Environment Protection Authority
Groundwater Prohibition Area – Portions of Hendon, Royal Park, Seaton and Albert Park
Determination Report EPA Ref: 61557, 05/22785
South Australia
Groundwater Prohibition Area – Portions of Hendon, Royal Park, Seaton and Albert Park
Determination Report EPA Ref: 61557, 05/22785
Author: Gabrielle Wigley
For further information please contact:
Information Officer Environment Protection Authority GPO Box 2607 Adelaide SA 5001
Telephone: (08) 8204 2004 Facsimile: (08) 8124 4670 Free call (country): 1800 623 445
Website: https://www.epa.sa.gov.au
Email: [email protected]
ISBN 978-1-921495-94-6
August 2019
© Environment Protection Authority
This document may be reproduced in whole or part for the purpose of study or training, subject to the inclusion of an acknowledgment of the source and to it not being used for commercial purposes or sale. Reproduction for purposes other than those given above requires the prior written permission of the Environment Protection Authority.
Contents
Abbreviations ...... 1
Summary ...... 3
1 Introduction ...... 5 1.1 Background...... 5 1.2 Legislative framework ...... 5 1.3 Extent of groundwater contamination ...... 6 1.4 Role of SA Health ...... 6 1.5 Role of site contamination consultant and site contamination auditor ...... 6
2 Site contamination – EPA information sources ...... 9 2.1 Documentation review and information in the EPA Public Register ...... 9 2.2 Site contamination in the Hendon, Royal Park, Seaton and Albert Park area ...... 9
3 EPA consideration for a GPA ...... 11 3.1 Conceptual site model ...... 11 3.2 Site history and surrounding land uses...... 11 3.3 Summary of regional and local hydrogeology...... 13 3.4 Characterisation of the nature and extent of soil and groundwater contamination ...... 18 3.5 Groundwater users ...... 52 3.6 Factors considered in the determination of the groundwater prohibition area ...... 52 3.7 Exposure pathways and human health risk assessment ...... 53
4 GPA consideration ...... 54
5 Community information ...... 55 5.1 Community engagement...... 55 5.2 Access to EPA information ...... 55
6 Conclusion ...... 56
7 Glossary ...... 57
Appendix 1 Summary of penalties and fees ...... 59
Appendix 2 Source site details ...... 60
Appendix 3 Details of reports available in the EPA Public Register ...... 61
Appendix 4 Chlorinated hydrocarbons ...... 70
Appendix 5 South Australian geology and hydrogeology ...... 72
List of figures Figure 1 Map of proposed groundwater prohibition area ...... 7 Figure 2 Map of information held by the EPA ...... 8 Figure 3 Satellite photo of the suburbs of Hendon, Royal Park, Seaton and Albert Park within the proposed GPA ...... 10 Figure 4 Geological and hydrogeological cross-section ...... 14 Figure 5 General flow of groundwater from the Mt Lofty Ranges across the Adelaide Plains ...... 14 Figure 6 Groundwater contour and sewer plan ...... 17 Figure 7 Groundwater flow direction and deep sewer main location ...... 17 Figure 8 Hendon industrial area ...... 19 Figure 9 Groundwater TCE results in March 2017 ...... 20 Figure 10 Groundwater PCE results in March 2017 ...... 21 Figure 11 Schematic map of source site with depiction of lateral extent of hydrocarbon plume ...... Error! Bookmark not defined. Figure 12 Inferred TCE plumes and known sources ...... 22 Figure 13 Inferred PCE plumes and currently known sources ...... 23 Figure 14 Simulated PCE plume as of 2017 ...... 24 Figure 15 Simulated PCE plume in 800 years ...... 25 Figure 16 Location of service station, Seaton ...... 26 Figure 17 Soil and groundwater bore locations at the service station, Seaton ...... 27 Figure 18 Former market garden, Seaton ...... 28 Figure 19 Soil and groundwater sampling locations at the former market garden, Seaton ...... 29 Figure 20 Vehicle storage and maintenance site, Royal Park ...... 30 Figure 21 Groundwater flow contours across the vehicle storage and maintenance site, Seaton ...... 30 Figure 22 Former commercial building, Royal Park ...... 31 Figure 23 Soil and groundwater investigations of the former commercial building, Royal Park ...... 32 Figure 24 Former service station, Royal Park ...... 33 Figure 25 On and off-site groundwater investigation wells at service station, Royal Park ...... 34 Figure 27 Location of Hendon Hotel ...... 36 Figure 28 Groundwater monitoring wells and soil bore locations at Hendon Hotel ...... 37 Figure 29 East–west geological cross-section of Hendon Hotel ...... 38 Figure 30 Petroleum hydrocarbon groundwater plume at Hendon Hotel ...... 39 Figure 31 Groundwater flow direction in the water table and semi-confined aquifers at Hendon Hotel ...... 40 Figure 32 Former electroplating site, Hendon ...... 41 Figure 33 Inferred groundwater flow direction from former electroplating site, Hendon ...... 42 Figure 34 Queensbury Wastewater Pumping Station, Hendon ...... 43 Figure 35 Former tin can facility, Albert Park ...... 45 Figure 36 Site features of former tin can facility, Albert Park ...... 46 Figure 37 Interpreted groundwater flow direction and reported TCE concentrations at Albert Park ...... 47 Figure 38 Former tannery, Albert Park ...... 49 Figure 39 Former tow truck operator site, Albert Park ...... 50 Figure 40 Former orchard and mixed manufacturing, Royal Park ...... 51 Figure 41 Former vacant land, Royal Park ...... 52 Figure 42 Microbial pathway for reductive dehalogenation for tetrachloroethylene (PCE) ...... 70 Figure 43 Electroplating bath ...... 71
List of plates Plate 1 Aerial photograph of the Philips site looking to the east in the 1960s ...... 12 Plate 2 SAFC Hendon Film Studios ...... 12 Plate 3 Underground storage tank removal, Hendon Hotel. Two points of corrosion are observed at both ends of the underside ...... 13
List of tables Table 1 Section 103S ...... 5 Table A1–1 Section 103S ...... 59 Table A1−2 Summary of relevant division penalties ...... 59 Table A3–2 EPA information sources recorded in the EPA Public Register − Hendon industrial area ...... 61 Table A3–2 EPA information sources recorded in the EPA Public Register − former automotive components facility (components site) ...... 63
Abbreviations auditor site contamination auditor or site auditor
BTEX benzene, toluene, ethylbenzene and xylene (petroleum hydrocarbon compounds) consultant site contamination consultant
DCE cis-1,2-dichloroethene
DEW Department of Environment and Water (formerly Department for Environment, Water and Natural Resources or DEWNR)
DNAPL dense non-aqueous phase liquid
EP Act Environment Protection Act 1993
EPA South Australian Environment Protection Authority
GPA groundwater prohibition and/or restriction area
Groundwater groundwater plume contaminant plume
IARC International Agency for Research on Cancer
LNAPL light non-aqueous phase liquid
NAPL non-aqueous phase liquid
PCE tetrachloroethene or perchloroethene
SA Health Department for Health and Wellbeing (South Australia)
S83A Section 83A Notification of contamination that affects or threatens groundwater
TCE trichloroethene
TDS total dissolved solids
VC vinyl chloride
VSRP voluntary site remediation proposal
US EPA United States Environmental Protection Agency
WHO World Health Organization
1
Summary
In South Australia, section 103S of the Environment Protection Act 1993 (EP Act) establishes the legislative framework for the prohibition and/or restriction on taking water affected by site contamination. In establishing a groundwater prohibition area (GPA), the Environment Protection Authority (EPA) must be satisfied that there is site contamination that affects or threatens water, and action is necessary to prevent actual or potential harm to human health or safety.
On 12 September 2019, the EPA will establish a GPA in portions of Hendon, Royal Park, Seaton and Albert Park (Figure 1). The GPA will encompass the upper Quaternary aged unconfined aquifer (Q1) and the lower semi-confined aquifer (Q2), and extends to a depth of 10 m below ground level.
This report provides a comprehensive summary of the technical information reviewed by the EPA, in consideration of establishing a GPA. The EPA aims to provide concise information in relation to the GPA and describe the roles of SA Health, site contamination auditors, site contamination consultants and the EPA. Additionally, this report outlines the legislative framework applied by the EPA in establishing a GPA.
The description of the review process is intended to assist local residents, businesses, community groups, local schools, kindergartens, childcare centres and the City of Charles Sturt in understanding why the EPA considers a prohibition on the taking of groundwater to be necessary.
This report provides a description of the proposed area, the aquifers affected, justification for a buffer area, specific details relating to the source sites, and the historical and ongoing assessment and remediation of these sites.
Details of the GPA will be placed in the EPA Public Register1.
Future purchasers of properties within the GPA will be made aware of the prohibition and/or restriction on the taking of groundwater via the Form 1 statement according to section 7 of the Land and Business (Sale and Conveyancing) Act 1994.
A person must not contravene the prohibition. A maximum penalty of $8,0002 applies (Division 5 fine).
It is important to note that SA Water mains and rain water are not affected by the GPA.
For further information please contact: Site Contamination Branch Telephone: (08) 8204 2004 Environment Protection Authority Freecall (country): 1800 729 175 GPO Box 2607 Website: www.epa.sa.gov.au Adelaide SA 5001 Email: [email protected]
For health-related information please contact: Scientific Services Branch Telephone: (08) 8226 7100 Public Health Services SA Health website: https://www.sahealth.sa.gov.au PO Box 287 Email: [email protected] Adelaide SA 5000
1 Pursuant to section 109 of the EP Act 2 At the time of publication of this report 3
Groundwater Prohibition Area – Hendon and surrounds 1 Introduction
1.1 Background
In South Australia, groundwater is widely regarded as an important supplementary resource to mains and rain water. In recent time, variable seasonal weather conditions have placed an increased demand on groundwater use for domestic and irrigational purposes. This led to an increased risk of human exposure to chemical substances that may exist in the groundwater. Contamination arising from point sources and diffuse sources within the aquifers can threaten the health of the whole aquifer system, the environment and potential groundwater users.
1.2 Legislative framework
Part 10A of the Environment Protection Act 19933 (EP Act), establishes a legislative framework for managing site contamination in South Australia, including provisions4 which enable the Environment Protection Authority (EPA) to prohibit or restrict the use of groundwater (Table 1).
In establishing a groundwater prohibition area (GPA), the EPA must be satisfied that there is site contamination that affects or threatens groundwater, and that action is necessary to prevent actual or potential harm to human health or safety.
If groundwater is affected by contamination and there is a likelihood that it may be used for domestic or irrigation purposes, then the consideration for the establishment of a GPA is warranted.
The establishment of a GPA can eliminate the pathway between the contaminated groundwater and human contact, and prevent or eliminate human exposure to the contaminants of concern. A GPA provides a long-term regulatory solution in which the use of groundwater may be prohibited for any purpose or restricted in post-abstraction (extraction) uses. There may be exemptions for groundwater monitoring or industrial use. A GPA may be necessary in circumstances where other remediation approaches are not adequate to address risks to human health associated with groundwater contamination.
Table 1 Section 103S
Section 103S – Prohibition or restriction on taking water affected by site contamination
(1) If the Authority is satisfied that – (a) there is site contamination that affects or threatens water; and (b) action is necessary under this section to prevent actual or potential harm to human health or safety, the Authority may, by notice in the Gazette, prohibit or restrict the taking of the water. (2) A notice under this section must – (a) specify the water to which it relates; and (b) give particulars of the site contamination affecting the water. (3) A person must not contravene a notice under this section. Penalty: Division 5 fine. (4) The Authority may, by notice in the Gazette, vary or revoke a notice under this section.
A maximum penalty5 of $8,000 applies for the contravention of a notice under section 103S of the Act (Appendix 1).
3 www.legislation.sa.gov.au/index.aspx 4 Pursuant to section 103S of the EP Act 5 At the time of publication of this report 5 Groundwater Prohibition Report – Hendon and environs
1.3 Extent of groundwater contamination
Figure 1 identifies the parcels of land within the GPA in portions of Hendon, Royal Park, Seaton and Albert Park. Groundwater from the upper Quaternary aged unconfined aquifer (Q1) and the lower semi-confined Quaternary aged aquifer (Q2) [0–10 metres below ground level] are known to be contaminated. The underlying Neogene and Paleogene aged aquifers (known as the Tertiary aquifers) are not known to be affected by site contamination arising from the known contamination sources in the area.
Conceptual site models developed during the assessments of known industrial and manufacturing sites within the Hendon Industrial Area have been considered. Consideration has also been given to assessments undertaken in the vicinity of these sites, in the wider Hendon, Royal Park, Seaton and Albert Park precincts (Figure 2), such as historically audited sites, notifications of site contamination to the EPA and service stations that the EPA is regulating. Details of sites where contamination has been assessed to be contributing to groundwater contamination is presented in Appendix 2.
1.4 Role of SA Health
The EPA requests advice from SA Health to determine if ‘action is necessary to prevent actual or potential harm to human health or safety’. SA Health has recommended that;
… it is reasonable to lower the direct community exposure to groundwater contaminants in the affected suburbs and, more generally, where groundwater exceeds relevant health-based guidelines, through groundwater prohibition. Therefore, the proposed GPA is supported.
1.5 Role of site contamination consultant and site contamination auditor
1.5.1 Site contamination consultant
A site contamination consultant (consultant) is defined in section 3(1) of the EP Act as:
… site contamination consultant means a person other than a site contamination auditor who, for fee or reward, assesses the existence or nature or extent of site contamination.
