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Glenlivet Development Project EIA Non-Technical Summary DONG Energy

Assignment Number: A100231-S00 Document Number: A-100231-S00-TECH-009

Xodus Group Ltd Xodus House 50 Huntly Street Aberdeen AB10 1RS UK T +44 (0)1224 628300 E [email protected] www.xodusgroup.com

Non-Technical Summary A100231-S00

Client: DONG Energy Document Type: Technical Note Document Number: A-100231-S00-TECH-009

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Glenlivet Development Project EIA – Non-Technical Summary Assignment Number: A100231-S00 Document Number: A-100231-S00-TECH-009 2

Document Title:

Glenlivet Development Project Environmental Statement

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UK-EDR-00-TEPU-701015

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Revision: 01 Status: AFC

Rev Date: 22 Oct 14 Page

WEST OF

SHETLAND

PROJECTS

© This document is the copyright and property of TOTAL. All rights reserved. This document shall not be reproduced in any form or by any means, transmitted,

lent or used for any purpose other than for which it was provided without the prior written consent from an authorised member of staff of TOTAL.

Glenlivet Development Project

Environmental Statement

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Rev Date: 22 Oct 14 Page 2 of 251

DOCUMENT REVISION HISTORY SHEET

Rev Date Status Reason for Revision

01 22 Oct 14 AFC Issued for Construction

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STANDARD INFORMATION SHEET Project (Installation) Name: Glenlivet Development Project

DECC Reference number: D/4169/2014

Type of Project: Development of a gas-condensate field with subsea wells, manifold, pipelines and an umbilical

Undertaker name: TOTAL Exploration and Production UK Ltd

Undertaker address: Crawpeel Road, Aberdeen, AB12 3FG

Licensees/Owners: TOTAL Exploration and Production UK Ltd 80%

DONG Exploration and Production UK Ltd 20%

Short description: Glenlivet is a gas-condensate reservoir located in Block 214/30a of the UK continental shelf, approximately 70 km north-west of the Shetland coast. The reservoir will be developed by drilling two production wells. These wells will be connected to a new manifold and gas and condensate production tied-back to the existing Laggan-Tormore production flowlines by a new subsea Glenlivet production flowline. Monoethylene glycol (MEG, a hydrate inhibitor) and service fluids will be provided to Glenlivet through connection of new pipelines to the nearby Edradour Area Development. Control of the Glenlivet facilities will be from the Shetland Gas Plant in Sullom Voe via a new umbilical from Edradour. The water depth at the Glenlivet drill centre is 435 m, 295 m at the planned connection to the Edradour Area Development and 386 m at the connection to the Laggan-Tormore flowlines. This Environmental Statement presents the findings of an assessment of the environmental impacts of the drilling of two wells, installation of the Glenlivet facilities (including pipelines) and of the operation, maintenance and decommissioning of the development.

Key Dates: First drilling – 2015;

Installation of subsea structures, flowlines and umbilical – 2016 to 2018; and

First gas – 2018.

Significant environmental impacts: None

Statement prepared by: TOTAL Exploration and Production UK Ltd and Xodus Group

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Non-Technical Summary

This non-technical summary has been made available as an integral part of the Glenlivet Development Project Environmental Statement and also as a standalone document.

S.1 INTRODUCTION S1.1 GLENLIVET DEVELOPMENT PROJECT TOTAL Exploration & Production United Kingdom Ltd (TEP UK) is planning to develop the Glenlivet field in UK continental shelf Block 214/30a to produce gas-condensate. The drilling of two wells and installation of pipelines and other structures will allow production from the Glenlivet field through the Laggan-Tormore pipelines into the Shetland Gas Plant (SGP), both of which are currently being installed by the TOTAL Exploration and Production UK (TEP UK) operated Laggan-Tormore Development.

The Glenlivet field is located approximately 70 km north-west of Shetland and approximately 95 km from the UK/Faroe median line in a water depth of approximately 435 m (Figure S.1).

Figure S.1 Glenlivet Development Project location

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An Environmental Impact Assessment (EIA), as reported in this Environmental Statement (ES), has been carried out in accordance with the requirements of the Offshore Petroleum Production and Pipelines (Assessment of Environmental Effects) Regulations 1999. The regulations require the undertaking of an EIA and the production of an ES for the certain types of offshore oil and gas developments that may have a significant effect on the environment. This ES considers impacts from the installation of the structures summarised below and as shown in Figure S.2:

• Drilling of two wells and installation of associated structures at the Glenlivet drill centre;

• Installation of a new manifold next to the two Glenlivet wells (for combining and controlling production

flows from each for onward distribution);

• Installation of a new 35 km 12" production line (and associated subsea structures) to link Glenlivet to

the Laggan-Tormore production flowlines via Edradour. The tie-in point will be the In-Line Tee 3

(ILT3) location pre-installed on the Laggan-Tormore flowlines;

• Installation of a new 18 km 6" monoethylene glycol (MEG) line and a 2” service line piggy-backed

onto it to link Glenlivet to Edradour; and

• Installation of a new 19.2 km combined power/communications/hydraulic/chemical umbilical linking

Glenlivet with Edradour.

S1.2 PROJECT SCHEDULE Drilling of both Glenlivet wells is expected to occur in the first half of 2015, with completion of both wells the following year. The Glenlivet pipelines, subsea structures and the umbilical would be installed during summer 2017, with tie-in and commissioning in mid-2018. First gas from the Glenlivet field is expected in 2018. The lifespan of the Glenlivet Development Project in terms of production is expected to be in the order of 15 years.

S1.3 THE ENVIRONMENTAL IMPACT ASSESSMENT PROCESS An EIA is a process designed to identify, interpret, predict and communicate information about the impacts of proposed developments. The completion of an EIA is a legal requirement for projects of this type. The ES (this document), is the documented outcome of this process; however, elements of the process continue through the development of the Project and into operation through TEP UK’s Environmental Management System. As the Project progresses through detailed design, construction, installation and subsequent operations, environmental assessment will be ongoing. The outcome of EIA and any final decisions still to be made will be reported in the appropriate detailed consent submissions to the Department of Energy and Climate Change (DECC), the competent authority, as appropriate. Central to a pro-active environmental assessment is the requirement to identify issues that could have an impact on the environment and potential cumulative impacts. Once identified, these issues have to be assessed to define the level of potential risk they present to the environment, so that possible measures can be taken to remove such risk through design or operational measures (known as mitigation measures).

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Figure S.2 Glenlivet Development Project

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S1.4 CONSIDERATION OF ALTERNATIVES A key element of the EIA process is the consideration of alternatives prior to selecting the preferred option; this ensures that the environmental impacts and benefits of different options are fully explored, taking into consideration safety, operability and cost issues.

Within the west of Shetland area, the only gas processing and export routes to the UK market are the Laggan-Tormore, Edradour and Clair Area systems. Early in the development process it became clear that tie-back options to the Clair Area were not technically or commercially feasible. Given that the relative size and the composition of the Glenlivet reservoir is such that a surface facility (i.e. a platform) is not economically viable and does not offer any technical advantage, a subsea tie-back to the SGP direct or into the Laggan-Tormore flowlines were the only two remaining main options. The main routes with sub-options considered for the Glenlivet Development Project were:

• Production tie-in direct to the SGP;

• Production tie-in to Laggan-Tormore pipelines at the hot-tap tee 1 location (HTT1); and

• Production tie-in to Laggan-Tormore pipelines at the ILT3 location.

These routing options are shown in Figure S.3.

Subsea tieback to the Laggan-Tormore flowlines at either ILT3 or HTT1 was preferred, in comparison to the direct tieback to the SGP, because these options have a lower cost and avoid the need to route a further pipeline through the potentially sensitive nearshore habitats of Yell Sound and Orka Voe, Shetland. Following further evaluation, a production tie-back to ILT3 was selected in preference to a new route to HTT1 because the existing structures at ILT3 provide all the necessary facilities to simplify tying-in the Glenlivet production flowline. In comparison, the features at the HTT1 location are more limited and require cutting into the pipeline (‘hot-tapping’) to make a connection.

