INFORMATION REGARDING ENVIRONMENTAL AUDIT REPORTS

August 2007

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1 of 23 , ', Golder Associaies Pty Ltd A.C.N. 006 107 857 OFFICE ',

25 Burwood Road, Hadhorn, Vic 31 22 (POBox 6079, Hawthorn West, Vic 31 22 Australia] Telephone (031 981 9 4044 FOX (03) 981 8 7990 REPORT ON CeIehmting 25 years of Commifmenf to €ngineer-ing €xcellence

ENVIRONMENTAL AUDIT REPORT LOT 7 STENSON ROAD, KEALBA FOR BURGUNDY BRIDGE PTY LTD

Submitted to:

Environmental Protection Authority 477 Collins Street Melbourne, Victoria, 3000

DISTRIBUTION

1 COPY Environment Protection Authority 2 Copies Burgundy Bridge Pty Ltd 2 Copies Golder Associates Pty Ltd

October, 1997 97613590104 43s OFFICES IN ADELAIDE, BRISBANE, CAIRNS, GOLD COAST, MAROOCHYDORE, MELBOURNE, PERTH, SYDNEY, WOLLONGONG, JAKARTA h&&!&2 of 23 ASSOCIATED COMPANIES IN CANADA, FIJI, FINLAND, GERMANY, HONG KONG, HUNGARY, ITALY, SWEDEN, UNITED KINGDOM. UNITED STATES SYSTEM October. 1997 -1- 976 13590104

TABLE OF CONTENTS

SECTION PAGE

1. INTRODUCTION ...... 1 1.1 Purpose ofthe Rep0rt ...... 1 1.2 Site Description ...... 1 2 . SITE FEATURES ...... 4 . 2.1 Site History ...... >...... 4 2.2 Geology and Hydrogeology ...... 4 2.3 Chemicals of Interest ...... 5 3 . BENEFICIAL USE OF THE SITE ...... 5 4 . SITE CONDITIONS ...... 7 4.1 Assessment of Site Conditions...... 7 4.2 Remediation and Validation Works ...... 8 4.3 Final Site Conditions ...... 9 4.4 Quality of Data ...... 10 4.4.1 Site Assessment QNQC ...... 10 4.4.2 Sampling Density ...... 11 5 . HUMAN AND ENVIRONMENTAL RECEPTORS OF INTEREST ...... 11 5.1 Human Receptors ...... 11 5.2 Ecological Receptors ...... 11 6 . EXPOSURE TO CONTAMINANTS...... 12 6.1 Exposure Concentrations ...... 12 6.1.1 Surface Soils ...... 12 6.1.2 Sub-surface Soils...... 12 6.2 Human Exposure ...... 12 6.3 Screening Criteria ...... 13 .. 6.3.1 Average Screening Cntena ...... 13 6.3.2 ‘Hotspot’ Screening Criteria ...... 13 6.3.3 Ecological Exposure ...... 14 7 . RISK EVALUATION ...... 14 7.1 Exposure to Contaminated Soils ...... 14 7.2 Environmental Risk ...... 14 8 . ADEQUACY OF INFORMATION ...... :...... 15 9 . CONCLUSIONS...... 15 10. LIMITATIONS ...... 17 1 1. REFERENCES ...... 18

LIST OF FIGURES

Figure 1 .Locality Plan Figure 2a .Sampling Point Map .Phase 1 Figure 2b .Sampling Point Map .Phase 2 Figure 3 .Proposed Sub-Division Design Plan

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LIST OF APPENDICES

Appendix A - Letter dated 13 May, 1997 (Ref. No. 971789), MacGregor Soil Engineering Pty Ltd. Draft Site Investigation Report Re: Contamination Assessment Lot 7, Stenson Road, Kealba. Prepared for Masterplan Builders Pty Ltd by MacGregor Soil Engineering Pty Ltd. Letter dated 16 June, 1997 (Ref. No. 971789.04), MacGregor Soil Engineering Pty Ltd. Facsimile dated 3 1 July, 1997, MacGregor Soil Engineering Pty Ltd. Letter dated 5 August, 1997 (Ref. No. 971789/2), MacGregor Soil Engineering Pty Ltd. Site Investigation Report Re: Contamination Assessment Lot 7, Stenson Road, Kealba. Prepared for Masterplan Builders Pty Ltd by MacGregor Soil Engineering Pty Ltd. Title Documents