A consultant’s role is to design, prepare and undertake the assessment and/or remediation work in accordance with a mutually agreed scope of works, between the client and consultant.
1.5.2 Site contamination auditor
Site contamination auditors (auditors) are experienced site contamination professionals who are accredited by the EPA. The accreditation process is rigorous and intentionally sets a very high standard. Auditors independently examine and review the work undertaken by the consultants and provide their written opinions and determinations in the form of a site contamination audit report. The auditor provides an independent review of the assessment undertaken by providing a site contamination audit report6 or site audit report7. A person must not have a conflict of interest or prepare false or misleading reports8. The penalties for auditors providing false or misleading statements can include imprisonment9.
Audit reports are currently being prepared by auditors for various parcels of land within the proposed GPA (Figure 1). Details of the audit commencements are provided in Appendix 3. Once complete, the site contamination audit reports will be placed in the EPA Public Register10 and are available on request. For further information regarding the role of auditors refer to the Guidelines for the site contamination audit system (EPA 2015).
6 Produced after 1 July 2009 7 Produced before 1 July 2009 8 Pursuant to section 103ZB of the EP Act 9 Pursuant to section 103X of the EP Act 10 Pursuant to section 109 of the EP Act 6 Groundwater Prohibition Area – Hendon and surrounds
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7 Groundwater Prohibition Report – Hendon and environs
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8 Groundwater Prohibition Area – Hendon and surrounds 2 Site contamination – EPA information sources
2.1 Documentation review and information in the EPA Public Register
In compiling this report, the EPA has considered information from multiple sources in the wider area of Hendon, Royal Park, Seaton and Albert Park. The documents reviewed are recorded in the EPA Public Register. A list of these reports, including peripheral sites in West Lakes and Cheltenham, is presented in Appendix 3.
Further information on viewing or obtaining the reports is available from the EPA, telephone: (08) 8204 2004 or 1800 623 445 (free call for country users), website: https://www.epa.sa.gov.au or email: [email protected].
Additional information may be placed in the Public Register after the completion of the GPA determination report for any associated works at sites previously assessed.
2.2 Site contamination in the Hendon, Royal Park, Seaton and Albert Park area
The EPA holds reports and associated information relating to site contamination on various sites or parcels of land within the Hendon, Royal Park, Seaton and Albert Park area as listed below.
• Hendon Industrial Area, Hendon
• Service station, Seaton
• Former market garden area, Seaton
• Vehicle storage and maintenance site (former service station), Royal Park
• Commercial building (restaurant and hairdresser), Royal Park
• Former service station, Royal Park
• Hendon Hotel, Royal Park
• Former manufacturing and electroplating facility, Hendon
• Queensbury pump station, Hendon
• Former tin can manufacturing facility, Albert Park
• Former tannery, Albert Park
• Former tow truck operator, Albert Park
• Former orchard and mixed manufacturing, Royal Park
• Former vacant land, Royal Park.
The source site details and certificates of title are listed in Appendix 2 and maps showing information held by the EPA in the GPA area and satellite photo are illustrated in Figures 2 and 3, respectively.
The most pervasive known source of contamination arises from the Hendon industrial area in the form of volatile chlorinated hydrocarbons.
9 Groundwater Prohibition Report – Hendon and environs
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Figure 3 Satellite photo of the suburbs of Hendon, Royal Park, Seaton and Albert Park within the GPA
10 Groundwater Prohibition Area – Hendon and surrounds 3 EPA consideration for a GPA
3.1 Conceptual site model
The conceptual site model is developed to understand the relationship between source, pathways and receptors with respect to site contamination. A diagram is usually used to assist in describing the various exposure pathways and their relevance. A written model is an alternative or accompaniment to a diagrammatic model. The development of the conceptual site model includes the identification of all sources, modes of migration, all potential receptors of concern, and how exposure may occur (ie exposure route).
This section describes the conceptual site models for the sites summarised in section 2.2.
The development of a conceptual site model comprising the following, assisted in the consideration of the GPA:
• a desktop study of sites where site contamination has been identified and notified to the EPA
• summary of regional hydrogeology
• characterisation of contaminants of concern identified in assessments, nature of groundwater contamination
• local hydrogeology, extent of groundwater contamination
• consideration of areas of specific aquifer conditions
• determination of groundwater quality, including seasonal variations and surface water influences
• identification of environmental values
• identification of exposure pathways (ie the existence of private wells within the GPA)
• a human health risk assessment.
All the figures in this determination report represent the development of the conceptual site models through observational and intrusive investigations at the sites and their surrounding areas, within the GPA.
3.2 Site history and surrounding land uses
The suburbs of Hendon, Albert Park, Seaton and Royal Park, and surrounding suburbs are within the traditional lands of the Kaurna people.
Within a portion of Albert Park, 60 acres of land was established in 1920, as the Hendon Aerodrome by aviation enthusiast Harry Butler. In 1921 Butler sold a 20-acre portion of the land to be developed for residential housing in the suburb of Hendon. In July 1922, the Department of Defence compulsorily acquired the remainder of the site and purchased additional land to again extend the airfield to 70 acres. The Department of Defence continued to operate the aerodrome for the aerial mail service until 1927 when residential development in the area started to encroach on the safety of the aviation operations. The Adelaide Aerodrome was then relocated in 1927 to Parafield 11.
During the Second World War, a portion of the former Hendon Aerodrome land was developed as a munitions factory by the Commonwealth Government and works commenced producing small arms ammunition for the war effort12.
Philips Electrical Industries (Philips) bought the factory in 1947 to produce transistor and integrated circuits. During the 1970s Philips produced electrical goods such as radios, televisions and other domestic appliances at the Hendon factory. In 1980 the Hendon munitions factory site was renamed the Hendon industrial area13. Various electronics businesses still operate in the vicinity (Plates 1 and 2).
11 Marsden S 1977, A History of Woodville, Corporation of the City of Woodville, Griffin Press Ltd, Netley, SA. 12 https://www.charlessturt.sa.gov.au/webdata/resources/files/Local_history_factsheet_-_Hendon.pdf 13 http://www.weekendnotes.com/forgotten-places-adelaide-north-west/ 11 Groundwater Prohibition Report – Hendon and environs
Photo 1 Aerial photograph of the Philips site looking to the east in the 1970s
Photo 2 SAFC Hendon Film Studios (The Advertiser July 2011)
Within the GPA, various current and historical service stations have contributed to the soil and groundwater contamination. With the increase in motor vehicle use in Adelaide after the Second World War petrol stations were built at most major intersections along main roads. Many of these petrol stations were decommissioned and divested in the early 1990s and the remaining stations were upgraded into service stations, selling a variety of products, including fuels.
During a site history investigation undertaken by the EPA in 2014, it was identified that at least five petrol stations existed along Tapleys Hill Road in Seaton, Hendon and Royal Park, three of which have been decommissioned and are now utilised as commercial properties.
As part of the fuel dispensing infrastructure these petrol stations contained underground storage tanks and underground pipework. Due to the steel or fibreglass composition of historical underground storage tanks and associated pipework, corrosion and cracking can compromise the integrity of the tanks and/or pipes resulting in a loss of fuels to the surrounding environment 14.
14 Fetter CW 1999, Contaminant Hydrogeology, 2nd edition, reissued by Waveland Press, Illinois, USA. 12 Groundwater Prohibition Area – Hendon and surrounds
A small number of businesses and schools have historically utilised underground storage tanks for the storage of heating fuel for boilers within the property buildings. Corrosion of these steel tanks and/or associated pipework has generally also occurred, giving rise to contamination of soils and groundwater (Plate 3)15 16 17.
Site contamination has also occurred from other industrial activities in the area, such as electroplating, leather tanning and dry cleaning. Historically chlorinated hydrocarbons, cyanide and heavy metals released into the groundwater was commonly known to occur as a result of electroplating process solution spills, dry cleaning solution spills, equipment and pipeline leaks, and improper disposal practices.
Photo 3 Underground storage tank removal, Hendon Hotel. Two points of corrosion are observed at both ends of the underside18
3.3 Summary of regional and local hydrogeology
The GPA is situated within the Adelaide Plains (Metropolitan Adelaide) groundwater system (aquifers) which exist within the inter-bedded Quaternary sands, gravels, silts and clays that are deposited along the river channels and across the alluvial plains (Figure 4). Geographically, the general area is within the central alluvial plains north of the River Torrens. Geologically, the area is situated where the marginal marine sediments of the Glanville Formation overlie the terrestrial deposits of the Pooraka Formation19 and the Hindmarsh Clay20. On the western side of Tapleys Hill Road ancient consolidated sand dune ridges have been observed stretching from Port Adelaide to the Sturt River21.
Six Quaternary aquifers, named Q1–Q6, are supported by the deposited Quaternary aged shallow marine sediments of the Glanville Formation and the terrestrial sediments of the Hindmarsh Clay. Within the sediments of the aquifers, there are higher transmissive zones of sand and gravel beds, and these are generally separated by lower permeable silts and clays. Various gradings of silty clays and sandy silts have been observed through intrusive drilling investigations in the lower permeably beds (Figure 4).
15 AGC Woodward–Clyde 1992, Groundwater contamination assessment, BP Seaton. 16 BC Tonkin and Associates 1991, Site Contamination Assessment Investigation Report, Esso Australia, Royal Park. 17 SKM 2008, Hendon Hotel Remediation Project, UST Removal and Natural Attenuation Evaluation Report. 18 As above. 19 Taylor JK, Thomson BP and Shepherd RG 1974, The Soils and Geology of the Adelaide Area, Department of Mines Geological Survey of South Australia. 20 Gerges N 2006. Overview of the hydrogeology of the Adelaide metropolitan area, Report DWLBC 2006/10, Department of Water, Land and Biodiversity Conservation, Government of South Australia. 21 Fenner C and Cleland JB 1935, The Geography and Botany of the Adelaide Coast, Rigby Ltd, Grenfell St, Adelaide. 13 Groundwater Prohibition Report – Hendon and environs
OUARTERNARY AQUIFERS TERTIARY AQUIFERS
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22 Gerges N 2006. Overview of the hydrogeology of the Adelaide metropolitan area, Report DWLBC 2006/10, Department of Water, Land and Biodiversity Conservation, Government of South Australia. 23 As above 14 Groundwater Prohibition Area – Hendon and surrounds
Underlying the Quaternary sediments are the Tertiary (Paleogene and Neogene) sandstone and limestone sedimentary sequence. The Tertiary aquifers, within this sequence, are confined beneath the overlying thick Hindmarsh Clay unit. The first Tertiary aquifer (T1) comprises the Hallett Cove Sandstone and the second Tertiary aquifer (T2) comprises the Port Willunga Formation, separated by the Munno Para Clay (Figure 4). Two deeper Tertiary aquifers are anticipated to underlie the T1 and T2 aquifers. However, they have not been widely developed as a groundwater resource, primarily due to drilling depth constraints (>400 m).
Groundwater generally flows through the aquifers of the Adelaide Plains from the Mount Lofty Ranges in the east to the Gulf St Vincent in the west where groundwater discharge occurs. Figure 5 shows a general cross-sectional model of the groundwater movement across the Adelaide Plains. The geology and hydrogeology of South Australia is broadly summarised Appendix 5.
3.3.1 Specific aquifer and lithological conditions – Quaternary aquifers
In addition to reviewing the findings and outcomes of the site contamination assessment reports and audit reports (Appendix 3), the EPA completed a desktop review of additional information on hydrogeological conditions and groundwater contamination in the vicinity of Hendon, Royal Park, Seaton and Albert Park.
These reports have identified the first Quaternary aquifer, comprising fine to medium grained gravelly sand, to be an unconfined aquifer which forms the water table. This aquifer has been observed, through groundwater drilling, to occur at depths 3–4 m below ground level.
The depth to the semi-confined second Quaternary aquifer, comprising fine to medium grained sands within the silty clay of the Hindmarsh Formation, was observed at depth 8–9 m below ground level24. Information on the second Quaternary aquifer has been collated from a limited number of groundwater wells in the area. Two nested groundwater well pairs have been developed in Seaton directly south of the Hendon industrial area25 to assist in the determination of hydraulic head difference between the first and second Quaternary aquifers. Through groundwater gauging events the second Quaternary aquifer has been identified to be semi-confined with an upward hydraulic gradient.
Intrusive investigation around a service station in the Royal Park identified a thick water-bearing sandy layer between 5.5 and 8 m below ground level26. Investigations in the whole of the Hendon, Royal Park, Seaton and Albert Park area on the continuity of this lithological unit has not been undertaken to a large degree. There is, however, some documented relationship to the marginal marine sediments in the eastern portion of the Adelaide Coastal Plain and within the subsection of the Adelaide Coastal Plains Sub-basin 27 28.
In general, lithological investigations in the Hendon, Royal Park, Seaton and Albert Park area have identified highly variable sediments of sandy clay/silty sand/silty clay profiles with distinctive sandy layers and occasional gravel lenses29. Sand and gravel lenses within the aquifer material can contribute to preferential pathways of groundwater flow, both along the horizontal profile of the aquifer and between incomplete confining layers.
