operations and would incorporate appropriate levels of access and activity.

Construction

SLA 16 Soils, Land use and Agriculture

Disruption/access restrictions to areas of land in use for forestry and

Wayleave rights of access will be held by the operator of the OHL and cabling for ongoing maintenance and emergency access. Arrangements will be

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agricultural land for maintenance.

made with landowners and occupiers to, as far as practicable, arrange access across land in advance.

TT 1 Traffic and Transport

TA traffic management plan (TMP) will be developed and will include:

a. The routeing of all traffic associated with the Proposed Development on the local road network;

b. Measures to ensure that the specified routes are adhered to, including monitoring procedures;

c. Details of all signage and lining arrangements to be put in place;

d. Provisions for emergency vehicle access;

e. Identification of a nominated person to whom any road safety issues can be referred; and

f. A plan for access by vehicles carrying abnormal loads, including the number and timing of deliveries, the length, width, axle configuration of all extraordinary traffic accessing the site.

TT 2 HGV movements to and from the site (excluding abnormal loads) during construction of the Proposed Development shall be limited to 07.00 to 19.00 Monday to Friday, and 07.00 to 16.00 on Saturdays, with no HGV movements to for from site taking place on a Sunday or on national public holidays, unless otherwise approved in advance in writing by the planning authority.

Noise 1 Noise Residential amenity:

Noise from construction activities.

Construction work which is audible from any noise-sensitive receptor shall only take place between the hours of 07.00 to 19.00 on Monday to Friday inclusive and 07.00 to 16.00 on Saturdays, with no construction work taking place on a Sunday or on national public holidays. Outwith these specified hours, development on the site shall be limited to maintenance, emergency works, dust suppression, and the testing of plant and equipment, unless otherwise approved in advance in writing by the planning authority.


Noise 2 Noise As above. Community liaison arrangements will be established to provide a mechanism to respond to community concerns arising in connection with noise.

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Noise 3 Noise Residential amenity:

Noise from construction traffic.

TT 1 applies.

The TMP will be developed to minimise construction traffic through settlements and in the vicinity of nearby dwellings where practicable. Alternative routes will be used on a rotational basis to minimise impacts at individual dwellings/settlements, as required.



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