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1. INTRODUCTION

This report has been prepared by Mr Nick Withers (an accredited Environmental Auditor), of Golder Associates Pty Ltd, at the request of Mr Nick Polites of Burgundy Bridge Pty Ltd and relates to an audit of the site known as Lot 7 Stenson Road, Kealba, (Figure l), herein referred to as "the site". The approach undertaken for this audit complies with requirements of Section 57AA of the Environmental Protection Act (Victoria) and the EPA 'Guidelines for Environmental Auditors, Contaminated Land, Issue of Certificates of Environmental Audit', WM 91/14, May 1992 (Reference 1).

1.1 Purpose of the Report

The property is currently owned by Burgundy Bridge Pty Ltd, who plan to sell the site for redevelopment as residential land. Burgundy Bridge Pty Ltd have elected to undertake an Environmental Audit under Section 57AA of the Environment Protection Act, 1970. The purpose of this audit is to evaluate whether or not the site is suitable for any beneficial use and if not, whether it is suitable for the intended residential use. Thus, the audit will assess the health and environmental risks from exposure to any contaminated soil found at or from this site with respect to its potential beneficial uses.

1.2 Site Description

The site comprises that land described in Certificate of Title 1743, Folio 598, known as Crown Allotment 7 Section A, Parish of Maribymong, County of Bourke. The site is located along the southern edge of Stenson Road, Kealba, which is situated about 15 kilometres west of Melbourne (Figure 1). The site covers an area of approximately 7 Ha and is currently zoned as residential.

The site as a whole slopes gently to the south, towards a gully housing a small tributary of the Maribymong River. The bulk of the site is grassed and dotted with sporadic scrub vegetation.

Surrounding land to the north over Stenson Road and to the west is utilised for low density housing, while that to the east and south-east over the Maribymong River comprises undeveloped Melbourne Parks and Waterways land. An active quarry is located to the south of the site.

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TABLE 1 - AUDIT INFORMATION

Name of Audito Mr Nick Withers, Golder Associates Pty Ltd February 1998 Mr Nick Polites of Burgundy Bridge Pty Ltd 22 May, 1997 27 May, 1997 Lot 7 Stenson Road, Kealba City of Keilor % (3 ,, ,--5 Certificate of Title: Vol. 1743, Folio 598 Residential Burgundy Bridge Pty Ltd Currently Vacant

Reviewed: 1. Letter dated 13 May, 1997 (Ref. No. 971789), MacGregor Soil Engineering Pty Ltd. 2. Draft Site Investigation Report Re: Contamination Assessment Lot 7, Stenson Road, Kealba. Prepared for Masterplan Builders Pty Ltd by MacGregor Soil Engineering Pty Ltd. 3. Letter dated 16 June, 1997 (Ref. No. 971789.04), MacGregor Soil Engineering Pty Ltd. 4. Facsimile dated 31 July, 1997, MacGregor Soil Engineering Pty Ltd. 5. Letter dated 5 August, 1997 (Ref. No. 97 1789/2), MacGregor Soil Engineering Pty Ltd. 6. Site Investigation Report Re: Contamination Assessment Lot 7, Stenson Road, Kealba. Prepared for Masterplan Builders Pty Ltd by MacGregor Soil Engineering Pty Ltd.

These documents relate to the environmental assessment carried out at the site. and are provided in Appendix A ofthis repori. Other relevant information extracted from the above documents are cited when included in this text.

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2. SITE FEATURES

2.1 Site History

The site history was interpreted from the Environmental Site Assessment Report compiled by MacGregor Soil Engineering Pty Ltd which sourced relevant information from the present owners of the site and available aerial photographs. The Auditor verified the historical information as far as possible by an independent review of the aerial photographs and a Certificate of Title search for the property.

The Stenson Road property appears to have been undeveloped until the current time, though the Certificate of Title suggests that the land was first purchased in the late 1800s. Sands and McDougal Directory list no records of the property up to 1975, confirming that the site was undeveloped up to this time. Discussions with the client suggest that no other site uses other than possible grazing have been undertaken at the property. Aerial photographic evidence supports this history, with no development at the site visible until the present day.