3.3.2 Specific aquifer conditions – Tertiary aquifers
Two definable Tertiary aquifers in the GPA, underlie the Quaternary aquifers. The Tertiary sediments are separated from the Quaternary aquifers by a massive clay layer which confines the Tertiary aquifers and creates an upward hydraulic
24 Parsons Brinkerhoff 2013, Additional Site Assessment, Hendon SA. 25 As above 26 Rust PPK 1996, Site Investigation and solute transport modelling – deeper sand layer – Esso Royal Park. 27 Smith ML, Fontaine K and Lewis SJ 2015. Regional Hydrogeological Characterisation of the St Vincent Basin, South Australia, Technical report for the National Collaboration Framework Regions Hydrogeology Project, Geoscience Australia. 28 Fenner C and Cleland JB 1935, The Geography and Botany of the Adelaide Coast, Rigby’s Ltd, Grenfell St, Adelaide. 29 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 15 Groundwater Prohibition Report – Hendon and environs head or upward pressure on the confining clay. This is widely supported by a hydrogeological study undertaken by Dr Nabil Gerges30 and was presented in a Department of Water, Land and Biodiversity Conservation31 report in 2006.
3.3.3 Groundwater quality
The Quaternary hydrogeology in the area of Hendon, Royal Park, Seaton and Albert Park, is largely defined by the terrestrial alluvial deposits of clays and sands. Marginal sandier deposits overlying the alluvial sediments have been identified in the western areas of Royal Park.
The salinities, within the upper two Quaternary aquifers range between 370 mg/L to 11,850 mg/L total dissolved solids when measured during the groundwater monitoring events or laboratory tested at a National Association of Testing Authorities accredited laboratory32. Salinity measurements are highly variable throughout the area and this is generally associated with the variability within the lithology of the aquifers. The salinity measurements are comparable from the limited number of groundwater wells developed into the second Quaternary aquifer.
3.3.4 Surface water influences
In 2014, there was an indication through assessments undertaken on behalf of the EPA that preferential pathways for contaminant migration existed along West Lakes Boulevard and Tapleys Hill Road. At that time, it was thought possible that a deep vitreous clay sewer line beneath Tapleys Hill Road could act as a preferential migration pathway for contaminated impacted groundwater33.
On further investigations in 2015 it was inferred that incidental groundwater draining34 from the sewer line is contributing to an observed variable groundwater flow direction west of Tapleys Hill Road. Measured groundwater gradients in 2014 support the fact that the sewer line may be acting as a drain for groundwater within the local area (Figures 6 and 7) 35 36.
Investigations around the deep mains sewer line also indicates lateral migration of contaminated groundwater37. The identification of groundwater mounding south of the GPA was thought to be from an underground drainage system 38, which may be attributed to the deep mains sewer line.
Surface water losses from the groundwater system due to evapotranspiration are not considered to be a significant discharge mechanism in the area because groundwater levels are generally below the depth of the vegetation root zone. Eucalypts and deep rooting vegetation are known exceptions39.
30 Gerges N 2006, Overview of the hydrogeology of the Adelaide metropolitan area, Report to DWLBC 2006/10, Department of Water, Land and Biodiversity Conservation, Government of South Australia. 31 Department of Water, Land and Biodiversity is now known as the Department for Environment and Water. 32 Field analysed total dissolved salts is calculated by applying a factor of 650 to electrical conductivity recorded data. 33 Parsons Brinkerhoff 2014, Additional Site Assessment, Hendon, SA. 34 URS 2015, Environmental Investigations (Stage IV), Hendon, SA. 35 Parsons Brinkerhoff 2014, Additional Site Assessment, Hendon, SA. 36 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 37 Parsons Brinkerhoff 2014, Additional Site Assessment, Hendon, SA. 38 Coffey Partners International 1992, Environmental Site Assessment Summary Report, Delen Corporation site, 3–5 Philips Crescent, Hendon. 39 Doucette WJ, Chard JK, Fabrizius H, Crouch C, Peterson MR, Carlsen TE, Chard BK and Gorder K 2007, ‘Trichloroethylene uptake into fruits and vegetables: three-year field monitoring study’, Environmental Science Technology 41: 2505–2909. 16 Groundwater Prohibition Area – Hendon and surrounds
- Sewer ma'n
Hendon Additional Environ.mental Site Assessment _,, .., Figure.4 ~--·-··· -·---- ______Groundw.l.ter Contour and Sewer Pl.in • March 2014 ~- ...= ....=---;.-~:::--;:;: ._..,_ ,,..-.-r,..,.....111~ ----~~ Figure 6 Groundwater contour and sewer plan40
___,,r,.... '1rerret:1 GrolilltwatS" fIOw ----v- Otn:c!on Groundwater Wells usecs ~ OC::Dber 2Cl 16 and • f ellnJary2017 Orrtt:ed tl'tlm octooeJ 2016 Orrtt:edtl'tlm f ebfllal)' 21117 Orr:tt:ed tl'tlm OciooeJ16 and Fetm,DI)' 2017
Location: Hendon Broader Assessment Area Figure D 0 50 100 150 200 Inferred Groundwater Flow Contours - - I m CoonM~~ Sys, = :GOll 1P".t U3A2.Clt:i~ o,I. M!lai:;ff)' t:,1~ fiow:m~I !.\Of c u =.._, r~1 Figure 7 Groundwater flow direction and deep sewer main location41
40 Parsons Brinkerhoff 2014, Additional Site Assessment, Hendon, SA. 41 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 17 Groundwater Prohibition Report – Hendon and environs
3.4 Characterisation of the nature and extent of soil and groundwater contamination
When site contamination of groundwater is known to exist, the quality of the local groundwater or aquifer is impacted. Groundwater assessments have been undertaken in the GPA to determine the nature and extent of groundwater contamination and the risk to potential users. Due to the physical and hydrogeological characteristics of an aquifer system, the removal of the source of contamination will not remove the contamination from the groundwater. However, a process of natural attenuation of contaminants in the groundwater exists, where the speed of the contaminant depletion is dependent on the nature of the aquifer42.
In accordance with the Guidelines for the assessment and remediation of site contamination (EPA 2018) where site contamination exists that is not trivial, implementation of soil and groundwater assessment and remediation may be necessary. The National Environmental Protection (Assessment of Site contamination) Measure 1999 (as amended in 2013) has also been developed as a nationally consistent approach to the assessment of site contamination. Assessments will generally comprise a site history investigation, geological and hydrogeological site characterisation, and investigation of the site contamination, including contaminants of concern and human health risk assessments.
Remediation generally commences following the development of a remediation options assessment. In South Australia remediation includes treatment, containment, removal or management of chemical substances on or below the surface of the site43.
The environmental assessment reports prepared in relation to the sites in the GPA document the potentially contaminating activities that were undertaken at the site, and the known soil and groundwater contamination (Appendix 3).
3.4.1 Hendon Industrial Area (Figure 8)
Nature of contaminants in the Hendon Industrial Area
Intrusive environmental assessment, undertaken in relation to the Hendon industrial area in 1992, identified groundwater contamination on the site, and off site up and down gradient locations. Initial investigations commenced with the initiation of a due diligence land sales agreement at 3–5 Philips Crescent, Hendon. Following this, the EPA commenced a desktop review of historical information for the broader Hendon industrial area to identify a party liable for the known site contamination. As a priority to determine any risks to residential properties, schools and childcare centres, the EPA engaged consultants for the assessment and development of a conceptual site model to assist in this determination of risk.
Various activities in relation to electronic component manufacturing were undertaken at the site in the Hendon industrial area.
As part of a due diligence assessment at 3–5 Philips Crescent, Hendon, consultants identified metals, including copper, tin and lead in soil in the vicinity of underground sumps. The soil samples were not comprehensively tested for chlorinated hydrocarbons, however volatile hydrocarbons were detected using a photo ionising (ionisable by a 10.6 eV lamp) semi-quantitative technique44. Initial remediation at the site included the removal of chemical wastes from onsite sumps and multiple above ground and underground waste storage tanks located within and external to the manufacturing buildings. Targeted removal of contaminated soils in the vicinity of the chemical waste sumps was also undertaken,
42 Wiedemeier TH, Rifai HS, Newell CH and Wilson JT 1999, Natural Attenuation of Fuels and Chlorinated Solvents in the Subsurface, John Wiley & Sons, New York, USA. 43 Pursuant to section 3 of the Environment Protection Act 1993 44 Coffey Partners International 1992, Second Stage Environmental Site Assessment and Site Remediation, Delen Corporation site, 3–5 Philips Crescent, Hendon. 18 Groundwater Prohibition Area – Hendon and surrounds
Produced by Knowledge. lnlormal POn & Strategy Hendon Industrial Area Em1ronmen\ Protection Authority GPO Bm 2607 [email protected] SA 5001 ~ Audit Data Source ~~~ta.gov.au Compiled 20Augu,t2019 N Ptojectiol'I Larnb8rtConfaoma lCooie • • • • EPA Groundwater Datum Gooccntric Dillum of Aust r,;:iW.i, 1994 ;~~:1;.,,I~,~;~ '";.";'i-<,',".£\~~/:1·•; 1t ;.,..,J..f,;,,, :,,%.:;.;.,, ;..;.. ~ 1:: 11,, • •• Prohibition Area 250 A ~~~::;,.,,w,.;..,~ ~.::;;•\•"l~,o,~....,. .. ,.,;; ,~1:~-~•,::7?•": Suburb Metres
Government e>fSouth Austr_,.1 ;.,.
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Figure 8 Hendon industrial area
19 Groundwater Prohibition Report – Hendon and environs
However during this initial stage of remediation, it was determined that a broader remediation of soils was not necessary given the continued use of the site for industrial purposes45.
With regards to groundwater in the investigated southern portion of the Hendon industrial area, leaching of contaminants of concern has impacted the groundwater with cadmium, cobalt, copper, nickel and zinc. Chlorinated hydrocarbons have also been identified in the groundwater (Figures 9 and 10). At the time of these initial investigations, the consultants engaged to assess the southern area believed that the site contamination within the groundwater was derived from site activities and activities in the broader Hendon industrial area to the northeast46. Site activities undertaken in the southern portion and in the broader Hendon industrial area included electroplating and printed circuit board manufacturing47.
1nc1 rca.M L-ocatlon a; SEwaiMail s GroorKtwater Mon ,Dr1ng well •• GroorKtwater Monl:Ddng well {ba; TCE Concentration (l,Jg/L) C]<20 □ 20 - 1 00 □ 1 00-200 . □ 200-,00 C] soo - 1,000 - • 1.000
Project: Location: Hendon Broader Assessment Area Figure D O 60 120 180 Groundwater TCE Results Plan Da:e: June 2017 Ct10fmo11~.Sys;rem: GOJ!, f pjt.,I WllZMt µ (March 2017) ~ ,1ae,oy l=:,l !!:J NOYefr.~-.I 2011!) 0 1'11! .am:-_,,, ~1 If)
Figure 9 Groundwater TCE results in March 201748
From 2013 to 2017, the EPA commissioned soil, soil vapour and groundwater assessments in the vicinity of the Hendon industrial area. The primary focus of these types of investigations was to determine if a risk to human health existed as a result of the historically contaminating activities at the Hendon industrial area. Understanding risks that may exist informs the type of remediation necessary to protect human health from contaminants of concern within the soil, soil vapour and groundwater.
Chlorinated hydrocarbons are the primary contaminants of concern within the Hendon industrial area. Chlorinated hydrocarbons assessed in the area include tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2 dichloroethene (DCE) and vinyl chloride (VC). Within the Hendon industrial area, chlorinated hydrocarbons were predominantly used as a cleaning product in the electrical component manufacturing process. Additional information regarding the nature of chlorinated hydrocarbons is presented in Appendix 4.
45 Coffey Partners International 1992, Results of Soil Gas Survey and Preliminary costings of selected site Remediation/Options, Delen Corporation site, 3–5 Philips Crescent, Hendon. 46 As above 47 As above 48 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 20 Groundwater Prohibition Area – Hendon and surrounds
.-illDial Area Q 3-S?tcp,C-SlteE«Jrmy Q ct1JOcareDemre D "1dooA1nmySChool
• Qrulol,
Proj ect: Hendon Broad er Assessment Area - Stag e 3 Works SCAl:..E (at A3) 1:5,0 00 Figure Location: He rlC!on Brooder Assessment Area I 0 60 120 180 240 Groundwater PCE Results Plan Jo~ Re ·_J 146787 Drawn : MN Checked: SW Date: June 2017 --==--=::::iMeters (Marc h 2017) Coc:r.:L,-..1e, ~ .-n:G[b( 1~ ~ZCll'l t' i;,t. tr: ;:i ~ r2,1m N11wernur 201Q c~ 1,t1J Figure 10 Groundwater PCE results in March 201749
Extent of contaminants in the Hendon industrial area
To determine the lateral and vertical lateral extent of groundwater contamination within the GPA, the EPA utilised information contained in the various environmental assessment reports (Appendix 3).
Analysis of groundwater has identified contaminants of concern in the lateral extension of the chlorinated hydrocarbon plume. The groundwater plume is generally large relative to the width of the source area. This can be mainly accounted for by periods of lateral northeast/southwest flow due to the changes in the hydraulic head of the water table from surface/groundwater interactions50. Seasonal changes in hydraulic head can be caused by domestic irrigation recharge and domestic abstraction of the unconfined aquifer.
Due to the semi-confining to confining nature of the clay sediments within the aquifer it is expected that there is an upward hydraulic gradient between the first, second and third Quaternary aquifers. Confinement between aquifers indicates that contaminants of concern dissolved in the groundwater are unlikely to move between aquifers. An exception is contaminants of concern moving through preferential pathways. This is not the case with diffused dense non-aqueous phase liquids, such as chlorinated hydrocarbons, which can migrate down and through the aquifer sediments via gravity forces51.
