Water Tank and Soil Sampling Report

Woodvale

Prepared for:

Department of Environmental, Land Water and Planning Level 10, 8 Nicholson Street

East Melbourne Vic 3002

Distribution

Water Tank and Soil Sampling Report Woodvale

12 August 2015

Copies

Recipient

Copies

Recipient

1 electronic copy

Martin Robinson

Department of Environmental, Land, Water and Planning

Level 10, 8 Nicholson Street East Melbourne Vic 3006

1 PDF

Senversa Project File

1 Reliance - This document has been prepared solely for the use of DELWP No responsibility or liability to any third party is accepted for any damages arising out of the use of this document by any third party.

2 Copyright and Intellectual Property No portion of this document may be removed, extracted, copied, electronically stored or disseminated in any form without the prior written permission of Senversa. Intellectual property in relation to the methodology undertaken during the creation of this document remains the property of Senversa.

3 Technical Limitations and Assumptions - This document is issued subject to the technical limitations and assumptions provided in Section 10.

4 Confidentiality This report was prepared for DELWP and may contain confidential information. If you receive this report in error, please contact Senversa and we will arrange collection of this document.

Senversa Pty. Ltd.

ABN: 89 132 231 380

Ground Floor, 51 Clarke Street, Southbank Vic 3006 tel: + 61 3 9606 0070; fax: + 61 3 9606 0074

www.senversa.com.au

Primary Author

Project Manager

Belle Casement

Senior Environmental Scientist

Belle Casement

Senior Environmental Scientist

Project Director

Technical

Peer Review

Victoria Lazenby

Senior Associate

Michael Charge

Principal

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Distribution

Contents

List of Acronymsiv1.0Introduction1Project Background1Objectives1Scope of Work Undertaken12.0Background Information3Investigation Area Details3Environmental Setting3Topography, Drainage and Nearest Surface Water Body3Regional Geology3Regional Hydrogeology4Potential Contaminants of Concern43.0Regulatory Framework for Assessment5Soil5Regulatory Framework5Protected Beneficial Uses of Land5Soil Quality Objectives5Water6Regulatory Framework6Protected Beneficial Uses of Water73.2.1Tank Water Quality Objectives74.0Investigation Methodology8Standards and Guidance Documents8Investigation Strategy8Additional Works9Investigation Program9Water Quality Parameters10Laboratory Analysis10Quality Assurance / Quality Control115.0Water Results12Water Quality Parameters12Tank Water Laboratory Results12Arsenic13Antimony13Cadmium14Lead14Manganese15Zinc15Summary of Exceedences16m11135_009_rtp_rev3ii

Contents

5.1 Comparison with New Moon Discharge Water17

5.2 Directional and Distance Data Breakdown17

6.0Soil and Sediment Results18

6.1 Site Specific Geology18

6.2 Field Observations18

6.3 Soil Laboratory Results18

6.3.1 Maintenance of Modified Ecosystems18

6.3.2 Human Health19

6.4 Comparison with WEPC Sediment Samples19

6.5 Directional and Distance Data Breakdown20

7.0Data Trends21

8.0Conclusions23

9.0Limitations and Uncertainty24

9.1 Inherent Uncertainties and Limitations24

9.2 Project Specific Uncertainties25

10.0References26

Figures

Figure 1: Site Area Plan

Figure 2: Sample Location Plan Figure 3: Directional Data Breakdown Figure 4: Distance Data Breakdown

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Tables

Table 1: Water Quality Parameters

Table 2: Questionnaire Response Summaries Table 3: Analytical Tank Water Results

Table 4: Statistical Summary of Water Results

Table 5: Analytical Soil Results Standard Maintenance of Ecosystems Criteria

Table 6: Analytical Soil Results Ecological Significant Maintenance of Ecosystems Criteria Table 7: Statistical Summary of Surface Soil and Pond Sediment Results

Table 8a: Soil - Directional Data Summary Table 8b: Soil - Distance Data Summary

Table 8c: Tank Water - Directional Data Summary Table 8d: Tank Water - Distance Data Summary

Appendix A: Site Lithology Summaries Appendix B: Equipment Calibration Certificates Appendix C: Laboratory Certificates of Analysis Appendix D: Quality Assurance / Quality Control

List of Acronyms

Acronym

Description

ABC

Ambient background concentrations

ACL

And added contaminant limits

AHD

Australian Height Datum

ALS

Australian Laboratory Services Pty. Ltd.