Portions of the site were once used as a dumping ground for miscellaneous rubbish and general building debris. A site visit during the audit identified car bodies, corrugated iron sheeting, carpets, wood, soil and asbestos-cement (AC) sheeting in the surface soil of the northern portions of the property. These materials were removed at the Auditor’s request and the underlying areas validated during the audit.

2.2 Geology and Hydrogeology

The geology at the site has been determined from the Geological Survey of Victoria 1:63,360 scale Melbourne Sheet. The site is underlain by Quaternary deposits of the Newer Volcanics, which comprise basalt, scoria and basaltic clay. Soils developed on this bedrock typically comprise clay and sandy clays.

The site assessment confirmed expected geological conditions, with natural soils comprising clayey silt topsoil overlying stiff to very stiff, natural basaltic clay. Weathered basaltic bedrock or basalt floaters were encountered at between 0.6 and 1.2 metres depth. No fill was encountered on the site.

Groundwater was not encountered during the investigation. A review of the Victorian Groundwater database for groundwater bores within a 1 kilometre radius of the site

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~~ elucidated no useful information on the regional groundwater table. Groundwater is inferred to flow towards the nearby .

2.3 Chemicals of Interest

The site history and surface soil conditions suggest that the list of major chemicals of interest (ie. those which may have contaminated the site) should include:

Metals (including arsenic, lead, zinc, copper, chromium, nickel, and cadmium), associated with the identified metallic debris and the possible use of metal-based chemicals at the site;

Polycyclic Aromatic Hydrocarbons (PAHs) associated with the dumping of debris possibly containing lubricant or fuel materials and the possible dumping of ash material;

Total Petroleum Hydrocarbons (TPHs) associated with the dumping of debris possibly containing lubricant or fuel materials;

Organochlorine Pesticides (OCPs) associated with weed and vermin control, as part of the possible agricultural uses of the site.

Asbestos from broken AC sheeting.

3. BENEFICIAL USE OF THE SITE

The issue of a Certificate of Audit requires the Auditor to be satisfied that the chemical condition of the land at the site is neither detrimental nor potentially detrimental to any beneficial use of the land. In determining the condition of the site, the following beneficial uses of the land were considered:

the life, health and well-being of humans both on the site and external to the site;

the life, health and well-being of other forms of life, including most types of flora and fauna, both on and external to the site;

impact on groundwater.

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4. SITE CONDITIONS

4.1 Assessment of Site Conditions

4.1.1 Phase 1 - Investigation

An environmental assessment of the site condition was conducted by MacGregor Soil Engineering Pty Ltd (Australia) Pty Ltd and was presented in their draft report dated May 1997 (Reference 2). The assessment involved undertaking a site history evaluation of the property, collecting samples for laboratory analysis and reviewing the analytical data obtained.

The sampling program involved collection of samples from 36 points, each located within one of the 36 house blocks defined at the site, as shown in Figure 2. Single samples were collected from each locality and comprised a surface sample (0-2OOmm depth). The samples were laboratory composited into 9 groups of four for analysis as shown in Table 1.

The samples were analysed at MGT Environmental Consulting Pty Ltd (MGT), who are NATA accredited laboratory for all analyses conducted. All samples were transported to MGT under a Chain of Custody system and were analysed according to the analytical schedule shown in Table 1.

The analytical results of the environmental site assessment are presented as an attachment to the MacGregor Soil Engineering report. The analytical data across the site were below relevant criteria and were consistent with the known site history and the presence of in situ, natural soil at the property. Specifically, the data showed the following:

Organochlorine pesticides (OCPs), chlorinated hydrocarbons (CHCs), BTEX (benzene, toluene, ethyl benzene and xylene), polychlorinated biphenyls (PCBs), total phenols, cresols, total petroleum hydrocarbons (TPHs) and polycyclic aromatic hydrocarbons (PAHs) were below detection limits in all the samples analysed;

Heavy metals were reported at below EPA Clean Fill criteria and most were also below ANZECC Investigation Guidelines in all the samples analysed from the site;