49 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 50 Sophocleous M 2002, ‘Interactions between groundwater and surface water: the state of the science’, Hydrogeology 10: 52–67. 51 Kueper BH, Stoo HF, Vogel CM and Ward CH, 2014, Chlorinated Solvent Source Zone Remediation, Vol 7 in the SERDP ESTCP Environmental Remediation Technology Series, Springer-Verlag, New York, USA. 21 Groundwater Prohibition Report – Hendon and environs
In determining the extent of contamination in the groundwater, the following factors require consideration:
• Hydraulic parameters, and more specifically, hydraulic conductivity estimates can be highly variable due to local heterogeneity of aquifer sediments.
• Contaminant migration is highly dependent on the aquifer hydrogeological conditions and natural attenuation parameters.
• During migration within the groundwater, contaminants attenuate by mechanisms of dispersion, adsorption, ion exchange, precipitation, co-precipitation and biochemical degradation. These processes occur until natural attenuation capacity is reached resulting in a reduction of contaminants in the groundwater.
• The process of natural attenuation, through biodegradation, varies considerably and contaminants will migrate with a non-linear longitudinal extent over time through the aquifer sediments until a stable plume extent is attained.
• Groundwater plume migration prediction (fate and transport modelling).
Due to these inherent uncertainties in hydraulic parameter values, mathematical calculations of linear groundwater velocity may differ from the observed plume front, by many hundreds of metres52.
Consideration of these factors are utilised in the calculations of the extent of chlorinated hydrocarbons in the groundwater plume arising from the Hendon industrial area (Figures 12 and 13).
When determining the extent of a groundwater plume, site contamination auditors and consultants at times rely on numerical fate and transport modelling to predict plume migration within the aquifer. This methodology has been utilised for the groundwater contamination plume arising from the Hendon industrial area. , , N' ' ~" ' I .,~~ '- _.,, ; l J j
MW1'iil U7 ... - ., ,:> ,' l.. , tP\\"" • " f H2U 5-3 ■HU OOII \ , I ' I ' , I I I + '1J I I wy ' 0 $ ' , ' ... - - .,, ~i , I I I :: ' , , , ' , , ' Cl~CUITOAIVE ' ' I - - - ;'lf:J ... ·-o,,_ - - . .i...... ' ' .•' ' ' ' ' ' ' , ·, ' , ' I ~ "'
@ Gruu11dwzt.t.r Monioring Wal 20 & muiinum TCI COflt-entration (ug}l.) . _..,_, ,...... 0,01- - .OroundWBler Level I CooCoUift- (mAHO) I I •• I. I ... ,.. 11.A : : : : :J .,. -'. eMW12"" , I ~~~ot , · I .....,~:... ,. ' , I I 0 I ~,; ~ wzr o ... :~'- ... , ~ I
Figure 12 Inferred TCE plumes and known sources53
52 Freeze RA and Cherry JA 1979, Groundwater, Prentice Hall, Englewood Cliffs, NJ, USA. 53 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 22 Groundwater Prohibition Area – Hendon and surrounds
, - !Hi z 5 ◄ . 02 I I I CIRCUI\ ORNE '\,, ·~_, _ - - .A· .. I , I I I :; , , I , I :; ...,. . I I I I I I MW22 (I) G""'--riogWo • I 0.01- - -=.=-,:..-.:~~ 7 • I ,. --• I -.. _ I • I , I . I I I I ;: .., I ~./ ~ i,IJ:z ,.,OJ3 - , { et,!Wn -4.02 I f!Mw2t 0Jl1 OM 40m - Figure 13 Inferred PCE plumes and currently known sources54 Groundwater plume migration prediction or fate and transport modelling can be subjective. This is due to the inherent difficulties in determining aquifer parameters from localised monitoring data. Conservative risk-based model predictions may be derived from utilising historical site information and measured groundwater monitoring data. Utilising observed time measured patterns can assist in informing the site numerical models for sensitivity analysis and model calibration reiterations. In this way using all data available can assist in predicting a conservative final plume extent55. To simulate the final extent of the groundwater plume arising from the Hendon industrial area, numerical modelling was used to simulate contaminant transport of contaminants of concern within the groundwater and to understand when the plume would reach a steady state56 or plume stability. Generally, the steady state of a plume within groundwater is the point at which the contaminants are not expanding within the aquifer, primarily due to the attenuation of chemicals being greater than the down gradient flow of chemicals with the groundwater. The numerical model utilised historical information such as location of the source of contaminants, measured contaminant concentrations and measured hydraulic conductivity. The transport model was then calibrated using contemporary monitoring data to predict the modelled extent of the groundwater plume. During the modelling calibration process it was identified that there were uncertainties within the modelling process due to the unknown relationship of the deep sewer to the groundwater flow regime and the indication that all the source sites have not been identified in the Hendon industrial area57. 54 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 55 Anderson MP and Woessner WW 2002, Applied groundwater modelling – simulation of flow and advective transport, Academic Press, San Diego, California, USA. 56 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 57 As above 23 Groundwater Prohibition Report – Hendon and environs The modelling predicted a frontal position for TCE and PCE for a current representation and an 800-year prediction where, during this time the model indicated that the plume achieved steady state (Figures 14 and 15). The disproportionate expansion in the northwest of the predicted representation is considered by the consultants to be an area where a small portion of contaminated groundwater passes an area where groundwater is influenced by the deep sewer main58. This is possibly not an accurate representation given that the interaction of the deep sewer main with groundwater and the identification of all source sites are areas of assessment uncertainty. The true interaction of the groundwater with the deep sewer main and the limited data on other sources of contamination in the area indicate data gaps in the conceptual site model. The northwest extension of the groundwater modelling is not considered suitable as a reliable source of information. As a result a buffer area is set up in the GPA footprint to provide conservative protection for the farthest extent of groundwater contamination. An auditor was engaged to audit the site, and to independently and objectively review the assessment by the consultants to determine that nature and extent of any site contamination present on or below the surface of the site. The auditor will also considered remediation necessary for the site. A site contamination audit report provides assurance that the assessment and remediation, if necessary, was undertaken satisfactorily. This is consistent with EPA guidance59 Figure 14 Simulated PCE plume as of 201760 58 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 59 EPA 2018, Guidelines for the assessment and remediation of site contamination. 60 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 24 Groundwater Prohibition Area – Hendon and surrounds Figure 15 Simulated PCE plume in 800 years61 61 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 25 Groundwater Prohibition Report – Hendon and environs 3.4.2 Service station, Seaton (Figure 16) 169–170 Tapleys Hill Road, Seaton - --1 -, - I I ' - Service Station, Seaton •• • • 1 EPA Groundwater -I I • • ■• Prohibiti on Area I I I I I I I I SfE\/ENi:il>IREET I 1 I T -, - I I I ' ■ • a a • • • ■ ■ • ■ ■ ■ ■ MATTHEWSAVENI.T. I I I I 1- I I I I I r_ _ I_ -I - J- ri-- r L - 1 I f- I --1 I I I I_I I I I I I I L_ I L L _J - N -i , r , A 00 I r .... w --- I I I I I I I i I I I '-I~ i- I ~ -1 ~ I r- I I 1 I 1 -i l f' IRST IWENU:' - -, I I -. I I I - --1 I_ --, L I I L ______c__'_~______l ______l~ ...... ,. GIS1 8_0029 Figure 16 Location of service station, Seaton The site is believed to have operated as a service station since 196162. Contamination of soil was identified in 1988 during the removal and replacement of degraded underground storage tanks. The tanks and associated fuel line infrastructure may have contributed to soil contamination at the site. Contaminated soils were removed at that time. Intrusive environmental investigations commenced at the site in 1992 to determine the extent of site contamination (Figure 17). The consultants engaged at the site initially identified significant petroleum hydrocarbon contamination within the soil at targeted locations. At that time, the soil contamination was noted to extend into the saturated zone below the water table63. With regards to groundwater, the existence of pervasive dissolved phase petroleum hydrocarbon contamination was identified in the water table aquifer, identified as the first Quaternary aquifer. Petroleum hydrocarbons within the groundwater onsite also include benzene, toluene, ethylbenzene and xylene. During the initial phase of assessment hydrocarbon light non-aqueous phase liquid was not identified. However the consultants have indicated that a sheen was visible on the water of various bores64. 62 AGC Woodward–Clyde 1992, BP Service Station Environment Site Assessment, Tapleys Hill Road, Seaton. 63 As above 64 As above 26 Groundwater Prohibition Area – Hendon and surrounds . •• ·--· I Figure 17 Soil and groundwater bore locations at the service station, Seaton65 Further assessment of groundwater impacts were investigated in July 1993 to understand the potential for off-site migration of contaminated groundwater. Groundwater levels indicated that groundwater movement is in a westerly direction and movement of contaminants is within this groundwater flow direction. As benzene was identified in groundwater on-site and beyond the neighbouring boundary of the site, it was considered that the groundwater plume extended below the western neighbouring properties and possibly further off site 66. 65 AGC Woodward–Clyde 1992, BP Service Station Environment Site Assessment, Tapleys Hill Road, Seaton. 66 AGC Woodward–Clyde 1993, Investigation of potential contaminant migration, BP, Seaton. 27 Groundwater Prohibition Report – Hendon and environs 3.4.3 Former market garden area, Seaton (Figure 18) 187–193 Tapleys Hill Road, Seaton - _...l _I L - Former Market Garden STF\ ·E:.$l>TRl:d - fl Tf -l •• • • 1 EPA Groundwater I • ■ ■ ■• Prohibition Area I J I I I H.ENDON , _[ l - -1 I Suburb -'- ~ j-1 T _ 1 1- I I I I I~ I ~ _ l I I I L ---j ~IOICLEY RUAD _J_ J _J 17 117 1-1 _I_ I ~ ..J 1--r I l I !_ I-1 I I I i 7 I 1 • ♦ I _J ■• ■ ■ ■ ■ -;- ISE€ONDt.VE~ ■ ■ ■ ■ ~ .;;. ♦ 1-1 ~ I~ - I_ I~I - ., - ~ • -1 - .J ~- i : , L 7 '+ 1------...!..-- I - _J : - ! I I I I I __L ~ _l I I _J__ TH IRll/1,VEr,;IJ!:: SEATON j : - N -1 · 1h i: T I : A I ■ ' T .,....,..--,r---'.'-----_,J ..... I I -· 1 __J r , , 1 , 1~ : ...l ~ ' I 11 I I 11 I -, j' : - ~.I•••~ • L I - _ I I _I_ LI : lL I_: I 1' ~ 1 ~ I _____j_ ■ _ _ • • • • • • • ■ ■ • ■ 10F1r:r.if.!Ol'l?l:1'«!1i!Dal ■ ■ ■ I j I I ~ _I 1 1 - 1- ' " """'~" • • • • • ~ : --i ~ - I1 ' - r 1 1 1 I I 1 I I l g f - ~ I I I I 1 1 I I · I I I 11 I 11 1 I I I -1 1 r- I t- J -1 --. I ' I I T Tl ~1 j__r _ '.i I l I I ' 1 I 1 - j I I I I ,-1'1 I I I I I1 I I - T ' _1_, , --'-T · _,_ 1, -1. I_ L I --• - 1 '""I ""'"IT I wooow~•~ ::-.::="?·:--;- RAYMUND /1.VC:N'J E ~ ,r- -,- -, I + r· L 11r, ,"• -1--'--' p , ':,:-:::·_ _· ::-,, I I I I 1,1 I I 1 1 _J ,, {_ _ -=_J_:1_I ~1-~I ~I ~_!__~I _' ~..L~J~ '- I ~l~ I ~l;;::_ ___~ "·:~"_$_ ~,l-/-~ , Cih.•·.·_ :,. ····",:·:...... :. ,: c,.: . ==~==T ~===~~===~~~~='-'~~ ::'.. W.IIU fl'IS RO!\D oit:."~i;::~~u~ . ' : GIS18_0029 Figure 18 Former market garden, Seaton A site audit report was undertaken at the site in 2008 in relation to a proposed development for a residential aged care facility to be constructed on the site. Intrusive investigations undertaken at the site during the audit identified significant groundwater contamination in the form of nitrates with minor metals (Figure 19). The auditor was engaged at the site to identify the contamination status of the land and to identify the types of land use or development that would not be compromised by the contamination on the site. The auditor considered that the site was not suitable for an unrestricted use, however the site is suitable for residential use and for other less sensitive land use including the proposed residential aged care facility, and subject to the condition that groundwater was not to be extracted for any use67. 67 Hall A 2008, 187–193 Tapleys Hill Road, Seaton SA – Site Audit Report. 28 Groundwater Prohibition Area – Hendon and surrounds Cl Sou NOTTO ktnt n;,o:TMI( ST i5 "' 1- ;;: Vl :::, > <( 80Cll!TYOF (2007 URS SCAL HILARION ® _!!1; E E~tent INC 01 Audit ]nN]/\V •- Draffl..l.M kb PIOJeCI -- O Ntl 1 VD~ . :.4-21::i&a7 i\ ~ A 1 !! ;:; i - llj ~ ~ ] 111~ REV 87-193 :l; "' .,., ~ "' .,_.