The Laggan-Tormore Development uses continuous injection of MEG to prevent hydrates (ice-like solids) forming in the produced fluids as they flow to the SGP. The Glenlivet Development Project must also use this method in order that its production is compatible with Laggan-Tormore fluids during commingled transport to the SGP. Tie-in to the MEG supply line at Edradour was selected as this provides the shortest route for the new pipeline (18 km).

Subsea control options considered for Glenlivet were:

• Install a new umbilical extension from Laggan to Glenlivet;

• Install a new umbilical from the SGP to Glenlivet; and

• Install a new umbilical extension from Edradour to Glenlivet.

The installation of an umbilical extension from Laggan to Glenlivet was ruled out early on due to insufficient subsea termination capacity at Laggan. Technical studies have shown that it is feasible to extend the Laggan-Tormore control system from Edradour to Glenlivet. This local connection option was therefore selected over a direct link between SGP and Glenlivet because it has a lower cost, avoids the requirement for earthworks at the SGP, avoids installation of an umbilical through Orka Voe and Yell Sound and since the direct link provides no technical advantage.

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Figure S.3 Glenlivet Development Project route options

S.2 THE DEVELOPMENT S2.1 Glenlivet reservoir The Glenlivet fluids are predicted to be a light gas-condensate with a condensate-gas ratio of approximately 16 barrels per million standard cubic feet (i.e. mostly gas with low levels of condensate). It is also expected that some water from the reservoir will be produced. The reservoir fluid contains very low levels of carbon dioxide, hydrogen sulphide and mercury, which simplifies the complexities around production.

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S2.2 Wells and drilling Given the harsh environment experienced to the west of Shetland, the Glenlivet Development Project wells will be drilled from a semi-submersible drilling rig which has been designed to withstand the ocean conditions (Figure S.4).

Figure S.4 An example of the type rig that could be used to drill the two Glenlivet wells

Both wells will be drilled from one rig location; both will be deviated from the point at which the drilling takes place on the seabed in order to reach the reservoir targets. The wells will be drilled as a sequence of sections, the top section being the widest and the sections below being of successively reduced diameter. The wells will be drilled using drilling muds to cool the rapidly rotating drill bit, lubricate the drillpipe as it turns in the well, carry rock cuttings to the surface and prevent the wall of the well from collapsing. It is anticipated that the drilling muds used will be water based, and that the cleaned cuttings with associated residual mud will be discharged to sea. Considering well design, it is expected that a maximum of 2,650 tonnes of mud and cuttings will be discharged to the marine environment for each well (a combined total of 5,300 tonnes for both wells). For the shallower sections of each well, cuttings discharges will occur directly to the seabed around the open well bore, whilst for deeper sections a closed circulation system will be used whereby mud and cuttings are returned to the drilling rig for processing/cleaning prior to the cuttings being discharged and the mud recycled for use. These overboard discharges will be via a caisson terminating above the sea surface; the solid components will descend through the water column to spread thinly over an area of seabed around the well location.

It is expected that vertical seismic profiling (VSP) may be required on both wells; like surface seismic surveys, this uses a loud noise source to generate seismic waves to pass through the Earth’s layers and detectors to measure the reflection returns. However, in VSP either the energy source or the detectors (or sometimes both) are located down the well. The pattern of reflections will be used to establish the geological structure of the rock formations through which each well passes. This adds significant site-specific detail, serving to ground truth the sub-surface structural information gained from earlier remote seismic surveys.

S2.3 Subsea structures The two wells, over which overtrawlable protection structures will be installed, will each be connected by short sections of pipeline (called rigid jumper bundles) to the Glenlivet manifold. The manifold will also be designed to be overtrawlable to provide protection from fishing gear interactions and dropped objects. A number of additional subsea structures will be installed between the Glenlivet manifold and the Edradour and ILT3 locations, including flowline end termination units (FLETs). Examples of the overtrawlable structures to be used to protect these pieces of equipment are shown in Figure S.5.

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Figure S.5 Example of the overtrawlable protection structure that will be installed as part of the Glenlivet Development Project

S2.4 Pipelines Production fluids (i.e. gas, condensate, water) from the Glenlivet reservoir will be transported by a new 35 km pipeline to the Laggan-Tormore production flowlines. As outlined above, MEG will be added to the produced fluids to prevent formation of hydrates in the production system; this will be supplied via a new 18 km pipeline running from Glenlivet to the Edradour Area Development drill centre. The service line functionality (i.e. provision of chemicals) included in the Laggan-Tormore and Edradour Area Development systems will be extended to Glenlivet (from Edradour) using a small service pipeline which will be piggy-backed on the MEG pipeline. Control of the Glenlivet Development Project facilities will be provided by a new 19.2 km umbilical from the Edradour manifold to the Glenlivet manifold. The umbilical will provide the hydraulic, electric, fibre optic and chemical services required by the Glenlivet Development Project.

The base case for the installation of the pipelines is that the production flowline, the MEG and piggy-backed service pipeline and the umbilical will each be laid into a very shallow trench created using a shallow plough device (essentially to clear smaller boulders to either side of the route, and not to specifically bury the pipeline). A boulder grabber will be used to remove larger boulders from the pipeline route prior to installation. The pipelines will then be covered over with rock. However, based on the experience gained during the design and installation of the Laggan-Tormore pipelines in this area, boulders may be too numerous in some areas to allow for effective ploughing clearance. The alternative option of adding rock material as a bed for the pipelines to lie on, followed by additional rock protection on top has therefore been assessed in this ES, as it constitutes the solution with the greatest potential environmental impact (i.e. it is considered ‘worst-case’). The installation of the pipelines would involve the use of a rock placement vessel to install a rock carpet on the seabed, upon which the pipelines will be placed using a pipelay vessel. Following pipelay, further rock will be placed on top of the pipelines for protection and stabilisation purposes. The final installation solution will be determined from 2014 survey data and on-going engineering work.

S2.5 Existing facilities and modifications The Laggan-Tormore and Edradour Area Development systems have been designed to allow future developments in the west of Shetland area to easily make use of the infrastructure they will provide. As such, only minor work to connect the Glenlivet facilities into the existing systems is required. Additionally, as the produced fluids from Glenlivet will be similar to those from Laggan-Tormore, the only change to the SGP onshore will be minor modification of the controls infrastructure. No additional groundwork (e.g. clearance, peat storage, concrete pads, etc.) would be required as part of these changes.

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Produced water from Glenlivet will be commingled with Laggan-Tormore and Edradour produced water. The total produced water from Laggan-Tormore-Edradour-Glenlivet will be within the existing capacity of the effluent water treatment systems at the SGP and so Glenlivet production will not increase the effluent water discharge flowrate from that assessed under the Laggan-Tormore and Edradour developments.

During the operational phase of the Glenlivet Development Project, TEP UK will endeavour to make use of the same chemicals currently used by the Laggan-Tormore-Edradour developments. To align with this, a variation to the SGP Pollution Prevention and Control (PPC) permit will be undertaken by its operators (TEP UK) prior to production, to cover additional chemical requirements. The Glenlivet Development Project will not result in increased power use at the SGP.

S2.6 Commissioning activities Well testing following drilling is a means of assessing reservoir performance by measuring flowrates and pressures under a range of flow conditions. A limited amount of hydrocarbons are allowed to flow from the formation being tested which, in the absence of export facilities, is usually disposed of through flaring. One well test will be performed for a maximum duration of 96 hours at each of the two Glenlivet wells, during which a maximum of 2,000 tonnes of produced hydrocarbons will be flared from each well.

Prior to commencement of production through to the SGP, the following testing and pre-commissioning activities will occur for the pipelines:

• Flooding of the offshore pipelines with filtered and treated water (most likely seawater, treated with

small amounts of corrosion inhibitor and biocide);

• Cleaning to remove any solid foreign material from the pipeline and to prevent damage to valves and

instrumentation, undertaken as part of flooding operation;

• Pipeline measurements to demonstrate that the pipelines are free of buckling, denting, etc.;

• Baseline internal pipeline inspection using a remote controlled device (pigging) to provide benchmark

data for comparison with future inspections (requirement for this to be determined at the time of

commissioning);

• Strength test of the offshore pipelines;

• Leak test of entire system once fully tied-in; and

• ‘De-watering’ to remove all water from pipelines prior to the introduction of hydrocarbons. The leak testing could involve minor discharges to sea at any point along the pipelines, whereas de-watering is expected to result in discharges of water from the pipelines offshore at either the Glenlivet manifold or the ILT3 location.