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TABLE 1 - COMPOSITING AND ANALYTICAL SCHEDULE

Samples Composite Analytical Schedule Group BHI ,BH2, COMPI pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH3, BH4 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BHI only) BHS, BH6, COMP2 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH7, BH8 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BHS only) BH9, BHIO, COMP3 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BHI 1, BH12 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH9 only) BH13, BH14, COMP4 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BHIS, BH16 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH13 only) BH17, BH18, COMPS pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH 19, BH20 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH17 only) BH21, BH22, COMP6 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH23, BH24 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH21 only) BH25, BH26, COMP7 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH27, BH28 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH25 only) BH29, BH30, COMP8 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH3 1, BH32 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH29 only) BH33, BH34, COMP9 pH, As, Sb, Be, Cd, Cr, Co, Cu, Hg, Ni, Zn, Pb, Mo, Se, Sn, PAHs, PCBs, BH35, BH36 OCPs, total phenols, cresols, TPHs, CHCs, BTEX (BH33 only)

4.2 Phase 2 - Remediation and Validation Works

Limited remedial works were undertaken at the site in June-July 1997 by MacGregor Soil Engineering at the request of the Auditor and involved removal of the identified asbestos and other surface debris. An inspection by the Auditor’s representative in July 1997 confirmed that these works had been carried out to the Auditor’s satisfaction.

Fourteen surface validation samples were then collected from the remediated areas, as shown in Figure 2. Additionally, four sub-surface composite samples (C1 to C4) were collected from around 0.5 metre depth from the natural clays at the site. These samples were all analysed for heavy metals, PAHs and TPHs at MGT Environmental Consulting Pty Ltd.

The analytical results were reported at below ANZECC Investigation Guidelines and EPA Fill Material criteria for all analytes.

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4.3 Final Site Conditions

The final chemical condition of the site was assessed by statistical analysis of the investigation and validation data obtained by MacGregor Soil Engineering Pty Ltd. The average concentrations and 95% UCL average concentrations of potential contaminants at the site have been calculated and are provided in Table 2 below. The data used represent only samples of soil remaining on the site.

The analytical results provided have been compared with EPA Fill Material criteria, as listed in EPA Information Bulletin 448, Classification of Wastes (Reference 3) and ANZECCMMRC Investigation Guidelines, as listed in the Australian and New Zealand Guidelines for the Assessment and Management of Contaminated Sites, January 1992 (Reference 4). The raw data and the calculated statistical data have been compared directly with these assessment criteria, in order to evaluate the average analyte concentrations over the specific areas of the site covered by the composite groups and the individual samples. The soil sampled represented natural in situ material and the site history indicates only possible agricultural uses such as grazing.

A statistical summary of the relevant data is provided in Table 2 below.

TABLE 2 - SUMMARY AND STATISTICAL ANALYSIS OF SITE ANALYTICAL DATA (mg/kg)

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Five chromium concentrations slightly exceeding the ANZECCMHMRC Investigation Guidelines were detected in individual samples from across the site. These concentrations are believed to be natural and are consistent with reported chromium concentrations in soils derived from Newer Volcanics basalt.

The average and 95% UCL on the average concentrations of all analytes are below both EPA Clean Fill and ANZECC/NHMRC Investigation Guidelines, as shown in Table 2.

4.4 Quality of Data

Samples obtained by MacGregor Soil Engineering Pty Ltd during the site assessment and validation programs were submitted to MGT Environmental Consulting Pty Ltd (MGT) for analysis. MGT are accredited with the National Association of Testing Authorities (NATA) for the analytical methods used.

4.4.1 Site Assessment QNQC

The internal laboratory quality assurance results reported were consistent and within acceptable limits. MGT reported spike percentage recoveries ranging between 84% and 103% in the 22 total spikes undertaken. Relative percentile differences (RPDs) for internal duplicate analyses were all within the acceptable range off 20%-50%. Blank analyses were all below detection limits for all analytes.