- S · 1 ---t SITE l 8 t I SED Ftl1t ""1,11\~:A.YlJ TAPLEY$ 111 ~ SEATON • AUDIT i. : ii ;;! ~ N'o H ♦ lln :!l - EXTENT .:-42M6718 . J . . ♦ • ♦ ♦ + ~" ! ::: ill :St ., " i ii ~ ii ~ i REPORT SA lCJ H H I , L 0G1.a2' SAl L JON OF l'!OAD Oalb:AUGUST • t ♦ ♦ •~- i i i !,o,n,i " - ;:; i l i! m dVl AUDI ,. ~ T . • ♦ - • ♦ - -~ S 2006 ~ ~ f ~ ii " ili i I ~ !!! H fl: ~ ~ OWN Tfllo GROUNDWA Fig I • -t ure • • ♦ + 4-"! ♦ " l e iii ;:; SITE ~ ~ " ili ;:; ~ ; • i ! ~ ;; " : . ♦ .. E ;:; fi 2R AND l PLAN I "- 0 " T 0 ~ EXTEN ER SHOWING SAMPLING ;tttt! T OF AUDIT SOI LOCA L AN T D I R ONS IW A4 . A Figure 19 Soil and groundwater sampling locations at the former market garden, Seaton68 3.4.4 Former service station, vehicle storage and maintenance yard, Seaton (Figure 20) 168 Tapleys Hill Road, Seaton Preliminary soil and groundwater investigations were undertaken by consultants in 2018 at the former service station, vehicle and maintenance yard to determine the existence of site contamination to facilitate a proposed change in land use to a more sensitive use69. An audit was completed for the site in 2019 where the auditor formed the opinion that the site is suitable for a sensitive land use70. The preliminary assessment at the site recognised that groundwater contamination exists possibly arising from the Hendon industrial area, immediately east of the site. In addition to chlorinated hydrocarbons identified, potentially contaminating activities such as dispensing fuel and vehicle maintenance are believed to have been undertaken at the site 71. Groundwater elevation gauging of onsite monitoring wells have projected the groundwater to flow in a west– southwesterly directions (Figure 21). Which regards to the historical activities of dispensing fuel, the on-site groundwater assessment did not identify petroleum hydrocarbons72. Groundwater assessment, however, identified that site contamination does exist at the site, chemicals and substances include cadmium, zinc, nitrates and TCE. The auditor considers that the site is not the source of these impacts. Impacts are likely due to the contamination arising from the Hendon industrial area 73. 68 Hall A 2008, 187–193 Tapleys Hill Road, Seaton SA – Site Audit Report. 69 EPA 2018, Guidelines for the assessment and remediation of site contamination. 70 Kirsanovs S 2019, Site Contamination Audit Report, 162-168 Tapleys Hill Road, Royal Park, SA EPA REF 61987. 71 Land and Water Consulting 2018, Preliminary Site Investigation, 168 Tapleys Hill Road, Royal Park, SA. 72 As above 73 Kirsanovs S 2019, Site Contamination Audit Report, 162-168 Tapleys Hill Road, Royal Park, SA EPA REF 61987. 29 Groundwater Prohibition Report – Hendon and environs - Vehicle Storage Area - T Suburb r - I l_ I_ + I I_ l ~ _j_ ~ T 1- -, HEN DON I RO YAL PARK N 0 I,..,_ A J n I LJ ~ ..... , -~ .... ,. __ .,_.,.. _, - r~~ ··•:'""".>:;:;;, 0 -~£ --. ~ -% ~~i:. --'.~ .. :::,:.:·::.-.:·,.:·_: ::::::::::."S""'."'",•·· ,·· SEATON ---, GIS18_0029 Figure 20 Vehicle storage and maintenance site, Royal Park A -~~E.... tbftCMlta.Nlo•rt F..,_011.::!ui . J.1M•"·»1I Figure 21 Groundwater flow contours across the vehicle storage and maintenance site, Seaton74 74 Land and Water Consulting 2018, Preliminary Site Investigation, 168 Tapleys Hill Road, Royal Park, SA. 30 Groundwater Prohibition Area – Hendon and surrounds 3.4.5 Former commercial building, Royal Park (Figure 22) 150–152 Tapleys Hill Road, Royal Park An audit was completed at the site in 2013 for the purpose of changing the land use to a more sensitive residential use. No potentially contaminating activities were identified to have been undertaken at the site. The results of the soil assessment indicated that site contamination did not exist (Figure 23). The results of the groundwater investigations undertaken for the audit identified metals, petroleum hydrocarbons and chlorinated hydrocarbons. The auditor considered that the site contamination identified in groundwater are likely to be from an off-site source75. The auditor has conditioned that groundwater at the site should not be extracted for any use including potable, recreation/aesthetics, agriculture/aquaculture and industrial use. - - - Form.er Commercial I I I Building r -1-1 7 ---t- ~ I- - - I Suburb 7 I J I I + I I --t I I I - [_ ~ (IAK:;TR:C~T I I 1 L 7 I J_ 1 1 TI 1 r- -r 7 7 r I I i -1 I r ii 7 \; r I I I _I I [ 1_1 _ l ~ - -j j L 1 I - I -1 f I I I r- - I I I - R9YAL PARK f- - HENDON N ~ I I 1 I A 50 -1 l I ....I j_ -7 1- - 7 \I I 1- f I - l I_ i- I 9, _ _ ., ~;~":~'; "'"''"! Figure 22 Former commercial building, Royal Park 75 Ramsay PJ 2013, Site Contamination Audit of Land Pursuant to Part 10A of the Environment Protection Act 1993. 31 Groundwater Prohibition Report – Hendon and environs D1 0 5rrrn BH 1 BOO!llole t-1..-nber aM ocallan Approximate Scale • K,AJll11 ~ 1.2) BH 1 ~ 1 BCi'elllale t-1..-nber anm ca111Jn 1------• K, Decemlla 2 □ 1 2 ) • GW 111 E.~ndw.t. 1Martlllr1~ \Ve ,S,_A.;.,~:e:-20¼\3-ec..m.,. Figure 23 Soil and groundwater investigations of the former commercial building, Royal Park76 3.4.6 Former service station, Royal Park (Figure 24) 136–138 Tapleys Hill Road, Royal Park The site operated as a service station from 1959 until it was decommissioned in 1990. During the decommissioning works, all infrastructure was removed. Since 1990, the site has operated as a plant hire facility and a traffic management site 77. 76 Ramsay PJ 2013, Site Contamination Audit of Land Pursuant to Part 10A of the Environment Protection Act 1993. 77 BC Tonkin & Assoc 1991, Site contamination assessment investigation report, Royal Park, SA. 32 Groundwater Prohibition Area – Hendon and surrounds I I -T -I - :~~;e;,i~~!~ 0Park I I L- I I Suburb 1- -1 - 7 - I I -=1 I I I I r- - r • I __j_ IL_ -' ,- i 1------r I I 1- f- _J_ - j I I - I I .,._ - I I I I _J_ I SOP,~1Tlt hl/1:NUi:. I ~ _ j_ I - I I I I I -1 +-1 I I I - I I I I ,~ IL-+ -I I T r ---j ROYAL PAR!f I HENDON N r - I L OM. STR':.f T _j_ ~ 7 :.. A _; [_ +- -- 1- -1 I - I _j 1- l ' I I I I [ - - I T I_ I I -, L I,- [] - - -1- r ~ L l ~•-« GIS18_0029 Figure 24 Former service station, Royal Park On and off-site environmental assessment commenced at the site in October 1990 as a result identification of petroleum hydrocarbons contamination in the soil during the removal of six underground fuel storage tanks. The underground storage tanks, lines and fuel bowers were excavated and removed in preparation for the decommissioning of service station and sale of the property. Concentrations of petroleum hydrocarbons were observed in soil and groundwater at above guideline values78. During a 1996 groundwater assessment, petroleum hydrocarbon, BTEX, arsenic and lead contamination were identified in a shallow or perched aquifer 2.5 to 3 m below ground water and in a deeper sand inter-layered aquifer located approximately 5.5 to 8 m below ground level 79 (Figure 25). In 1997 chlorinated hydrocarbons [TCE and 1,2 dichloroethane (DCA)] were also detected in the shallow groundwater. In addition to contamination detected in the shallow aquifer, widespread chlorinated hydrocarbons were also detected in the deeper aquifer80. Remediation commenced in 1997 utilising a high multi-phase vacuum extraction system to remove petroleum hydrocarbons from the soil and groundwater beneath the site. This system operated until 1999 and recovered over 3,000 L of petroleum hydrocarbon products from the soil and groundwater81. Rebound of contaminants were observed in several wells in 2001 with the presence of phase separated hydrocarbons. Continued observation of phase separated 78 BC Tonkin & Assoc 1991, Site contamination assessment investigation report, Royal Park, SA. 79 Rust PPK 1996, Initial site program. 80 Rust PPK 1997, Esso Royal Park Report – 3 March 1997. 81 Coffey Environments 2011, Detailed risk assessment former Esso Royal Park Service Station, 136–138 Tapleys Hill Road, Royal Park, SA. 33 Groundwater Prohibition Report – Hendon and environs hydrocarbons were noted in several wells, including a deep well, during both the 2006 and 2007 groundwater monitoring events82. ..."' Q "' BH 24l21 > .,,. < > .. < 11!9 0 A 1<. llktS S TRE ET L------~ ..,, !@ BH51 '------F AR HI<~ A VE IIHl6 ..a: BH53 0 w '-' Gr.a 10 .20 10 ~,r, St lwclwlWlwllwl ! SC>U 1:lOI» Deep Piezomater Plan - De ep Pinom@t er S C H O O l ESSO .. Royal Park ~ ... ,~o s et:1 Groundwater Monitoring Wella 1,-"'~'"~•- ~_c.__ _ Location Plan "' 2•~37 1-2 ?~/1/~6 i---+------1-- -. irl•Gi®t◄ "" Ulll•>th.'1'11 Figure 25 On and off-site groundwater investigation wells at service station, Royal Park83 An auditor was engaged in 2010 for the determination of nature and extent of site contamination, the suitability of the land for a sensitive use or other use and to determine what remediation is necessary. This audit is ongoing. In 2011 a detailed risk assessment was undertaken, including an historical and source investigation. The consultants estimated that the source release occurred more than 20 years ago and contaminants include petrol, diesel, heating oil, solvents and waste oil. During a detailed risk assessment, after the completion of active remediation on and off site, additional groundwater monitoring for natural attenuation parameters was undertaken. The consultants estimated that both the dissolved phase petroleum and chlorinated hydrocarbon plumes had migrated off site within the groundwater to an approximate distance of 70 m in an approximate southwesterly direction84. Continued monitoring has indicated that the petroleum hydrocarbon plume is stable, and probably contracting and degrading due natural attenuation processes85. The inferred groundwater flow direction for this site is in a southwesterly direction, which is not consistent with the regional flow direction (Figure 26). At this time the consultants have made no 82 Coffey Environments 2011, Detailed risk assessment former Esso Royal Park Service Station, 136–138 Tapleys Hill Road, Royal Park, SA. 83 Rust PPK 1996, Initial site program. 84 As above 85 Kleinfelder Australia 2015, Closure Request former Mobil Royal Park Service Station, 136–138 Tapleys Hill Road, Royal Park, South Australia 5014. 34 Groundwater Prohibition Area – Hendon and surrounds inferences for the altered groundwater flow direction and this may become resolved at the completion of the site contamination audit. An off-site vapour risk assessment undertaken in 2015 determined that a risk exists for residential properties with basements immediately adjacent and southwest of the site. There are no known basements adjacent to the former service station and the auditor engaged at the site may provide appropriate recommendations for off-site land use. , \ - ~ ,_, NOTE: ~ OCATION3 ~ E ~ROXIW.TE. \ Dlf.tEN3IONS IN t.tETREB. C.:.-.:111 ~.. Wrih l ·-- I ~ ~ INSrT DRTAILlll Sll'E LAYOUT ,uJrrt (ON.SITII) ·-- JIH! l\ \ G 16.12.1il DRA 133UE -G~ F 16.G4.1!1 ADOITION:AI.. I33UE G..~ E 12!!11/UI ANNl/"1. Gl.t E 13-S U-::. JR t »Q>- !MyA~SIM coffeyt, -(mt?lll:ll!lllJ en\lironments ,-,=.) .. n t - c..=- ,., .BRIS l -,,,,,,," 1/'n4 - ( ' fllff P..~'1111 - 1 l•llilolllol 11------7 I MOBIL Oil AUSTRALIA PTY LTD •••~" BIUJ \ t~~l 1 BHI ~ -- 8 11:tf ft .,ld,offr,I ~ ~ r.wri ,1 F,q,rt ': - - - ~f FORMER ESSO ROYAL PARK - (ORA) ·::::. r.. ~ ~,.~··_...._ ..._· __ 1---·-_·_.._ ·· _11· 1l6·1l9 TAPLEY"a- H:U. RONl ROY PARK, 30UTH ,'\IJ3TR - I lr S t•dldtol 9 I J ■ ,W.llol I DETAILED SITE LAJDUT PLAN I · ON l OFF-SITE I F\oll:ifrl.l (JU L1-1u;un 2010) I \ \ BHI ID 13 ONE INTER.;::RflATION ONl.Y OTI-IER ltfTERFRET.... Tl ON3AR£ P033 l6l.E.. -~lJI Figure 26 Off-site groundwater investigations and groundwater flow direction at service station, Royal Park86 3.4.7 Hendon Hotel, Royal Park (Figure 27) 110–120 Tapleys Hill Road, Royal Park Investigations commenced at the site as part of a due diligence assessment undertaken by consultants in 2003. A 2,200-litre capacity underground fuel oil storage tank was identified as a potential source of site contamination. Initial intrusive assessment identified petroleum hydrocarbons in soil surrounding the underground storage tank, situated northwest of the hotel building. With the installation of groundwater monitoring wells, phase separated heating fuel was identified in the groundwater, consistent with kerosene heating oil used on the site87 and believed to have been derived from the underground storage tank88 (Figure 28). Depth to water was identified at 3.5 metres below ground level for both a shallow water table aquifer 3.5–4.4 metres below ground level and a semi-confined deeper aquifer 5.5–7.5 metres below ground level89 (Figure 29). 86 Coffey Environments 2011, Detailed risk assessment former Esso Royal Park Service Station, 136–138 Tapleys Hill Road, Royal Park, SA. 87 SKM 2007, Hendon Hotel Remediation Project, Additional Environmental Assessment. 88 SKM 2004, Hendon Hotel Remediation Project, Environmental Investigation. 89 SKM 2012, Hendon Hotel, Detailed Risk Assessment. 35 Groundwater Prohibition Report – Hendon and environs I I I J r i- - Hendon Hotel 7 ~ l I lll\VIDSON "'/Ei'IUE J ,. Suburb ---j 1_-L j 1- - t - - _j ~ 1--=- i l -__j ,.-J i -j L L J r - [~ - -I I- - 1 J -- ] [_ - ~-J 1 r _I l J ; - 1_- 0 --l - I ~- r-_-1 - ~ J_ L _l I - I M\'fllL.t:STR':CT h- - 7 ~I I I I ~ 1-, l - I I r I l -I _ _L_ - J__ J_ I "~Hews~rr ~ -1 11 1 -1 j I =I- l 1 r -1- i- I I I - 7 I I I l -=:., -i ROYA!.. PARK I ~ I -J +--- ~ ENDON ~ N 7 _r- - 1 r -1 I I Ir l r A r _J -- I 7 L -1 soP"l'IITl1 1\\ll::f'li.J~ ~ I 7 + I \),lft,li;TREET I- r r 'I j_ j I- -+ I I . 