S2.7 Operation and maintenance The offshore Glenlivet Development Project facilities will be operated remotely from the SGP via the umbilical. Valves will be actuated through the subsea control system and small volumes of hydraulic fluid will be discharged to sea at each actuation event. No well maintenance (‘workover’) is anticipated on the Glenlivet wells over the life of the field, given their simple configuration. Operational pigging of the Glenlivet flowline is anticipated once in every five year period; such an operation will require support from surface vessels.

S2.8 Decommissioning The infrastructure associated with the development will be decommissioned when production is no longer economically viable. The lifespan of the Glenlivet Development Project is expected to be in the order of 15 years. The expected decommissioning philosophy for the infrastructure associated with the Glenlivet Development will be to remove all subsea structures and material. Within this 15 year time-frame there may be changes to the statutory decommissioning requirements as well as advances in technology and knowledge. TEP UK will therefore aim to utilise best recognised environmental practice during all decommissioning operations in line with legislation and guidance at the time.

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S.3 ENVIRONMENT S3.1 Physical environment The west of Shetland area, within which the Glenlivet Development Project is located, is characterised by persistent long-period ocean swells, complex current regimes and rapidly changing weather conditions. The deep water over the edge of the continental slope west of Shetland is exposed to a large fetch and strong winds, particularly from the west and south-west. These conditions generate an extreme wave regime in the area, which is more severe than that experienced in the North Sea.

Winds can occur from any direction in the vicinity of the Glenlivet Development Project, but the predominant winds throughout the year are from the south and west. The dominant wind speeds throughout the year are moderate breezes. Strong winds can occur throughout the year, but are more frequent during the winter months.

The Glenlivet Development Project is located on the shelf break of the west of Shetland continental shelf and upper part of the continental slope (eastern flank of the Faroe-Shetland Channel). The approximate water depth at the drill centre is 435 m. The water depth at the Glenlivet umbilical and MEG tie-in location at Edradour is approximately 295 m and the water depth at the ILT3 pipeline tie-in location is approximately 386 m.

TEP UK and its Project partners have undertaken a number of surveys in the west of Shetland in support of the Glenlivet Development Project and has entered into a data sharing agreement with a number of other parties to access recent surveys for other west of Shetland developments (e.g. Chevron Rosebank Development) where these might be relevant to Glenlivet.

In the vicinity of the Glenlivet drill centre, the seabed is of uniform composition, comprising slightly gravelly sand with occasional cobbles, boulders and small mounds or ‘raised features’. Between Glenlivet and Edradour, the seabed sediments start as silty gravelly sand with occasional cobbles and boulders, but from halfway to Edradour this is broken up with numerous extensive patches of sand. Several areas of rippled and megarippled sand are also present, with a typical wavelength of about 15 m and height of less than 0.5 m. In the vicinity of Edradour itself, the seabed is varied, comprising a thicker veneer of sand in some areas (including the Edradour drill centre itself), a series of linear sand deposits though to be mobile and on the result of local seabed currents, and a thin veneer of sand associated with coarse sediment, comprising pebbles, cobbles, silt and clay in other areas.

Typical images from the Glenlivet drill centre are shown in Figure S.6.

Shelly gravelly sand with cobbles and small boulders. Visible fauna: squat lobsters, pencil urchins, sponges, fish

Shelly gravelly sand with cobbles. Visible fauna: squat lobsters, sponges

Figure S.6 Example images of the seabed in the vicinity of the Glenlivet drill centre

The seabed sediments between Edradour and the ILT3 tie-in point at the Laggan-Tormore pipelines are a thin veneer of sand less than 0.5 m thick. Within the eastern part of the route (closest to Edradour), this sand overlies soft to stiff sandy clay with occasional gravel, sand layers and boulders, whereas towards the western end the underlying sediments are very soft to soft well layered pebbly clay with occasional gravel

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layers. The seabed is scattered with numerous boulders up to 1.5 m in height and surface megarippled sands. Numerous scars are present, including some deep anchor scars expanding radially from the Edradour 206/4-2 exploration wellhead. Typical images from the Edradour to ILT3 route are shown in Figure S.7.

Silty to fine medium sand with cobbles, pebbles and boulders. Visible fauna includes anemone, ling and polychaetes

Silty fine to medium sand with cobbles and pebbles. Visible fauna includes feather star

Figure S.7 Example images of the seabed between Edradour and ILT3

S3.2 Biological environment Plankton

Plankton forms the basis of the much of the marine food web. The composition and abundance of plankton communities varies throughout the year and is influenced by physical parameters such as temperature, salinity and water inflow. In the north-east Atlantic, species of a single-celled plant group known as dinoflagellates, especially Ceratium, dominate the phytoplankton community. The small crustacean Calanus is of particular importance in the zooplankton in the vicinity of the Glenlivet Development Project. Large populations of pre-adult Calanus finmarchicus over-winter in the cold deep waters of the Faroe-Shetland Channel, migrating to surface waters during the spring where they are circulated into the North Sea by prevailing currents. During autumn, water currents return C. finmarchicus to the west of Shetland area where they sink down to the deeper waters to over-winter once again.

Benthic communities

At Glenlivet, images collected from survey work show gravelly sands with occasional pebbles and cobbles supporting sponges and encrusting bryozoans (also termed ‘moss animals’ and ‘sea mats’, these are invertebrates of approximately 0.5 mm length that filter food out of the water column). Pencil-spined urchins and squat lobsters, sea cucumbers, polychaete worms (segmented worms with bristles), anemones, and fish are also a common component of the animal types that live on the seabed (epifauna). The sponges seen were observed as isolated individuals, and no mass sponge aggregations, such as those previously encountered west of Shetland and in Faroese waters were observed in the area around the Glenlivet wells location. Similar imagery between Glenlivet and Edradour has shown patches of coarse sediment in which a relatively diverse fauna of various types of sponge attached to occasional large cobbles and boulders, echinoderms such as brittle stars, starfish, sea urchins, and occasional hermit crabs exists. This is interspersed with sand hosting a comparatively limited fauna in which the predominant species were echinoderms such as sea cucumbers, pencil-spined sea urchins and brittle stars together with occasional hermit crabs.

Around Edradour, seabed imagery shows silty fine sand with varying proportions of shell fragments with a species-poor mobile epifaunal community including occasional hermit crabs and sea cucumbers. The most frequently encountered mobile invertebrate was the squat lobster. Echinoderms were also prominent, with

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the pencil-spined sea urchin commonly appearing, alongside sea stars such as the cushion star and the seven-armed starfish. Large and distinctive sea cucumbers were also occasionally seen. Examples of the epifaunal molluscs seen were scallops (thought to be the queen scallop). Rock-attached species such as the tube worm Pomatostegus sp. have been recorded as well, with sponges seen in some photographs, along with encrusting bryozoans.

Between Edradour and the connection point with the Laggan-Tormore system (ILT3), survey results show sand becoming silty fine to medium sand, with gravel, pebbles, cobbles and possible shell fragments as the route gets closer to ILT3. Occasional larger boulders were recorded but not at densities that could be considered as stony reefs. Mobile epifaunal taxa observed included the pencil-spined urchin, sea cucumber, sea star, feather stars, hermit crabs, squat lobsters and bivalve molluscs. Sessile invertebrates (those fixed to the seabed) comprised anemones, occasional sponges and possible bryozoa. Isolated specimens of possible hard corals were previously observed at two locations on occasional boulders in the Glenlivet field in 2009, and most recently on one boulder near the ILT3 location in 2014. These small isolated occurrences are not likely to qualify as cold water reef habitat (Figure S8).