Overall, the results indicated good internal laboratory quality control. However, no field duplicates were collected or submitted for analysis by MacGregor Soil Engineering Pty Ltd during the site assessment or validation sampling. This lack of check testing is non-standard and is usually cause for corrective action. Therefore, the Auditor has reviewed the variances within the raw data and the statistical summaries in the light of the site inspection, the site history and the natural soil profile present, in order to assess the need for and the scope of such corrective action. After careful consideration, he decided that additional check tests would not be warranted because the results would be very unlikely to materially affect his conclusion about the overall site conditions. The Auditor has concluded that the data provided is of sufficient quality and accuracy to form a reliable judgement of the status of the site.

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4.4.2 Sampling Density

The site assessment and validation programs utilised the results of sampling fiom a total of 50 locations across the site. The approximate sampling density across the site is therefore 1 sample location per 1,400 m2. This density and the spread of sample locations undertaken in the MacGregor Soil Engineering assessment are considered satisfactory to obtain a judgement of the contamination status of the site, given the chemical data obtained, the known site history and the existing natural soil profile.

5. HUMAN AND ENVIRONMENTAL RECEPTORS OF INTEREST

We understand that much of this property is to be developed as low density residential land, as outlined in the proposed plan of sub-division (Figure 4). In order to consider a site as suitable for development, we need to firstly consider any beneficial use that may be made of that site.

5.1 Human Receptors

Given the intended development of the site the categories of people who might be exposed to the soils at this site could include:

0 adult or child residents, visitorsftrespassers exposed to surface soils;

utility or construction workers involved in excavations at the site, either associated with developing the ultimate site end use or at subsequent times; and

adult or child residents consuming home grown produce.

Residential scenario-based exposures provide the highest risk (which results in the lowest acceptance criteria). A child resident is the most sensitive receptor, and therefore criteria protective of children will also protect other categories of people listed above.

5.2 Ecological Receptors

The primary ecological receptors of interest at this site would be soil fauna including earthworms and larval forms of fauna that develop in surface soils and sediment in stormwater drainage pathways on or emanating from this site and flora which have their roots in or uptake nutrients and minerals from the surface soils. Also of interest is the

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6. EXPOSURE TO CONTAMINANTS

6.1 Exposure Concentrations

6.1.1 Surface Soils

From a risk assessment perspective for this site, exposure concentrations for surface soils have been taken as the 95% UCL concentrations within the surface natural soils in a domain of interest. The relevant domain of interest is typically taken as a single residential house block of approximate area 500 m2. The 95% UCL concentrations and maximum individual sample concentrations within the domain must be such that the likely exposure concentrations within the domains are below acceptable levels for the proposed land use.

Given the presence of natural soil at the site and the pattern of past uses, it is conservative (ie. safe) to assume that the 95% UCL concentration in any single 500 m2 domain is the same as the 95% UCL concentration over the site as a whole. These concentrations are given in Table 2. For the purposes of considering hotspots (see Section 6.3.2), the maximum values in Table 2 have been multiplied by 4 (the number of sub-samples in each composite analysis) to give a pessimistic estimate of maximum individual sample concentrations.

6.1.2 Sub-surface Soils

The concentrations in sub-surface soils are likely to be lower than those in the surface soils, based on the pattern of past site uses. However, for the purposes of this report, the exposure concentrations for sub-surface soils are taken to be equal to those in the surface soils.

6.2 Human Exposure

Screening criteria for surface soils have been derived using exposure durations and associated risks that would be consistent with residential use. Screening criteria for residential use which are protective of child and adult residents will also protect the other categories of human receptor listed above.

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6.3 Screening Criteria

6.3.1 Average Screening Criteria

The potential contaminant concentrations outlined in Section 3 are compared below to screening criteria derived from EPA Fill Material guidelines (Reference 2). These screening criteria are provided in Table 3 below. Based on our previous experience, a formal risk evaluation for a residential property scenario would tend to generate screening criteria in the same order or greater as those given in Table 3.

TABLE 3 - SCREENING CRITERIA FOR SOILS

ANALYTE Average Screening Criteria Hotspot Screening (mg/kg) Criteria (mgkg) Total PAHs 20 100 Benzo-a-pyrene I 1 I 5 Total BTEX 7 35 Benzene 1 5 TPHs (

6.3.2 ‘Hotspot’ Screening Criteria

‘Hotspot’ screening criteria are designed to ensure that, as far as possible, isolated pockets of contamination do not remain even when average screening criteria are fulfilled. The criteria represent the maximum individual sample concentrations which can be accommodated within a domain, assuming a given land use. For the purposes of this document these criteria are 5 times the average screening criteria for the particular chemicavmedidreceptor of interest.