7 I - - r 1-_ ~ I_ - - I . -, - r_ 1- I L I _I I r _I I -,--j- I - J - r ' I f J ~ [] ,r- l -J f-- 711 I I I I L T O:\ lo;STRE( l J t -, IILI ..__L - I F/\R-.,11\N ,',V~MUE t- - -; 1 l- 1 I - I C,.,0$..,... VW FI\I. --1- C_,.d .,_...... :r,-, I I r- -+ I -I I .,,, . +~ ...,,.,.,,c,-· ·corc I - ...,.,. c .. ,.,.., ...... r_ ,,.. - ,_ 1 I I i'o.i...,t~ I --1- I l- ---;-- I L '9,i,C' Figure 27 Location of Hendon Hotel 36 Groundwater Prohibition Area – Hendon and surrounds .0:,,,, G dWm,,· nmcing Wei ~ ♦ OHi!, ,e;rru d'lms· n·: : g -~ 0 Qi, &!I 5l!:ire· - · or ;;,= • - Figure 28 Groundwater monitoring wells and soil bore locations at Hendon Hotel90 90 SKM 2010, Additional Groundwater Investigations, Hendon Hotel, Hendon, SA. 37 Groundwater Prohibition Report – Hendon and environs WEST A B 0 0 a 0 0 0 0 0 a 0 0 0 0 0 a 0 0 0 0 0 0 0 0 0 a 0 0 0 0 0 0 0. 0 < 0 0, • 0 ''.'- ...... ' '.'' - ...... ' .. ''. . 6 ' ' ...... - .. ''·.·.·.·.·.·.·.· .... '' ...... ''.' .. . ·.· . .·.·.·.·.·.·.:.::: -·=. ~ANo . . ' ' ...... ' ...... ' .. 7 ...... '' ...... '' ...... '...... '...... - ...... ' .... . .· ·:::::::: , ••••• '.: '.::::: , •• '.:: ~, '.:: / '..:..,,. . .. ,!':·~ •j•~ ~-2~~~~~-~~--~- ~-~-~-- E--·~--~-··;-....:.,_;_~~~~i ~2~2gj::i:,,.,;.~~~:::~~~~:"'..,~:.:.:~M:v;•_T~~L~<~~s_T~:•~•~:•~T::~:::_~:~~:.::iai::;;:;Q 8 ...... --- - -. ~ ------. . ' . . . --- .MWII Q +S PT07 •-•---~ ~~ 26 9 MW I so.,,~ MNI 5R - -~-~·-~· B 10 ~. Fill g Clayey-Sand D Sand ~ Silty -Clay Clay Sandy-Clay "~ □ ~ 0 V Cement II Sand pack Screen □ $AM'16 MW1 7,$ Figure 29 East–west geological cross-section of Hendon Hotel91 The heating oil underground storage tank was installed during the construction of the hotel in 1963, and was located in close proximity to the foundations of the hotel’s northern external wall and covered in concrete pavement. During the initial years of assessment consultants considered that removal of the tank was not warranted as the tank was empty and no longer acted as a source of groundwater contamination92. Investigations in 2004, however, identified soil contamination in the ground surrounding the underground storage tank with phase separated hydrocarbons in groundwater over a large portion of the site. Due to contaminated groundwater mounding centred on the underground storage tank, it was deemed necessary to excavate the tank during a remediation program93 (Plate 3). The detection of an additional source of groundwater contamination, believed to be associated with an additional heating unit and associated piping, was identified immediately south of the hotel 94 (Figure 30). Chlorinated hydrocarbons were not analysed during any assessment phase at the site, although consultants identified a dry cleaning shop southwest of the site. The EPA holds no information regarding the use of that adjacent site as a dry cleaning facility. In 2007 remediation was undertaken at the site in the form of a multi-phase extraction air treatment system. During the remediation period 160 litres of petroleum hydrocarbons were removed and treated. The consultants consider that the full extent of the groundwater plume off site has not been determined. Numerical modelling was undertaken in 2010 which 91 SKM 2010, Additional Groundwater Investigations, Hendon Hotel, Hendon, SA. 92 SKM 2007, Hendon Hotel Remediation Project, Additional Environmental Assessment. 93 SKM 2004, Hendon Hotel Remediation Project, Environmental Investigation. 94 SKM 2010, Additional Groundwater Investigations, Hendon Hotel, Hendon, SA. 38 Groundwater Prohibition Area – Hendon and surrounds inferred that the groundwater plume has migrated approximately 50 m down hydraulic gradient from the site in a north- westerly direction95 (Figure 31). Groundwater contamination was assessed to be present in both the shallow water table and deeper semi-confined aquifers. The consultants have recommended that groundwater should not be extracted or used as a source of drinking water, irrigation or any other beneficial use96. With continuing investigation at the site, the consultants have considered that with good indications of natural attenuation conditions, degradation of the petroleum hydrocarbons will reduce the contamination plume further at an acceptable rate97. --- ., Figure 30 Petroleum hydrocarbon groundwater plume at Hendon Hotel98 95 SKM 2010, Additional Groundwater Investigations, Hendon Hotel, Hendon, SA. 96 SKM 2007, Hendon Hotel Remediation Project, Remediation Action Plan. 97 Jacobs 2015, 2015 Groundwater Monitoring Event – Hendon Hotel. 98 SKM 2010, Additional Groundwater Investigations, Hendon Hotel, Hendon, SA. 39 Groundwater Prohibition Report – Hendon and environs ... • ElllstlngC.rnmctwaterll ♦ Sll,aJIDWGroutdWaterMonloMgW6 .. DeepGlotlrtCNiaterl.lai:toMgiW~ -- lrtt.;aJpre-...CI GllJU'li,,1•.aterCOnX11A (mAHOJ -- lrll'erredGrtUld'.ralHColttOln (IMHO) --+ lm'erredGllU!d'Ma!H Flr:NtDln!c:on Figure 31 Groundwater flow direction in the water table and semi-confined aquifers at Hendon Hotel99 3.4.8 Former electroplating facility, Hendon (Figure 32) 53–59, 67–69 Tapleys Hill Road; 4, 12 and Lot 100 Florence Street, Hendon Investigations commenced at the former electroplating facility in 1996 with a site history review to identify the need for a preliminary site investigation. The site was originally part of a larger site which undertook industrial activities, including electroplating 100. During the preliminary site investigation it was identified that the site probably caused site contamination through historical electroplating practices. In 1997 soil investigation commenced at the property and site contamination was identified 101. Further intrusive soil investigation were undertaken in 2010 with the identification of on-site heavy metals and arsenic102. The presence of petroleum hydrocarbons, heavy metals, cyanide, arsenic and chlorinated hydrocarbons were identified in groundwater during a further site assessment in 2015103. Groundwater, gauged at approximately 3.2 m below ground level, in the unconfined water table aquifer flows in a northwest direction, which is consistent with the regional groundwater flow direction (Figure 33). 99 SKM 2010, Additional Groundwater Investigations, Hendon Hotel, Hendon, SA. 100 FMG Engineering 2010, Environmental Soil Contamination Assessment, 61 Tapleys Hill Rd, Hendon. 101 Woodward–Clyde 1997, Phase II Soil Investigation of TRW Carr Site, Hendon. 102 FMG Engineering 2010, Environmental Soil Contamination Assessment, 61 Tapleys Hill Rd, Hendon. 103 URS 2015, Phase 2B Environmental Site Assessment, Hendon Self Storage. 40 Groundwater Prohibition Area – Hendon and surrounds QUEENSTOWN Electroplating - Facility N 1 • • • EPA Groundwater 11,, ••• Prohibition Area 0 100 A I • Suburb -- -Metres Government . of south Ausm1ha G!S18_0029 Figure 32 Former electroplating site, Hendon 41 Groundwater Prohibition Report – Hendon and environs M:JISTIAN HE DO SELF SlORAGE INFERRED GROUNDWATER PROPERTY TAPLEYS HIU ROAD, HEN DON, SA TRUSTS CONTO URS (mA HDJ Figure 33 Inferred groundwater flow direction from former electroplating site, Hendon104 At this time no off-site assessment had been undertaken in the vicinity of the site and it was considered that site contamination arising from this site had potentially contributed contamination to the northwest of the site. The EPA is continuing to regulate the liable party to complete off-site assessment to determine the extent of contamination in the vicinity of the site. A conservative one-dimensional numerical model was applied to the site utilising known information and inferred data to estimate the groundwater plume extent. Additional assessment would be appropriate to confirm modelled plume extent (Figure 1). 3.4.9 Queensbury Wastewater Pumping Station, Hendon (Figure 34) Corner of Davidson Avenue and De Haviland Avenue, Hendon Investigations commenced at the site in 2012 as part of a due diligence assessment undertaken during an upgrade of the pumping station. Groundwater monitoring detected contamination derived from associated sewage activities in the form of metals, nitrogen and E coli 105. The EPA is continuing to regulate the site while further assessment is undertaken to monitoring the attenuation of chemicals within the groundwater. 104 URS 2015, Phase 2B Environmental Site Assessment, Hendon Self Storage. 105 Aurecon 2012, Queensbury Pumping Station, letter report – environmental site assessment, Hendon. 42 Groundwater Prohibition Area – Hendon and surrounds STACY STREET -1 T 1- 7 L - ,----- I I I I I J__ j 1 I I I 11 --1 - -I I j ~ I _JI I l-7 r 1' I I_ --1 I ~- j ~ 1, - I r-I ,-1-l i--- I---; I I I I _l__ _I _J_ DAVIDSON AVENUE -, -----; I I r-1 I I I l_ ~T ---7' I I I \ I I I I _I L VICKERS AVENUE r-T s' 1- I I I l 1 ~J_-i - I - , ,- -7 I I I 1 I I I I I I I I I _J I I I - " I I I I I _J \ - ~ ~-l _L --, I~ L_ l__ ANDREW STREET ,-T r ,--- - -7 I I I I I - 1 I I ___ i _l_~l Producedb)'K11CM'k;,dg<:l,lnlorril!ltion &Sl1at~y Emrironm9nt Prot.ictionAUlh::lrity GPO Box 2607AdclaidoSA5001 1 • • • EPA Groundwater www.epa.sa.gov.au Oat.-.Source DEW.EPA ■ •• -■ Prohibition Area Compih:d 20Augu:;l2019 Projection Lombcrt Conformal Conic Datum Geocentric Datum ol Austnlll11. 1994 - Queensbury Pump Station ~ ...... cnft - 0.<0 ...- .. A 50 Government Metres o f Sout hAuitralla G!S18_0029 Figure 34 Queensbury Wastewater Pumping Station, Hendon 43 Groundwater Prohibition Report – Hendon and environs 3.4.10 Former tin can production and car assembly site, Albert Park (Figure 35) 24–30 Murray Street, Albert Park An initial site history and assessment was undertaken in 1997 and a preliminary site investigation was completed in 1998. The site was identified as a tin can production facility from 1940 to 1984106. During the 1998 investigations, samples from soil bores were analysed reporting contaminants of concern in the form of heavy metals. A more detailed site history investigation was undertaken in 2013 where consultants identified items on site associated with solvent and fuel storage infrastructure. The consultants suggested that underground and above ground storage tanks may have been utilised at the site. While consultants were unable to identify evidence of above ground fuel storage tanks on the site107, planned investigations in 2018 and 2019 identified potential sources contributing to site contamination at the site (Figure 36). A detailed site investigation, undertaken in 2018, identified chlorinated hydrocarbon concentrations in groundwater above World Health Organization drinking water guidelines108. The groundwater contamination was believed to have arisen from contaminating activities associated with the tin can manufacturing processes, such as degreasing of machinery and electroplating finishing of the final product. The extent of the groundwater contamination has not been delineated, however, the consultants have determined that a groundwater plume arising from the site is moving in a northwest direction109 (Figure 37). A site contamination auditor has been engaged to audit the site to give consideration to the nature and extent of onsite contamination, the site suitability for a sensitive use, and to consider the necessary remediation. A conservative one-dimensional numerical model was applied to the site utilising known information and inferred data to estimate the groundwater plume extent. Additional assessment would be appropriate to confirm modelled plume extent (Figure 1). 106 Land and Water Consulting 2018, Detailed Site Investigation, 24–30 Murray Street, Albert Park, SA. 107 As above 108 WHO 2017, Guidelines for drinking water quality, fourth edition, World Health Organization, Geneva, http://www.who.int/water_sanitation_health/publications/2011/dwq_guidelines/en/. 109 Land and Water Consulting 2018, Detailed Site Investigation, 24–30 Murray Street, Albert Park, SA. 44 Groundwater Prohibition Area – Hendon and surrounds L ~· -- Jt t ~----, 1 ~ 1 -- ~ t =- ~ r I - CHELTENHAM - I i--1 17 --< L__ l L _J_ J MALIN STREET r -,I -I I_ I I __ j I t I L,- l r- I I- L I I -1 1-- L r -- i __ l -- ~ I I I r-- _I I I I I I +-- L-- j 1 - j I I I I _l l 1- ~-L 1-- --~ 1 l- --r l-- I I r 1 __ l_ I_ I 1 SPENCE STREET ---, l -1- r-- ~ - I f 7 +- ALBERT PARK i j _) -!- I GRACE STREET - ---+ j I r I t -7 i- I J__--1 I ~ ,- _ _, OS BORNE STREET l i L _j I ~- I I I j I I -1 11- , l - I 11_~ I I ~ --j I~ -,7 -j r- r t- ~ - l ----j : ~=- _1-, - +- ~ 1 1 1 : 1- -- --, ,~-I I ---t -7- --+ -t- 1- ' J I f- ~--r-- I --+ - f--- r- --t j I - 1- -1 r r --1 -, _;::r -ir - i 1 +--, r I _J_ - [ - -7 1 -- --< NESBIT STREET ---, 1 ,-- [ I I I r -- --~ i i i- - 1 ~ -- PrQduced by Know !t>dp~, lnforrnalion & Sha!~y 1 • • • EPA Groundwater EnvirOllffi9nT Pmt.ictionAUlharity GPO Box 2607AdclaidoSA5001 ■ • • ,!, Prohibition Area www.epa.sa.gov.au N DntaSource DEW, EPA C,;,mpihi:d 20Augu:;l2019 - Former Tin Can Facility Proj,ction Lambcn Conformal Conic Datum Geocentric Datum ol Australia. 1994 ~ <.o:,,1c-. IOI L""'""'""'' ~10,,,:...,., ,.._.., .., Y l Government of South Australia South AU$tr•li.i GIS18_0029 Figure 35 Former tin can facility, Albert Park 45 Groundwater Prohibition Report – Hendon and environs ...... D "'· ••P-.