Shelly gravelly sand with cobbles and small boulder, Glenlivet field. Visible fauna: sponge, possible hard coral, pencil urchin

Small boulder near ILT3 location. Visible fauna: possible hard corals and sponge

Figure S8 Seabed photographs of small boulders with possible hard corals taken in the Glenlivet field (left) and near the ILT3 location (right)

Fish populations

A number of commercially important fish species are encountered in the vicinity of the Glenlivet Development Project (e.g. saithe, anglers, mackerel, and cod). Norway pout and whiting are the only commercially important fish species known to spawn in the waters within or around Glenlivet Development Project. Anglerfish, blue whiting, cod, common skate, herring, hake, ling, mackerel, Norway pout, sandeel, spurdog and whiting also use the waters around the Glenlivet Development Project as nursery

grounds throughout the year. Mackerel and blue whiting are known to migrate through the Project area.

Seabirds

Much of the UK coastline and offshore waters are internationally important breeding and feeding habitats for seabirds. The distribution of seabirds in the vicinity of the offshore Glenlivet Development Project area changes throughout the year, with the lowest numbers being present in the summer months during the breeding season when seabirds tend to be located inshore at

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breeding colonies. In the vicinity of the Glenlivet Development Project the northern fulmar is the most abundant species, whilst black-legged kittiwake, Atlantic puffin and common guillemot occur in moderate to high densities at certain times of the year. Seabirds, as with other marine life, can be affected to some degree by offshore activities, particularly those potentially resulting in oil spills. This vulnerability has been quantified for offshore areas on a monthly basis using the seabird vulnerability index; this index suggests that seabirds in the vicinity of the Glenlivet Development Project are classified as having an overall low to moderate vulnerability to surface pollution, with vulnerability highest between February and July.

Marine mammals

The west of Shetland area is regarded as an important area for cetaceans (whales and dolphins) in a national and international context. A number of different species are regularly sighted to the west of Shetland, with several of these species using these waters during migrations. The most abundant cetaceans in the area to the west of Shetland include the Atlantic white-sided dolphin and fin and sei whales.

The grey and harbour seal are resident breeding species in the Western Isles, Orkney and Shetland and may be encountered in the vicinity of the Glenlivet Development Project, although in low numbers. Hooded seals breed and moult on the packed ice of Arctic waters and, although on the edge of their territory in the vicinity of the Glenlivet Development Project, it is possible that they will be encountered here in low numbers.

S3.3 Conservation The JNCC has been commissioned by the UK government to identify areas that may qualify as possible offshore Special Areas of Conservation (SACs) and Special Protection Areas (SPAs) under the EU Habitats Directive and Birds Directive respectively. No such designated sites are present in the vicinity of the Glenlivet Development Project; the closest identified site offshore is the Wyville Thomson Ridge SAC, located approximately 247 km to the south.

The potential for Annex I habitat (i.e. that protected under the Habitats Directive) to be found in the Project area was considered as part of the EIA. Specifically, an assessment was undertaken on the potential stony reef habitat (sediments with sufficient cobble or boulder sized coarse material) that was recorded along the pipeline and umbilical routes. Two locations on the route between Edradour and ILT3 were identified as potentially hosting such habitat. According to the assessment of ‘reefiness’, both had low potential for qualifying as stony reef in terms of cobble and boulder composition, elevation and epifaunal cover. JNCC guidelines state that if a ‘low’ is scored in any of the reef criteria then a strong justification would be required for the area to be considered as Annex I Habitat in terms of the Habitats Directive. These survey and assessment results suggest that whilst the Project area may host rock habitats and associated fauna, the extent of any such habitat is extremely restricted and the seabed on which the development will be located does not comprise high quality rocky reef habitat of significant conservation concern under the EU Habitats Directive.

In addition to SACs, new Marine Protected Areas (MPAs) can now be designated and protected through the Marine and Coastal Access Act 2009 (MCAA) and the Marine (Scotland) Act 2010. Such sites can be created to protect areas that are classed as being important in the conservation of the nationally rare, threatened and representative habitats (and species). The Glenlivet Development Project straddles the eastern border of the Faroe-Shetland Sponge Belt MPA. This site is protected for deep-sea sponge aggregations, Atlantic and Arctic influenced offshore subtidal sands and gravels on the slope and off the shelf, ocean quahog aggregations and other geological features.

In line with expectations derived from the published literature on the distribution of deep-sea sponge aggregations, a variety of sponges have been found within the surveyed area around the Glenlivet drill centre and small areas of seabed supporting sponges have been observed between Glenlivet and Edradour and between Edradour and ILT3. Assessment of these communities at each of the three areas suggests that:

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• Around Glenlivet, the sponges are observed as isolated individuals, and no mass sponge

aggregations, such as those previously encountered west of Shetland and characterised by OSPAR

as occurring in a narrow depth band centred on the 500 m isobath, have been observed in the area.

Thus it is unlikely that the OSPAR habitat ‘deep-sea sponge aggregations’, for which the Faroe-

Shetland Sponge Belt MPA is designated, is present in the Glenlivet field area;

• Between Glenlivet and Edradour, despite areas containing several sponge species, their low extent

and coverage suggests that this does not qualify as the OSPAR deep sponge aggregations habitat;

and

• Between Edradour and ILT3, sponges were present at a far lower density than those described by

OSPAR and are not likely to constitute an OSPAR ‘deep-sea sponge aggregation’ habitat.

The indication from the survey results and other available data is that although parts of the Glenlivet Development Project sit within a wider area of potential conservation interest for deep-sea sponge aggregations, the footprint of the proposed development does not host such aggregations.

As outlined above, isolated specimens of possible hard corals were observed on occasional boulders in the Glenlivet field in 2009, and most recently at the ILT3 location in 2014. However, the small and isolated nature of these records means that these occurrences do not signify the presence of cold water coral reef habitat.

The north-west coast of Shetland is the closest land point to the east of the Glenlivet Development Project, at a distance of approximately 70 km. Shetland is comprised of a large number of islands and skerries with many coastal habitats being designated as sites of national, European and international importance. The cliff coastline supports internationally and nationally important populations of breeding seabirds and, as such, a number of sites have been identified as SACs, Ramsar sites, SPAs (including some areas for which extended marine boundaries have been proposed), National Nature Reserves and National Scenic Areas.

S3.4 Human environment Commercial fisheries

The vessel monitoring system for UK vessels over 15 m in length is a system used in commercial fishing to provide position, time at a position and course and speed of fishing vessels to monitoring agencies. This information for the latest available five years shows that fishing generally occurs across the whole continental shelf, but that intensity is greatest between the 200 and 500 m depth contours where the shelf turns into slope. This includes the waters within and surrounding the Glenlivet Development Project. These data are

supported by information provided during consultation with the Scottish Fishermen’s Federation (SFF). SFF indicated that around the Glenlivet Development Project area the 350 to 400 m depth range was heavily fished by both Scottish and English vessels as well as French, Spanish, Norwegian and Danish vessels.

Overall the quantity of demersal fish landed by fishing within Glenlivet Development Project area from UK vessels landing in the UK is classed as moderate to high in comparison to the UKCS as a whole, with pelagic landings beings moderate to very low. The total relative value of the area is categorised as moderate to high for demersal species and moderate to low for pelagic species, in comparison with the rest of the North Sea.

Other sea users

There is a long history of oil and gas activity north and west of Scotland, with the first well being drilled in 1972. In the vicinity of the Glenlivet Development Project, the Laggan-Tormore Development Project was approved in 2010 and the Environmental Statement for the Edradour Development was approved in 2012. The shipping levels in the waters to the north of Scotland are relatively low when compared with parts of the

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English Channel and North Sea. There are no submarine cables, designated wrecks, renewables development areas or military practice areas in the vicinity of the Glenlivet Development Project.

S.4 ENVIRONMENTAL IMPACT ASSESSMENT METHODOLOGY An environmental impact assessment, or EIA, is a process designed to identify, interpret, predict and communicate information about the impact of a human action. Central to a pro-active environmental impact assessment is the requirement to identify the main issues that could have an impact on the environment. Once identified, these issues have to be assessed to define the level of potential risk they present to the environment, so that possible measures can be taken to remove such risk through design or operational measures (mitigation). The potential cumulative impacts of a project also need to be assessed.

An environmental issues identification, or ENVID, workshop was carried out for the Glenlivet Development Project to identify the main potential environmental issues and highlight any necessary mitigation measures. The output from this initial exercise was used as the basis of this EIA.