ANZECC

Australia and New Zealand Environment Conservation Council

bgl

Below ground level

CoC

Chain of custody

CoPC

Chemical of potential concern

DELWP

Department of Environment, Land and Planning

DHHS

Department of Health and Human Service

DCNR

Department of Conservation and Natural Resources

DO

Dissolved oxygen

DQOs

Data quality objectives

EC

Electrical Conductivity

EIL

Ecologically-based Investigation Level

ESA

Environmental site assessment

EPA

Victorian Environment Protection Authority

Eurofins

Eurofins Pty Ltd | Mgt

GPS

Global positioning system

HASP

Health and Safety Plan

HIL

Health-based investigation level

LNAPL

Light non aqueous phase liquid

LOR

Limit of reporting

LTV

Long term trigger value

m AHD

Metres above Australian Height Datum

m bgl

Metres below ground level

m bTOC

Metres below top of casing

MGA

Map Grid Australia

MoE

Maintenance of Ecosystems

List of Acronyms

Acronym

Description

NATA

National Association of Testing Authorities

NEPC

National Environment Protection Council

NEPM

National Environment Protection Measure

PMCL

Prevention and Management of Contamination of Land

QA/QC

Quality analysis / quality control

RFQ

Request for quote

RSLs

Regional Screening Levels - USEPA

SAP

Sampling and analysis plan

SEPP

State Environment Protection Policy

STV

Short term trigger value

TDS

Total dissolved solids

WEPC

Woodvale Evaporation Pond Complex

WoV

Waters of Victoria

1.0Introduction

Senversa Pty Ltd was engaged by the Department of Environment, Land, Water and Planning (DELWP) to undertake a baseline metals investigation of domestic tank water and soils in the area surrounding the Woodvale Evaporation Pond Complex (WEPC). The WEPC is located approximately 10 km north of Bendigo.

Figure 1 depicts the WEPC area and the surrounding area.

1.1 Project Background

The WEPC is a purpose built water management facility, which forms part of the gold mining operations in the Bendigo region. Groundwater containing naturally occurring salts and metals is pumped to the site to evaporate as a part of mine dewatering.

With active mining in the region coming to an end, DELWP is coordinating the development of options for the management of groundwater in mine voids beneath Bendigo. As part of this broader study by DELWP, and in response to community concerns about the WEPC, DELWP commissioned the sampling and analysis of water samples from domestic rainwater tanks and surface soils in the vicinity of the WEPC. The community concerns were raised over the potential for the ponds to dry out, with dust from the ponds potentially carried by the wind, deposited onto nearby land (including roofs), and entering nearby rainwater tanks used for drinking water purposes.

1.2 Objectives

The objective of this assessment was to carry out a baseline investigation, assessing if off-site migration of sediments sourced from the WEPC has resulted in elevated concentrations of metals in domestic rainwater tank water and in surface soils in the vicinity of the ponds.

The scope of works was to:

Assess the concentrations of metals in primary domestic rainwater tanks used for drinking water supply in the vicinity of the WEPC.

Establish the current baseline conditions of metal concentrations in surface soils in the vicinity of the WEPC.

Domestic rainwater tanks were considered to be those tanks currently or regularly supplying drinking water for the property.

1.3 Scope of Work Undertaken

The scope of work undertaken was in part specified in the request for quotation (from DELWP, 25 March 2015), and further detailed in the Senversa proposal response dated 7 April 2015. The Sampling and Analysis Plan (SAP), 17 June 2015, (Senversa, 2015) was also prepared prior to conducting field-based investigation works. In summary, the investigation scope included:

Preparation of the SAP, including approximation of the number of domestic rainwater tanks within 1,000m of the WEPC, development of a soil sampling regime and development of analytical schedules for both soil and water samples.

Collection of samples from domestic rain water tanks within the sampling area. A total of 53 samples were collected from around the ponds.

Introduction

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Collection of a background domestic tank wa