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~

6.3.3 Ecological Exposure

The criteria adopted by Golder Associates are also designed to protect plants and fauna such as earthworms, and also limit the potential for leaching of contaminants fiom ;he site.

7. RISK EVALUATION

$\ This section discusses the risk to human health and the environment associated with exposure concentrations of contaminants which remain on the site. As such, details of the proposed development need to be taken into consideration when evaluating the future potential risks to receptors.

7.1 Exposure to Contaminated Soils

The concentrations of chemicals of concern remaining at this site have been discussed in Section 4 of this audit report. In summary, the exposure concentrations and estimated maximum individual sample concentrations of potential contaminants across the site are below the relevant screening criteria. Additionally, the remedial works conducted to remove minor rubbish are considered to have been satisfactorily completed for the purposes of this audit.

The generally low analyte concentrations detected across the site are consistent with the reported site history and the exposure across the site of in situ, natural soils. The human health risks associated with the residual chemicals in the natural soils at this site are therefore acceptable, particularly given the plan of development detailed in Figure 3 of this report.

7.2 Environmental Risk

The screening criteria given in Section 6.3.1 also protect the ecological receptors of interest as well as human health. Given that the chemical concentrations identified are generally well below the screening/acceptance criteria, the potential for impacts upon ecological receptors and associated environmental risks are acceptably low.

8. ADEQUACY OF INFORMATION

A review of information supplied by MacGregor Soil Engineering Pty Ltd, as outlined in the previous sections of this report are considered adequate to meet the requirements of a Statutory Audit. These sources of information and the Auditor’s verification data include:

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Historical data, indicating previous use of the site.

Distribution and frequency of sampling locations to obtain a valued judgement of the contamination status of the site.

An analytical suite sufficient to identify a broad spectrum of likely contaminants and the use of NATA accredited laboratories for accurate, quality analyses.

Soil contamination sampling procedures suitable to produce accurate results.

The Auditor has noted that no field duplicates were collected or submitted for analysis by MacGregor Soil Engineering Pty Ltd during the site sampling programs. This lack of check testing is non-standard and is usually cause for corrective action. However, the Auditor has reviewed the variances within the raw data and the statistical summaries in the light of the site information obtained during the audit process. After careful consideration, he decided that additional check tests would not be warranted because the results would be very unlikely to materially affect his conclusion about the suitability of the site for its proposed use.

9. CONCLUSIONS

Assessment of the Stenson Road property, Kealba indicated that the soil at the site met both EPA Fill Material and ANZECCiNHMRC criteria. Scattered rubbish and metallic debris were noted at various locations across the site. Remediation involved excavation of unacceptable soils and debris and off-site disposal of such materials. The remediated areas were then validated.

The final condition of the site indicates that the concentrations of contaminants remaining in the soil are below the Auditor’s screening criteria. This produces confidence that the current condition of the site poses acceptable risk to potential human and ecological receptors given the proposed plan of development as low density residential use of the site.

A Certificate of Environmental Audit is therefore issued for the site pertaining to the final condition of the site at the conclusion of the validation works.

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10. LIMITATIONS

This report represents a review of information relating to site located at Stenson Road, Kealba (as shown in Figure I), that was obtained from the sources and contacts noted by methods described in this report. While Golder Associates has used reasonable care to avoid . reliance upon data and information that is inaccurate, Golder Associates was not able to verify the accuracy or completeness of all data and information available to Golder Associates. Our conclusions presented herein are based on the information available to us during our investigation, and some of those conclusions could be different if the information upon which they are based is determined to be false, inaccurate, or incomplete. Golder Associates makes no legal representations whatsoever concerning any matter including, but not limited to, ownership of any property or the interpretation of any law. Golder Associates further disclaims any obligations to update the report for events taking place after the time during which we conducted our assessment.