In addition, a consultation meeting was held with the Department for Energy and Climate Change (DECC), Marine Scotland, the Joint Nature Conservation Committee (JNCC) and the fishing industry (Scottish Fishermen’s Federation, SFF) in the early stages of the Project. This was to discuss the Glenlivet Development Project and its environmental and socio-economic setting, and to learn what the main concerns of these key stakeholders were. Consultation has been ongoing with these stakeholders through the EIA process.

Based on the ENVID, on consultation responses and on further technical work, the main potential impacts of the Glenlivet Development Project have been identified and assessed; these impact assessments are summarised in the following sections.

As the Glenlivet Development Project progresses through detailed design, construction, installation and subsequent operations, environmental impact assessment will be on going. The outcome of this and those final decisions remaining to be made will be reported when required in detailed licences, permits and consent submissions to DECC.

S.5 SEABED IMPACTS

Impact mechanisms

The placement of the anchors by the drilling rig, the movement of the anchor chains as they sweep across the seabed and the placement of temporary installation features (such as baskets and tools) will cause localised damage to the habitats and species beneath for the duration they will remain in position. Further direct disturbance will also be caused when the anchors, chains and baskets/tools are retrieved and anchor mounds may be left on the seabed.

The installation of the pipelines and seabed structures and their associated rock protection will have direct impacts on the seabed, which may result in the loss of benthic habitat. The installation of these facilities/structures will also result in the introduction of new hard substrata (both steel and rock) that may not normally be present in the area.

In addition to the direct loss or replacement of habitat, it is likely that anchoring and installation activities will result in some sediment suspension and re-settlement around the edges of the project footprint.

Mitigation measures

A number of management and mitigation measures will be adopted by TEP UK to reduce, where possible, the potential impacts of the Glenlivet Development Project on benthic habitats and species:

• The spread of rock protection beyond the target area will be restricted through the use of a fall pipe

vessel system to ensure accurate placement of material and minimise lateral spread;

• The rock material to be used will be clean, inert and contain few entrained fines;

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• The footprint of the Glenlivet Development Project is being minimised through design, and this

includes flowline routes that are as short as possible;

• A detailed anchor pattern for the drilling rig that takes any environmental sensitivities into account will

be developed prior to mobilisation; and

• The same drilling rig will drill both wells. Should the drilling rig need to leave the site, for example

due to a break in activity over winter, the second anchor pattern will, as far as possible, occur in the

same position as the first.

Temporary disturbance

The small number of anchor placements from the drilling rig, the temporary laydown of baskets/tools and the short-term placement of a small number of mattresses during installation will cause only localised and temporary disturbance impacts (0.14 km2) and will not result in large scale changes in the benthic community. On the basis of evidence from monitoring of impacts to benthic communities from fishing trawls and taking into account the moderately energetic benthic environment at the Glenlivet Project location, it is likely that the sand and gravel habitat found in the areas within which temporary disturbance could occur will recover relatively rapidly (one to five years).

Longer-term disturbance

The total area of long-term habitat loss resulting from the installation of pipelines and infrastructure on the seabed is estimated to amount to approximately 0.87 km2 for the life of the Glenlivet Development Project; this is small in comparison to the area of similar habitat available across the wider area.

The introduction of novel substrata by the Glenlivet Development project is very small and localised and whilst it will represent a change to the benthic environment locally it is not expected to cause any widespread changes to the marine life present in the area. Ultimately, this is expected to be colonised by the same types of mobile and encrusting epifaunal animals already present on boulders in the wider area, such as faunal turfs of hydroids and bryozoans together with sea cucumbers, anemones and squat lobsters.

The area within which direct seabed and habitat impacts will occur as a result of the Glenlivet Development Project will also be small, relative to the wider occurrence of similar habitats within the areas surveyed and across the west of Shetland continental shelf and slope. Given that potentially sensitive habitats and species known to be present in the wider area have not been recorded within the vicinity of Glenlivet Development Project and are thus not expected to be impacted, the overall residual consequence has been ranked as minor. Direct impacts on habitat will occur during the installation phase and the structures will be present for the life of the development, with recovery expected within less than 5 years of decommissioning; as a result, the residual impact of the direct impact on seabed habitats is considered not significant.

Indirect disturbance

In addition to the area of direct impact is the area likely to be influenced by potential sediment suspension and re-settlement of around activities causing seabed disturbance; this area is estimated to be approximately 1.66 km2. Re-settlement of sediment plumes as part of the Glenlivet Development Project will therefore be localised and only temporary in nature, occurring only during installation and drilling. It is reported that near-seabed concentrations of suspended particulate material on the west of Shetland continental slope are naturally high, meaning that benthic species in the vicinity of the Glenlivet Development Project are more likely to be tolerant to some extent of varying sediment levels in the water column.

The re-suspension of sediment will be temporary, restricted to the drilling and installation phases of the project, and will not occur during the operational phase. Within the vicinity of the Glenlivet Development Project, the sediments are relatively coarse in nature which means that plumes of re-suspended sediment will tend to re-settle quickly and will not be prolonged or affect large areas. Where sediment re-suspension does occur, the majority of species present, particularly the infaunal communities, are not expected to be significantly affected, and rapid recovery is expected. The residual consequence for this has therefore been ranked as minor. Indirect impacts on habitat will occur during the installation phase only. As a result, the residual impact of the indirect impact on seabed habitats is considered not significant.

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Faroe-Shetland Sponge Belt

As outlined in Section S.3, the Glenlivet Development Project is partially located within the Faroes Shetland Sponge Belt marine protected area, which is designated in part for benthic habitats, deep-sea sponge aggregations and ocean quahog (Arctica islandica) aggregations. No ocean quahogs were recorded in any of the surveys within the Glenlivet Development Project area. Sponges were however observed along the route between Glenlivet and Edradour and between Edradour and ILT3. However, based on the OSPAR definition of ‘deep-sea sponge aggregations’ and an application of this definition in recent work by the JNCC, the sponge communities observed in these areas are considered to be too small in area and of insufficient density to constitute an OSPAR ‘deep-sea sponge aggregation’ habitat. Furthermore, the isolated examples of possible hard corals observed during survey work in the Glenlivet field and at the ILT3 location are not considered to constitute cold water coral reef habitat.

Conclusion

The limited direct and indirect impact, the short-term nature of many of the impacts and the absence of habitats and species of key conservation interest mean that the Glenlivet Development Project will not have a significant impact on seabed habitats or species.

S.6 NOISE IMPACTS Noise is readily transmitted underwater and there is potential for the sound produced by oil and gas activities to cause detrimental effects to marine species (e.g. mammals and fish). The introduction of additional noise to the marine environment could potentially interfere with the ability of these animals to determine the presence of predators, food and underwater features and obstructions. Noise could cause physical damage within a short range of the source, or short-term behavioural changes at greater distances.

There are a number of activities planned as part of the Glenlivet Development Project which are likely to involve noise emissions of varying scale:

• Drilling;

• Vessel movements, including the possible use of a dynamically positioned drill rig; and

• Vertical seismic profiling (VSP) at two wells.

Noise propagation modelling has been undertaken as part of the EIA to predict possible injury and disturbance impact ranges. This modelling has shown that the risk of marine mammals sustaining physiological damage as a result of the vessels proposed for use is minimal. Cetaceans (whales and dolphins) would need to remain within a distance of less than 75 m and seals within 250 m of even the noisiest vessel for a period of 24 hours or more in order to exceed the relevant criteria. For moving vessels, the animal would have to follow the vessel to remain within the impact area. The noise modelling indicates that disturbance zones relating to vessel noise could extend out to between 1 and 15 km.

With regard to VSP during drilling, the potential injury zone for most cetaceans extends out to a radius of less than 10 m; for harbour porpoise this is limited to 410 m. The potential injury impact zone for seals is limited to 20 m. The likelihood of injury occurring will be further reduced by implementing a series of mitigation measures based on the JNCC ‘Guidelines for minimising the risk of disturbance and injury to marine mammals from seismic activity’, which includes a soft-start procedure and visual monitoring of a 500 m mitigation zone. These measures, outlined below, will result in the area of potential injury for marine mammals effectively being eliminated, since there should be no marine mammals within 500 m of the VSP at start up. The noise modelling for VSP indicates that disturbance zones could extend out to approximately 1 km.