------·-·-·-· WC _.._,_ 2'dl!I qp,n 1-----=-'- -, 2 Figure 36 Site features of former tin can facility, Albert Park110 -······ ~-~-£~ ••.AHO ) ----+ ..,....,i:.-...--Rt.~-"" WC 6a 110 Land and Water Consulting 2018, Detailed Site Investigation, 24–30 Murray Street, Albert Park, SA. 46 Groundwater Prohibition Area – Hendon and surrounds Figure 37 Interpreted groundwater flow direction and reported TCE concentrations at Albert Park111 111 Land and Water Consulting 2018, Detailed Site Investigation, 24–30 Murray Street, Albert Park, SA. 47 Groundwater Prohibition Report – Hendon and environs 3.4.11 Former tannery site, Albert Park (Figure 38) Hawkes Street and Gordon Street, Albert Park (5–7 Hawkes Street and 10–16 Gordon Street) Initial assessment of the site was undertaken in 1988 with the identification of arsenic concentrations in soil. In 1989, groundwater assessment was undertaken on the western portion of the site to determine the shallow groundwater arsenic contamination on site. Groundwater sampling, however, did not identify arsenic within the water table aquifer112. A conservative one-dimensional numerical model was applied to the site utilising known information and inferred data to estimate the groundwater plume extent. Additional assessment would be appropriate to confirm modelled plume extent (Figure 1). 112 AGC 1989, SA Housing Trust Hydrogeological Investigation of Albert Park Site. 48 Groundwater Prohibition Area – Hendon and surrounds I~ I ' I I ' I I I I QUEENSTOWN I I I I -1 L CHELTENHAM I I -1 I ~ r J I I I I ( I I I r- ~ I I I 1 I 1 I - +- _J I ---r I I f I I 1 I r-- I _j I ALBERT PARK I I 1 I I I I -- -- I j I I I ~ I I I ~- f- 7 _j r I I I I I I a-- I- -j I I 7 I I ,~ j -+- ~J I f- - ~ I I ~- I I I r -1 T- I _j_ r- I I j I -i ,-- r-- - 1 I 1 1 I I ' I I __ _J -7 I - _J_ I_ I DERBY STREET I ,--- - LAWRENCE STREET I i -T I - _, PrQduced by Know !t>dp~, lnforrnalion & Sha!~y ■ ■ ■ ■ EPA Groundwater EnvirOllffi9nT Pmt.ictionAUlharity GPO Box 2607Adclaido SA5001 ■ ■ ■ : Prohibition Area www.epa.sa.gov.au DntaSource DEW, EPA C,;,mpihi:d 20Augu:;l2019 - Former Tannery Proj,ction Lambcn Conformal Conic N Datum Geocentric Datum ol Australia. 1994 ;;><.o:,,1c-._10r L""'""'""'' ~'°"'"-""''.._.., .., Yl Government of South Australia GIS18_0029 Figure 38 Former tannery, Albert Park 49 Groundwater Prohibition Report – Hendon and environs 3.4.12 Former light industrial site and tow truck operating site, Albert Park (Figure 39) 51 Glyde Street and 40 Murray Street, Albert Park The South Australian Health Commission (SAHC) investigated the site in 1991 as a result of a proposed site development to a more sensitive use. Soil contamination of heavy metals, specifically lead, and petroleum hydrocarbons was identified. The SAHC determined that groundwater testing was not required113. The assessment report recommended excavation and removal of contaminated soil, development of planting and groundcover of unsealed areas to further reduce contact with surface soil114. - -1 - Former Tow Truck Site - __j - - •• • • 1 EPA Groundwater L_ r I- , • • .• Prohibition Area -I j L L - Suburb OSEIO\( Nf. $ TAt£T - ,--- - 1- T - r - l j 1- r -1 r _J T I -, - ~ j j - -i I 1- I_ t - J ~ - --j- - 7 t; ~- :ALBERT PARK I ~ L -- N -1 ~ -, I L... A "I Ntc$EIITSTRl:.ET - r -- (_ I r - n I r- -- I 7 -1 - -- r - I LJ 7 I -- f ~.OK«IW ~- 1'•'' c<'1". ¼ b'I'! -( l .;~t ' • ,~ ".:',- :.,.;.,':'D - ;$>...,v! C GIS18_0029 Figure 39 Former tow truck operator site, Albert Park 3.4.13 Former orchard and mixed manufacturing, Royal Park (Figure 40) 3 Dover Street, Royal Park In 2007, with the intention to develop the site for a sensitive use, an auditor was engaged to complete a site audit. Investigations commenced with a two-phase environmental site assessment. Heavy metal contamination in soils was identified at the site during the initial assessment phase, however groundwater was determined not to be impacted by onsite contamination.115 The auditor concluded that soils at the site do not pose an unacceptable human health risk, providing the proposed residential development restricted the access to these soils. The auditor considered that levels of nitrate and fluoride in 113 SAHC 1991, South Australian Health Commission Report, Albert Park Project No. 43-12-01-01. 114 As above 115 Hall A 2008, Site Audit Report, 3 Dover Street, Royal Park. 50 Groundwater Prohibition Area – Hendon and surrounds the groundwater, potentially from an off-site source, precluded the extraction of groundwater for potable or irrigation use without testing 116. ~ .. ..j J I - ~°::~~~~~ng l. -I L_ - -I 1- m.JMSTR!:lc.T 1• • • • EPA Groundwater I -S 7 11 • • .• Prohibition Area Suburb 7 HENRYSi REH I- ' i l i- -+- I I -I I r--- - I I 7 I I L w I 1- i L - -r ~ f- i -1 I ~ -I- 1 I t 7 i- I- -I -I L N I r ..J ' A r - I - r- j _J -- -1 ___L I - ..J (lf. Ol!CESTl I_ i ~od0 GIS18_0029 Figure 40 Former orchard and mixed manufacturing, Royal Park 3.4.13 Former vacant land, Royal Park (Figure 41) 12 George Street, 7–10 Dover Street and 3A Royal Terrace, Royal Park The SAHC undertook an assessment in 1992 for a proposed residential development. Soil investigation did not identify contamination in the fill material, and the site was considered suitable for the proposed residential development. A groundwater investigation was not undertaken117. 116 Hall A 2008, 3 Dover Street, Royal Park, Site Audit. 117 SAHC 1992, Lot 289 Royal Terrace, Lot 4 George Street & Lots 267, 268, 269, 270 & 271 Dover Street, Royal Park. 51 Groundwater Prohibition Report – Hendon and environs I . - Former Vacant Land I 1• ■ • I EPA Groundwater - • • ■ .• Prohibition Area I . L • I . I I_ H':'IR~STRf l:l' +- I I- l_ --r _J I l t--- -1 L I f I I T ~ I i i .• L N I . 0 l A . f _J I --- I . _J ;- -1 T TI I_ 1- 7 I I I - -1 l l _I i _L L L - ·······1 - 7 ;. 17 7 "~ ' I ~ GIS18_0029 Figure 41 Former vacant land, Royal Park 3.5 Groundwater users Within the GPA (incorporating portions of Hendon, Royal Park, Seaton and Albert Park) there are 182 registered groundwater wells. Of those wells; • 10 are registered as domestic accessing the water table or first Quaternary aquifer • 21 are registered as domestic accessing the second Quaternary aquifer • 6 are registered as domestic accessing the third Quaternary aquifer • 4 are registered as domestic accessing the deeper Quaternary aquifers • 9 are registered as irrigation and industrial accessing the first Tertiary aquifer • 132 are registered as monitoring wells. The groundwater within the Quaternary aquifers, generally contains between 700 mg/L and 9,000 mg/L total dissolved solids and has an average extraction yield of 1.5 L per second. The groundwater is considered potentially suitable as a domestic water and domestic irrigation supply. Groundwater in this area is known to be used for gardening (including water for home-grown produce), irrigation of lawn, filling of swimming pools and grey water use (eg toilet flushing). 3.6 Factors considered in the determination of the groundwater prohibition area 3.6.1 Buffer zone The determination for the necessity of a GPA can incorporated both the measured groundwater plume footprint and a potential conservative plume expansion area, known as a ‘buffer zone’. Incorporating a buffer zone into a GPA will also prevent further expansion of the groundwater plume through groundwater abstraction at a rate higher than the natural groundwater flow. 52 Groundwater Prohibition Area – Hendon and surrounds The GPA includes the known sources sites and surrounding properties within portions of the suburbs of Hendon, Royal Park, Seaton and Albert Park. The majority of the properties are residential and down hydraulic gradient to one or more of the source sites. The buffer area extends beyond the known and inferred groundwater plume extents where numerical modelling and monitoring has identified 10% of EPA recognised drinking water criteria118 at the leading edge of the groundwater plumes. The buffer area is incorporated into the GPA to prevent expansion of the plume due to groundwater extraction, and to allow for variations in model calibrations. 3.6.2 Numerical modelling The estimated final extent of the frontal position of the groundwater plumes in the GPA was determined by direct measurement and with the assistance of fate and transport numerical modelling. Aquifer well testing can give measured value for hydraulic conductivity which is utilised to calculate groundwater flow velocity. It is important to note that the heterogeneity of the sedimentary aquifer within the Adelaide Plains can produce uncertainty in the aquifer parameter values calculated. For example the frontal position of a groundwater plume, moving over a 50-year period, may vary from the calculated position. A contaminant fate and transport numerical model for the Hendon industrial area was used primarily to simulate contaminant transport of the groundwater plume, down hydraulic gradient. The objective of the modelling was to estimate the stability of the groundwater plume. The groundwater monitoring results were modelled to identify the fate and transport of contaminants within the unconfined first Quaternary aquifer from the Hendon industrial area. The modelling predicted a zero boundary groundwater plume to be approximately 500 m from the source, northwest beneath residential properties119. Due to the ongoing investigations in the north-eastern portion of the Hendon industrial area, calibration and re-simulation of the model is necessary after the completion the final assessment. Recalibration of the modelling and statistical analysis would indicate the final projected extent of the groundwater plume and determine when the plume approached steady state or the finite maximum length of the plume. The buffer zone incorporates the current conservative projected modelled extent. A conservative one-dimensional numerical model was applied to additional sites utilising known information and inferred data to estimate the groundwater plume extents. 3.7 Exposure pathways and human health risk assessment The risk to human health and safety predicted by the presence of contaminated groundwater is determined by investigating the source–pathway–receptor linkages. This process determines what risk is created by the presence of contaminants of concern by determining if there are pathways through which these contaminants can impact sensitive receptors. 3.7.1 Vapour intrusion The assessment of the volatile contaminants of concern comprising chlorinated hydrocarbons and petroleum hydrocarbons remains ongoing at a number of locations within the GPA, as discussed in section 2. 3.7.2 Groundwater abstraction The movement of contaminants within the groundwater through advection, diffusion, dispersion and chemical reactions from a site to an abstraction well, creates a valid groundwater pathway from source to receptor. The risk to human health and safety exists from the exposure to dissolved and phase separated (LNAPL) contaminants within the groundwater and use of that groundwater by the receptor. 118 EPA 2018, Guidelines for the assessment and remediation of site contamination 119 Greencap 2017, Hendon Broader Assessment Area (Stage 3), Hendon, SA. 53 Groundwater Prohibition Report – Hendon and environs 4 GPA consideration To reduce or prevent human exposure to contamination from former industrial land uses, the EPA is able to use the provision of section 103S of the EP Act to prohibit or restrict access to groundwater by establishing a GPA. The GPA can provide interim protection while the contaminants of concern naturally attenuate within the groundwater or a remediation strategy is determined. To meet the legislative requirements to establish a GPA, the EPA requires information that documents the existence of site contamination, the nature of groundwater contamination, and the lateral and vertical extent of groundwater contamination. The environmental assessment reports, held by the EPA (Appendix 3) describe the site contamination at a point-in-time within portions of Hendon, Royal Park, Seaton and Albert Park. The GPA includes the known lateral and vertical extent of the groundwater contamination, and a buffer zone surrounding the groundwater contamination. The buffer zone is an important part of the GPA, as it is designed to prevent the groundwater plume from expanding due to groundwater extraction from currently installed nearby wells. Contaminants in deeper aquifers are characterised in isolated areas, indicating that chemical substances have the potential to migrate vertically downward through lithology via gravity driven processes. This migration may result from a hydraulic head pressure which is likely to have arisen from aquifer recharge via garden irrigation, localised stormwater pooling acting on preferential pathways, gravitational flow into deep sewer lines or gravitational migration of non-aqueous liquid phase contaminants. Unconfined aquifer recharge of this type is likely to cause a transient downward migration of the higher density, lower viscosity chemicals. The down vertical migration of contaminated groundwater is likely to impact