GOLDER ASSOCIATES PTY LTD per: fl

Mr Nick Withers Environmental Auditor - Contaminated Land Term of Appointment:

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11. REFERENCES

1. Guidelines for Environmental Auditors, Contaminated Land, Issue of Certificates of Environmental Audit, WM 9 1/14, Environment Protection Authority, Victoria, May 1992.

2. Environmental Site Assessment Stenson Road, Kealba. Prepared for Burgundy Bridge Pty Ltd by MacGregor Soil Engineering Pty Ltd (Australia) Pty Ltd, 5th August 1997.

3. EPA Bulletin No. 448. Classification of Wastes. Environment Protection Authority, Victoria, 1996.

4. Australian and New Zealand Guidelines for the Assessment and Management of Contaminated Sites. Australian and New Zealand Environment and Conservation Council. National Health and Medical Research Council, 1992.

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- FIGURES

Golder Associates 20 of 23 I((( I I Ill II I Ill I Ill1 32012-1-C

21 of 23 -- Golder Associates Pty Ltd A.C.N. 006 107 857 MELBOURNE OFFICE

25 Burwood Road, Hawthorn, Vic 31 22 Australia (PO Box 6079, Hawthorn West, Vic 31 22 Australia] S Telephone (03) 981 9 4044 Fax (03) 98 1 8 7990 CeIebraJing 25 years of Commifmenf to ENV'IROh'MEN'I' PROTECTION Am1970 f%'i"''in9 Lcellence SECTION 57AA CERTIFICATE OF ENVIRONMEXVTAL AUDIT

I, Nick Withers of Golder Associates Pty Ltd, a person appointed by the Environment Protection Authority (The Authority") under the Environment Protection Act 1970 ("the Act") as an environmental auditor for the purposes of the Act, having:

1. been requested by Mr Nick Polites of Burgundy Bridge Pty Ltd to perform an Environmental Audit in relation to the site at Stenson Road, Kealba, being that land described on Certificate of Title 1743 Folio 598 ("the site").

2. had regard to, amongst other things:

(i) guidelines issued by the Authority for the purposes of Section 57AA of the Act; (ii) the beneficial uses that may be made of the land at the site; and (iii) relevant State environment protection policieshndustrial waste management policies, namely;

EPA Information Bulletin "Guidelines for Environmental Auditors, Contaminated Land, Issue of Certificate of Environmental Audit", WM91/14 May 1992. EPA Information Bulletin "Classification of Wastes", Pub. 448, September 1995 EPA Explanatory Notes "Environmental Auditor System Contaminated Land", WM90/04, May 1992. ANZECC "Australian Guidelines for the Assessment and Management of Contaminated Sites", January 1992. EPA Publication 288 "Draft SEPP (Groundwaters of Victoria)",October 1994. ANZECC "Guidelines for the Laboratory Analysis of Contaminated Soils"

(iv) various reports relating to the condition of the site prior to remediation; and (v) the results of validation analysis of the site after remediation works were completed.

To be read in conjunction with Report 97613590/04 Page1 of2

OFFICES IN ADELAIDE, BRISBANE, CAIRNS, GOLD COAST, MAROOCHYDORE, MELBOURNE, PERTH, SYDNEY, WOLLONGONG. JAKARTA 22h!h\gi of 23 ASSOCIATED COMPANIES IN CANADA, FIJI, FINLAND, GERMANY, HONG KONG, HUNGARY, ITALY, SWEDEN, UNITED KINGDOM, UNITED STATES SYSTEM in making a total assessment of the nature and extent of any harm or detriment caused to, or the risk of any possible harm or detriment which may be caused to, any beneficial use made of the relevant segment at the site by any industrial process or activity, waste or substance (including any chemical substance); and

3. completed an environmental audit report in accordance with Section 57AA(2) of the Act, a copy of which has been sent to the Authority.

HEREBY CERTIFY that I am of the opinion that the condition of the land at the site is neither detrimental nor potentially detrimental to any beneficial use of the land at the site.

Dated:

Signed:

Nick Withers of Golder Associates Pty Ltd ENVIRONMENTAL AUDITOR - CONTAMINATED LAND

To be read in conjunction with Report 97613590/04 Page 2 of 2

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