Vessel sound sources are sufficiently low to mean that no lethality is expected and there is no requirement for additional mitigation measures. For VSP activities, TEP UK will deploy the measures described in the relevant JNCC guidelines, which include:

• Two qualified and experienced Marine Mammal Observers (MMO) being present for the duration of

the VSP operations to undertake cetacean visual monitoring during all daylight hours;

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• The use of passive acoustic monitoring (PAM) to detect any whales and dolphins that are vocalising

within close proximity to the operations;

• Airguns starting at a low energy, building up over a period of 20 minutes to full power, to give animals

time to move away; and

• Delaying starting of activities if cetaceans are observed or detected within 500 m of the noise sources

until 20 minutes after the last sighting.

To understand the residual impact on animals experiencing disturbance to normal behaviour, it is important to understand what proportion of the population might be affected. Temporarily affecting a small proportion of a population would be highly unlikely to result in population level impacts, and would not be considered significant. In contrast, affecting a large proportion may be considered significant. Considering the density of marine mammals in the area and the size of the populations to which they belong, no more than 0.003% of any species population will be affected by any of the operations described herein. It is therefore concluded that whilst a small number of individual animals may exhibit some form of change in behaviour for the period in which they encounter sound from the survey, this number is so small that it would be largely undetectable against natural variation and would have no residual impact at the population level. The small potential impact zones and short duration of activity mean that the noise emissions will not represent a barrier to wider, regional movements of marine mammals, such as those migrating between southern and northern latitudes in spring and autumn. Consequently, it is concluded that vessel use and VSP are unlikely to result in significant disturbance to marine mammals.

For fish species, potential impact zones from noisy activities are likely to be limited to tens or hundreds of metres; as such, it would be expected that few animals would be injured or disturbed and the vessels would not represent a barrier to movement of the migrating species known to use the area. Estimates of fish populations are generally not available but it is likely that many millions of individuals make up most species populations. The movement of fish tens or hundreds of metres away from a noise source out of the potential injury or disturbance impact zones would not constitute a large scale movement by individuals of a species and would be highly unlikely to result in population level impacts. Similarly, the potential impact of fish outside the area finding the noise levels too high to enter the area immediately around a noise source would be unlikely to result in population level impacts.

The limited impact zones and the short-term nature of almost all the noise sources mean that the Glenlivet Development Project will not have a significant impact on marine mammals or fish.

S.7 ATMOSPHERIC EMISSIONS Emissions are expected to arise from the following activities:

• Drilling and completion of two wells (including well testing);

• Vessels associated with the installation of pipelines and subsea infrastructure; and

• Vessels associated with commissioning and maintenance.

It is not anticipated that production resulting from the Glenlivet Development Project will result in a net increase of emissions at the SGP because overall production through the SGP will not increase and will remain within the current capacity of the plant.

The emissions produced from the installation and commissioning activities offshore have the potential to contribute to a variety of environmental effects ranging from localised reductions in air quality to consequences at a regional or global level such as ground level ozone production, climate change (greenhouse gases), acidification (acid rain) and damage to the ozone layer. Localised impacts may include elevated levels of atmospheric emissions in the immediate area of the vessels. In total, gases with a carbon dioxide equivalent (a standard unit for measuring carbon footprint) of approximately 87,000 tonnes are likely to be emitted through the Project life. The dispersive nature of the environment offshore and the lack of human receptors in the vicinity of the Glenlivet Development Project is such that locally elevated concentrations of combustion products will be short-lived and are unlikely to result in environmental impact.

In terms of contribution to cumulative effects at a regional or global level such as climate change and acidification, this might be assessed in terms of comparison with annual emissions from activities on the

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UKCS. The contribution to total annual UKCS emissions from combustion emissions as a result of drilling, well testing, subsea infrastructure installation and pipelay from the Glenlivet Development Project is estimated to amount to 0.12%. The release of greenhouse gases into the environment from the Glenlivet Development Project and their contribution to global warming will therefore be negligible or minor in relation to those from the wider offshore industry and outputs at a national or international level.

All vessels employed during drilling and installation activities will comply with relevant merchant shipping regulations which will ensure the levels of pollutants entering the atmosphere are minimised. All combustion equipment will be subject to regular monitoring and inspections to ensure an effective maintenance regime is in place, ensuring all combustion equipment runs as efficiently as possible. TEP UK will ensure that drilling and vessel operations are carefully planned to reduce vessel numbers and the duration of operations.

Although the Project will result in some emissions to the environment, the adoption of suitable mitigation measures and best practice approach, alongside the absence of any sensitive local receptors, means that the Glenlivet Development Project will not have a significant impact in terms of air quality and global climate change.

S.8 DISCHARGES TO SEA During drilling, installation and the operational phases of the Glenlivet Development Project, there will be a number of potential discharges to sea:

• Drilling discharges

o Mud and cuttings;

o Cement;

o Clean-up and completion chemicals; and

o Reservoir hydrocarbons within effluent from filtration package during well testing.

• Commissioning discharges

o Pipeline commissioning discharges.

• Operational discharges

o Produced water discharges at SGP; and

o Subsea control fluid discharges.

The top sections of the well will involve the deposition of cuttings and drilling mud onto the seabed. The remaining sections of the well will be drilled using a closed circulation system so that mud and cuttings will be returned to the rig for processing prior to the cuttings being discharged and the mud recycled for use. These overboard discharges will descend through the water column and be spread thinly over a wider area of seabed. On a precautionary basis, it is estimated that a total of 5,300 tonnes of mud and cuttings will be discharged during drilling operations at the two wells. It is estimated that a total of 4,000 tonnes of WBM cuttings will be discharged directly to the seabed and 1,300 tonnes of WBM cuttings will be returned to the drilling rig and discharged overboard following cleaning and recycling to the water column.

Cuttings dispersion modelling was undertaken for the Glenlivet exploration well, drilled in 2010, approximately 1 km west of the planned Glenlivet Development Project. Given the small distance between the wells and similar water depths, it is considered that this cuttings dispersion modelling could reasonably be considered representative of the Glenlivet Development Project. In addition, the drill mud type used for the exploration well is similar to that being planned for Glenlivet, and the overall quantities of mud and cuttings being discharged from each of the Glenlivet wells is slightly less than that modelled for the exploration well (thus the modelling conducted for the exploration well can be considered a conservative estimate of what will happen at each of the Glenlivet wells). The modelling predicted cuttings deposition in a 560 m by 120 m (0.85 km2) oval-shaped area aligned in a south-west to north-east direction (Figure S.9). The highest concentrations of cuttings (203 mm deposition thickness) are likely to be present at the discharge point. The thickness of cuttings deposited on the seabed was predicted to fall quickly to 5 mm within approximately 50 m of the well location and then to 1 mm or less over the remainder of the 0.85 km2 oval area. The majority of the mud remains suspended in the water column and does not settle.

The accumulation of these cuttings, drilling mud and cement at the drilling location is likely to change the benthic community in the immediate area by burying some animals and impairing the feeding and respiration

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of others. It is expected that the communities in the immediate vicinity of the wells will be lost, and that increased concentrations of suspended particles near the seabed may also impair respiratory and feeding processes, inducing metabolic stress and reducing growth and survival rates. The net result therefore is likely to be a reduction in species diversity and production and a change in the species composition of the community within approximately 50 m of the wellheads.

From survey work, none of the habitats, species or communities occurring around the well locations are likely to qualify as priority marine features or to represent features of conservation interest. The Glenlivet Development Project is partially located within the Faroes Shetland Sponge Belt Marine Protected Area which is designated in part for benthic habitats, deep-sea sponge aggregations and ocean quahog aggregations. No ocean quahogs were recorded in any of the surveys within the Glenlivet Development Project area. Based on the OSPAR definition of ‘deep-sea sponge aggregations’ and on an application of this definition in recent work by the JNCC, the sponge communities observed in the Glenlivet Development Project area are considered to be too small in area and of insufficient density to constitute an OSPAR ‘deep-sea sponge aggregation’ habitat. The limited discharge from drilling activities is not considered to be significant for the features of MPA.

Figure S.9 Modelling of seabed cuttings concentrations

Steel casings are installed into the well throughout the drilling operation to provide structural strength and to isolate unstable formations and different formation fluids. Each casing is cemented into place to form a seal between the casing and the formation; a small amount of cement from top-hole casings may be squeezed out onto the seabed around the well, along with the previously discharged cuttings and mud. During well clean-up and completion operations, the wells will be displaced to inhibited seawater and/or brine prior to any well testing. Chemicals used during well clean-up and completion operations will also be discharged to the water column.

Once final engineering details and chemical requirements are known, and prior to the commencement of any drilling operations, TEP UK will submit a Drilling Permit Application, supported by appropriate detailed chemical risk assessments. As part of the Drilling Permit Application process, TEP UK will target candidates for substitution to ensure that the chemicals chosen are fit for purpose but also have a low environmental hazard profile. Chemicals will only be used in accordance with the Drilling Permit Application conditions and

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according to TEP UK’s internal requirements. TEP UK is committed to reducing the environmental impacts of the chemicals used and discharged. Chemicals selection will consider health and safety, environmental, economic and technical factors.

Following installation and prior to commencement of production, testing and pre-commissioning activities will occur for the flowline. Water will be used to flood the flowline (either seawater or freshwater depending on what flowline material is chosen) and this may be treated with chemicals; these chemicals may include biocides, oxygen scavengers and corrosion inhibitors, required to maintain the integrity of the pipework during installation and prior to production, and tracer dyes used during installation operations to aid in leak detection. During dewatering of the pipeline, this treated water will be discharged offshore at either the ILT3 (380 m water depth) or Glenlivet end (435 m water depth) of the Glenlivet production flowline. This discharge into the water column will be rapidly diluted in the dispersive offshore environment. Chemicals will be selected to have minimal impact on the environment in accordance with TEP UK chemical selection procedure and in compliance with the UK offshore chemicals regulations, and will be subject to a detailed permit application at the time.

Glenlivet area hydrocarbons (gas and condensate) will be commingled with those from the Laggan, Tormore and Edradour fields before being processed together at the SGP. At the SGP, the produced water separated from the commingled fluids is treated before being discharged into Yell Sound. Produced water from the Glenlivet Development Project will therefore be managed within the design capacity of the existing SGP effluent water treatment system. The addition of produced water originating from the Glenlivet Development Project will not increase the effluent water discharge flowrate from that assessed under the Laggan-Tormore development and TEP UK will endeavour to make use of the same chemicals currently used in the Laggan-Tormore-Edradour Developments during the operational phase of the Glenlivet Development Project.

Although the Project will result in some discharges to the marine environment, the adoption of suitable mitigation measures and best practice approach, alongside the absence of any sensitive local receptors, means that the Glenlivet Development Project will not have a significant impact in terms of discharges to sea.

S.9 INTERACTIONS WITH OTHER SEA USERS There are two main mechanisms by which the Glenlivet Development Project could impact on other users of the marine environment (e.g. fishing, shipping):

• Impacts due to increased vessel presence during drilling and installation/commissioning phases,

leading to loss of access and increased collision risk; and

• Impacts due to the longer-term presence of seabed infrastructure and anchor mounds.

It is expected that vessels could be on site in the Glenlivet Development Project area between early 2015 and 2017. More vessels in the area means an increased risk of collision. In addition, whilst the drilling rig is on location at Glenlivet and during the installation of the flowline, umbilical and MEG and piggy-backed service line, a temporary 500 m radius exclusion zone will be in place around rig and vessels. Both increased collision risk and exclusion during installation would be temporary impacts.

In terms of longer-term impacts, TEP UK intends to apply for a 500 m safety zone to be permanently present around the Glenlivet drill centre. In addition, there is potential for the formation of anchor mounds due to the deployment of the drilling rig anchors. There is also the potential for berms of sediment to be created during trenching/ploughing activities to remove boulders from the pipeline route. Over-trawling by fishing vessels of such mounds and berms could result in sediment being retained in fishing nets, with potential damage to equipment, catch and to the safety of the fishing vessels and persons on board. It is also possible that fishing may be impacted by the physical presence of subsea infrastructure through the introduction of potential snagging points for fishing nets. Towed nets can become trapped on subsea equipment, resulting in loss of fishing gear or potentially posing a threat to the safety of the fishing vessel and the crew. Such snagging can occur where there are protrusions from subsea structure or where a gap exists beneath a structure.

To limit the potential for temporary or longer-term impact mechanisms to significantly affect other sea users, TEP UK intends to employ a number of industry standard and project-specific mitigation measures, including:

• A standby vessel will operate over the whole time that the drilling rig is in place;

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• A Collision Risk Assessment will be completed prior to installation operations, and a full review of

mitigation and management measures undertaken to ensure they are adequate;

• Reduction in vessel requirement and vessel days as far as practicable;

• On-going consultation with the Scottish Fishermen’s Federation (SFF);

• A TEP UK fisheries liaison officer will be engaged during pipeline and rock placement operations;

• Rig moves will be limited as far as is practicable to limit the number of anchor mounds that could

potentially form, and anchor plans will take into account the potential for re-use of previous anchoring

locations;

• TEP UK will review the extent to which berms are created by the trenching/ploughing activities and

consider whether remediation (potentially in the form of trawling beams across the berms to flatten

them down) will be necessary;

• All subsea structures will be designed to be overtrawlable, including the rock protection berms over

the production flowline, the MEG and piggy-backed service line and the umbilical;

• Subsea structures and rock protected pipelines and umbilicals will be charted as navigational

hazards; and

• Information on the location of subsea infrastructure will be communicated to other sea users through

the standard communication channels including Kingfisher and Notice to Mariners.

Although there will be an increase in the number of vessels in the area during drilling, completion, umbilical and pipelay and subsea infrastructure installation, these activities will only be of a relatively limited duration. A collision risk assessment will be carried out as part of the Glenlivet Development Project; however, in advance of that assessment being available, the collision risk assessment conducted at the Spinnaker well (within the nearby Edradour field) suggests the annual frequency of vessel collisions with a drilling rig at the Spinnaker well as 5.9 x 10-05, well below the historical average ship collision frequency for offshore installations in the UKCS. The Glenlivet Development Project is located in an area of generally low shipping activity and with the limited vessel requirement and mitigation measures to be deployed, there is little risk of an increase in the risk of vessel collision as a consequence of increased vessel activities.

Vessel use, and subsequent exclusion of other sea users, will occur only during the installation phase (and on maintenance occasions during the life of the field). The approximately 0.8 km2 total footprint of the permanent aspects of the development represents only a small fraction (0.005%) of the approximately 15,000 km2 of fishing area available to the west of Shetland. In addition, fishermen have been known to preferentially target pipelines due to the tendency for these structures to attract fish. Taking into account the localised and temporary nature of the access restrictions posed by the Glenlivet Development Project and the low level of vessel traffic, the overall risk of interference with fishing and shipping activity is considered to be low.

The pipelines for the Glenlivet Development Project will be protected with rock along their length and thus the risk of snagging along the pipeline will be significantly reduced. Moreover, subsea structures including the manifold and FLETs will be covered by an overtrawlable structure. These measures are standard across the industry and have previously assisted in reducing the impact of the oil and gas industry on other sea users. Anchor mounds and trench/plough berms are only likely to persist at the Glenlivet Development Project in the short to medium term. Due to the small number of anchor placements and the temporary nature of any resultant mounds, it is likely that the risks related to the Glenlivet Development Project are limited. Taking into account the fact that all subsea infrastructure including pipelines will be overtrawlable, and evidence of the effectiveness of charting and notification procedures with regard to awareness of obstructions by the fishing industry, the overall risk of snagging risk is considered to be low.

Although the Project will result in short-term increases in vessel traffic and structures will be present for the longer-term, the mitigation measures to reduce collision risk and the use of overtrawlable structures, including rock protection, mean that the Glenlivet Development Project will not have a significant impact on other sea users.

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S.10 ACCIDENTAL EVENTS All offshore oil and gas exploration, production and export operations carry with them some risk of accidental hydrocarbon or chemical spill. Potential sources include:

• Bunkering and cargo loading/handling (including mud handling) operations;

• Upsets in bilge treatment systems;

• Storage tank failures of lube oils, fuel oil, oil based muds, base oil and chemicals;

• Spill during maintenance activities including equipment removal and lubrication;

• Loss of well control during drilling;

• Damage sustained during a collision, grounding or fire;

• Overpressure rupture of pipelines;

• Corrosion of pipelines; and

• Structural failures of subsea equipment.

Most spills from the offshore oil and gas industry are small and most of the potential sources of impact could only result in small spills that would have very limited environmental impact. The main potential for larger releases comes from damage to pipelines or to wells.

Spill modelling for an uncontrolled well blowout of condensate predicted that there would be no beaching. This modelling, called deterministic modelling, predicts spill behaviour in a given wind direction to identify minimum (i.e. worst-case) beaching times under extreme weather conditions.

A second type of modelling, stochastic modelling, uses actual wind and tidal data collected over a period of time to establish a statistical picture of the probability of coastline pollution in different locations. This contributes to the locating of shoreline response resources, focusing resources on areas most probably affected in the unlikely event of oil beaching, rather than on areas where modelling indicates hydrocarbons will not beach. Beaching as a result of surface pollution may occur after 13 days and 11 hours on the north coast of Shetland, although the probability of beaching is low (up to 20%). The maximum probability of beaching is 61% on the west coast of Norway. This is shown in Figure S.10. The maximum mass of beached hydrocarbons occurring in any single stochastic simulation was approximately 197 tonnes. Note that this value includes both condensate in a visible surface sheen or slick and also hydrocarbons that have been dispersed as small invisible droplets through the water column.

Modelling was also conducted for a loss of diesel from the drilling rig. Deterministic modelling with a 30 knot onshore wind indicated up to approximately 0.1 tonnes may beach on Shetland, with first beaching occurring 1 day and 5 hours after release. Deterministic modelling with a 30 knot wind blowing towards the UK/Norway median line predicted diesel would not beach nor cross the boundary line. Stochastic modelling indicated the majority of the spilled diesel would be directed around the north of Shetland with only a small probability (10%) of diesel beaching. The maximum mass of diesel beaching on Shetland in any single stochastic simulation was 1,182 tonnes. As noted above for a condensate spill, this value includes both hydrocarbons in a visible surface sheen or slick and also those that have been dispersed as small invisible droplets through the water column.

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Figure S.10 Probability of condensate shore hits from surface pollution and water column contamination 134 days after the start of the release

In addition to the hydrocarbon spill risk, there is also the risk of a chemical spill from drilling activities and throughout the operational life of the Glenlivet Development Project. Chemical spills may occur during chemical transfer, chemical/mud handling, or through mechanical failure.

In terms of smaller spills, a series of measures will be in place:

• The rig will have a UK safety case and will be class certified by a recognised certifying authority.

TEP UK will perform assurance audits prior to rig acceptance to confirm all critical systems such as

subsea and surface blowout prevention equipment and drilling fluid circulating and processing

systems are fully certified and working as designed;

• The rig will comply with International Maritime Organisation/Maritime and Coastguard Agency (MCA)

codes for prevention of oil pollution, and will maintain an on-board Shipboard Oil Pollution Emergency

Plan (SOPEP);

• Approach procedures and poor weather operational restrictions for visiting vessels and transfer

operations at the drilling rig will be defined prior to operations;

• Regular maintenance and inspection of equipment and high spill risk areas (in particular bunkering

hoses, bunds, storage tank valves etc.) will take place; and

• Environmental spill kits, including absorbent material, will be available on board the rig and vessels to

allow clean-up of any deck spills or leaks.

In terms of preparedness for larger spills, TEP UK has a number of arrangements in place to ensure appropriate response to any such scenario. For example, TEP UK will have a Master Service Agreement with an appropriate service provider under which TEP UK will be able to source a subsea containment system which includes subsea Capping Assembly and Ancillary equipment, subsea dispersant injection system, and subsea debris clearing equipment as required. TEP UK is party to the Offshore Pollution Liability Association Ltd (OPOL) which is a voluntary oil pollution compensation scheme for third party costs and

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damages from offshore oil pollution incidents from exploration and production facilities. TEP UK is also a member of the Operators Co-Operative Emergency Services, the organisational framework under which oil and gas companies operating in the waters of the North Sea and adjacent waters of the north-west European continental shelf co-operate and share resources in the event of an emergency situation. Finally, subsea infrastructure and pipelines will be protected from dropped objects and fishing gear interactions and will have regular integrity inspections.

From the assessment conducted, the most probable spills are spills of less than 1 tonne. This volume is predicted to naturally disperse and break down rapidly in the environment through weathering without risk of beaching. Larger blowout and pipeline spills could reach the coastline, but are considered to be remote events, i.e. of very low probability. Even with comprehensive prevention measures in place, the residual risk of spill remains, and integral to offshore operations is the formulation of detailed and fully tested contingency response plans. As described above, TEP UK has in place a range of response/mitigation measures to address such risks. Given these measures and the low likelihood large releases, it is expected that the Glenlivet Development Project will not have a significant impact.

S.11 WASTE MANAGEMENT TEP UK has a ‘Duty of Care’ to ensure that it handles all of its controlled waste safely and in compliance with the appropriate regulations. This also includes organisations that collect, transport or receive TEP UK waste. Measures to be adopted are based on the recognised waste ‘hierarchy’ and include:

• Waste should be prevented or reduced at source as far as possible (e.g. waste is designed out or

packaging is reduced, the correct amount of materials are ordered);

• Where waste cannot be prevented, waste should be reused or refurbished and then reused as far as

possible;

• Waste materials should be recycled or reprocessed into a form that allows them to be reclaimed as a

secondary raw material; and

• Where useful secondary materials cannot be reclaimed, the energy content of waste should be

recovered and used as a substitute for non-renewable energy sources.

Glenlivet Development Project waste production will largely be generated during the drilling, installation and commissioning phases, both offshore and onshore. During the production phase, there will be little or no waste production.

To ensure optimum value from waste management activities, TEP UK will develop a Waste Management Plan in accordance with regulatory and corporate requirements. The plan will cover all stages of the Project lifecycle and will be developed before Project commencement. The plan will provide a structure for waste guidance and disposal, including maximising reuse and recycling, at all stages during the Project.

S.12 ENVIRONMENTAL MANAGEMENT TEP UK operates an Environmental Management System (EMS) certified to the relevant International Organization for Standardization standard (ISO 14001). The EMS (summarised in Figure S.11) provides a framework to ensure compliance with environmental legislation, the prevention of pollution and the achievement of continuous improvement of environmental performance. The EMS is continually under review in order to adapt to changing statutory requirements, corporate aspirations and new/evolving scientific knowledge and techniques.

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Figure S.11 TEP UK EMS framework

A Commitments Log has been developed for each aspect of the Glenlivet Development Project. This log summarises all mitigation and management measures identified during the EIA process, including where appropriate the requirement to undertake further environmental assessment during the on-going design process. The Commitments Log will be integrated into an Environmental Management Plan for the Project and will evolve and be updated as each element of the Project continues into the execution and subsequent operational phases. Monitoring of performance will be on-going through the life of the Project.

Commitments, objectives and targets set for the Glenlivet Development Project will be communicated within invitation to tender documentation and will form part of the contractual conditions. Contractors will therefore be aware of these from the very start of operations. Contractor performance will be monitored on an ongoing basis, environmental awareness presentations will be included in contractor induction sessions and a TEP UK representative will be on-board the drilling rig and key installation vessels during drilling and installation phases to ensure that environmental commitments and aspirations are met.

S.13 CONCLUSIONS Based on the findings of this EIA and the identification and subsequent application of the mitigation measures identified for each potentially significant environmental impact, it is concluded that the Glenlivet Development Project will not result in any significant environmental impacts.

The carrying forward of the findings and recommendations of this EIA through formal commitments will provide a transparent and auditable means of ensuring the measures identified will be delivered through TEP UK’s management system.

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