the deeper semi-confined second Quaternary aquifer and possibly the third and fourth Quaternary aquifers. Groundwater monitoring wells have identified contamination in the lateral extensions of various groundwater plumes in the GPA. The widths of groundwater plumes are generally larger relative to the width of the source areas. This may be attributed to natural contaminant movement within the aquifer and periods of lateral flow due to seasonal changes and changes in hydraulic head of the water table during periods of domestic irrigation above the unconfined aquifer. By using the preliminary data available, an estimated final plume extent can by predicted and the margins of the GPA, that incorporates both a measurable groundwater plume and a potential conservative plume expansion area, can be determined. Incorporating these margins as a buffer zone aims to prevent further expansion of the groundwater plume through groundwater extraction at a rate higher than the natural groundwater flow. The GPA includes the source sites (see section 2.6) and portions of the surrounding suburbs in a west and northwest direction. The majority of the properties in the GPA are down groundwater hydraulic gradient to the source sites. The buffer zone extends to 10% of EPA recognised drinking water criteria120 at the leading edge of the groundwater plumes. This is to allow for variations in model calibrations and to prevent expansion of the plume due to groundwater extraction. The GPA includes the first and second Quaternary aquifer for approximately 1.5 km from May Street, Albert Park. 120 EPA 2018, Guidelines for the assessment and remediation of site contamination 54 Groundwater Prohibition Area – Hendon and surrounds 5 Community information 5.1 Community engagement The EPA has been continually engaging with residents in portions of the Hendon, Royal Park, Seaton and Albert Park area since 2012, through various methods of communication. All letters and fact sheets are available on the EPA website. In August 2019, the EPA concluded a 90-day community engagement program to discuss its proposal to establish a GPA with the community. Information regarding community engagement is detailed in Appendix 6. 5.2 Access to EPA information On 12 September 2019 the will establish a GPA as it has been determined that there is site contamination that affects or threatens water, and that action is necessary to prevent actual or potential harm to human health or safety. As a result, the EPA will place a notice in the Government Gazette that prohibits the taking of water. The notice specifies the water to which it relates; and give particulars of the site contamination affection the water. The EPA will establish a Groundwater Prohibition Area pursuant to section 103S of the Act, and details of the GPA will be placed in the EPA public register121. It is important that all current and future owners of properties within a GPA area are made aware of the prohibition. The EPA cannot notate the existence of a GPA on the Certificate of Title. Notice will be given to potential purchasers of the land on the Form 1 via Section 7 of the Land and Business (Sales and Conveyancing) Act 1994. This provides an ongoing method of ensuring potential and future owners are aware of a statutory prohibition. 121 Pursuant to section 109 of the EP Act 55 Groundwater Prohibition Report – Hendon and environs 6 Conclusion The EPA will establish a GPA in portions of Hendon, Royal Park, Seaton, Albert Park pursuant to the provisions of section 103S of the EP Act. This report review the circumstances and information which has given rise to the recommendation to establish a GPA. This action will prohibit the taking of groundwater within the designated area. The GPA includes the first and second Quaternary aquifer for approximately 1.5 km in a north-westerly direction from May Street, Albert Park (Figure 1). Future purchasers of properties within the GPA will be made aware of the prohibition on taking of groundwater via the Form 1 Statement pursuant to Section 7 of the Land and Business (Sale and Conveyancing) Act 1994. Following the establishment of a GPA, it is an offence to use groundwater for any purpose, other than for environmental monitoring, in the prohibition area. A maximum penalty of $8,000122 applies (Division 4 fine). 122 At the time of publication 56 Groundwater Prohibition Area – Hendon and surrounds 7 Glossary aquifer Rock or sediment in a formation, group of formations, or part of a formation which is saturated and sufficiently permeable to transmit water. attenuation Reactions that cause contaminant concentrations to decrease in surface or groundwater. audit Refer to environmental site audit and site contamination audit auditor Refer to environmental site auditor and site contamination auditor background In relation to chemical substances on a site or below its surface, results obtained from concentration carrying out assessments of the presence of the substances in the vicinity of the site in accordance with guidelines from time to time issued by the EPA. Refer to the EPA publication, Site contamination: Assessment of background concentrations. chemical Any organic or inorganic substance, whether a solid, liquid or gas (or combination thereof), and substances includes waste. environmental A detailed written report that − audit report (a) sets out the findings of the audit and complies with the guidelines and standards (in particular, the Environmental Auditor Guidelines for issue of certificates and statements of environmental audit) issued by the Victorian EPA; and (b) includes the issue of either a certificate of environmental audit or statement of environmental audit, in the prescribed form, by the environmental auditor who personally carried out or directly supervised the audit. environmental A person accredited under the Victorian Environment Protection Act 1970 as an environmental auditor auditor. Since 1 July 2009 South Australia has accredited persons who undertake site contamination audits in the state. groundwater Water held in the pores of an aquifer. groundwater Site contamination of underground water. Refer to EPA publication, Site contamination: contamination Guidelines for the assessment and remediation of site contamination groundwater A mixture of chemicals and groundwater, usually in soluble form. contaminant plume groundwater The establishment by the EPA under section 103S of the EP Act. prohibition area hydraulic Rate of water movement through an aquifer. conductivity hydraulic head Specific measurement of water pressure within an aquifer. hydraulic Measurement of an aquifer’s capacity to transmit water. transmissivity land Land as a physical entity, including land covered by water. potentially An activity prescribed in regulation 5 of the Environment Protection (Site Contamination) contaminating Regulations 2009. activity remediate To remediate a site means treat, contain, remove or manage chemical substances on or below the surface of the site as to − (a) eliminate or prevent actual or potential harm to the health or safety of human beings that is not trivial, taking into account current or proposed land uses; and 57 Groundwater Prohibition Report – Hendon and environs (b) eliminate or prevent, as far as reasonably practicable − (i) actual or potential harm to water that is not trivial; and (ii) any other actual or potential environmental harm that is not trivial, taking into account current or proposed land uses. remediation Has the same meaning as remediate. site An area of land (whether or not in the same ownership or occupation) site contamination Exists at a site if – (a) chemical substances are present on or below the surface of the site in concentrations above the background concentration (if any); and (b) the chemical substances have, at least in part, come to be present there as a result of an activity at the site or elsewhere; and (c) the presence of the chemical substances in those concentration has resulted in − (i) actual or potential harm to the health or safety of human beings that is not trivial taking into account current or proposed land uses; or (ii) actual or potential harm to water that is not trivial; or (iii) other actual or potential environmental harm that is not trivial, taking into account current or proposed land uses. site A detailed written report that− contamination (a) sets out the findings of the audit and complies with the guidelines from time to time issued by audit report the EPA; and (SCAR) (b) includes a summary of the findings of the audit certified, in the prescribed form, by the site contamination auditor who personally carried out or directly supervised the audit. site contamination A person accredited under Division 4 of Part 10A of the Environment Protection Act 1993 as a site auditor contamination auditor. site contamination A person other than a site contamination auditor who, for fee or reward, assesses the existence or consultant nature or extent of site contamination steady state The ongoing migration of contaminants from the source and within the plume is match by the overall rate of attenuation. stratigraphy Vertical sequence of geological units. total dissolved Dissociated compounds and un-dissociated compounds, but not solids (TDS) suspended material, colloids or dissolved gases. water (a) water occurring naturally above or under the ground; or (b) water introduced to an aquifer or other area under the ground; or (c) an artificially created body of water or stream that is for public use or enjoyment. water table Interface between the saturated zone and unsaturated zones. The surface in an aquifer at which pore water pressure is equal to atmospheric pressure. 58 Groundwater Prohibition Area – Hendon and surrounds Appendix 1 Summary of penalties and fees Table A1–1 Section 103S Section 103S – Prohibition or restriction on taking water affected by site contamination (1) If the Authority is satisfied that – (a) there is site contamination that affects or threatens water; and (b) action is necessary under this section to prevent actual or potential harm to human health or safety, the Authority may, by notice in the Gazette, prohibit or restrict the taking of the water. (2) A notice under this section must – (a) specify the water to which it relates; and (b) give particulars of the site contamination affecting the water. (3) A person must not contravene a notice under this section. Penalty: Division 5 fine. (4) The Authority may, by notice in the Gazette, vary or revoke a notice under this section. Penalties There are a number of offences (and associated expiation fees and penalties) provided for in the Environment Protection Act 1993. A summary of the consequences for relevant division penalties is shown in the following table. Table A1−2 Summary of relevant division penalties Division Maximum imprisonment Maximum fine Expiation fee 1 15 years $60,000 − 2 10 years $40,000 − 3 7 years $30,000 − 4 4 years $15,000 − 5 2 years $8,000 − 6 1 year $4,000 $300 7 6 months $2,000 $200 8 3 months $1,000 $150 9 − $500 $100 10 − $200 $75 11 − $100 $50 12 − $50 $25 59 Groundwater Prohibition Report – Hendon and environs Appendix 2 Source site details Source site addresses and Certificates of Titles or CTs (based on the extent of the site at the time the investigations were undertaken) within Local Government areas. Source sites: Hendon industrial area, Hendon, City of Charles Sturt 3–5 Philips Crescent, Hendon (CT 2187/124, 2270/14, 5056/319, 5227/729, 5227/730, 5227/732, 5227/754, 5264/952, 5848/524, 6141/660 and 6146/661). 10, 12, 13, 15, 17, 24 and 31 Circuit Drive, Hendon (CT 5252/447, 5288/897, 5291/664, 5374/619, 5685/714, 5708/656 and 6150/533). Service station, Seaton, City of Charles Sturt 169–171 Tapley Hill Road, Seaton (6081/183) Former market garden, Seaton, City of Charles Sturt 187 and 193 Tapleys Hill Road, Seaton (CT 6060/379 and 6060/380) Vehicle storage and maintenance site (former service station), Royal Park, City of Charles Sturt 162–168 Tapleys Hill Road, Royal Park (CT 5731/348 and 5987/374) Commercial building (restaurant and hairdresser), Royal Park, City of Charles Sturt 150–152 Tapleys Hill Road, Royal Park (CT 6188/259, 6188/260, 6188/261, 6188/262, 6188/263, 6188/264, 6188/265, 6188/266, 6188/267, 6188/268, 6188/269, 6188/270 and 6188/271) Former service station, Royal Park, City of Charles Sturt 136–138 Tapleys Hill Road, Royal Park (CT 5229/371, 5229/372 and 5229/373) Hendon Hotel, Royal Park, City of Charles Sturt 120 Tapleys Hill Road, Royal Park (CT 5140/827 and 5616/742) Former manufacturing and electroplating facility, Hendon, City of Charles Sturt 53–59, 67–69 Tapleys Hill Road, Hendon (CT 5219/606, 5559/570, 5559/571, 5559/572, 5559/573, 5559/574, 5559/575, 5602/286, 6059/686, 6059/687, 6059/688, 6059/689, 6059/690, 6076/959, 6076/960, 6078/141, 6084/779, 6084/780, 6084/781 and 6084/782) Queensbury pump station, Hendon, City of Charles Sturt Lot 2 Tapleys Hill Road, Hendon (CT 6144/150 and 6144/151) Former tin can manufacturing facility, Albert Park, City of Charles Sturt 24 Murray Street, Albert Park (CT 5191/397, 5191/507, 5957/139, 5957/140 and 5957/141) Former Albert Park tannery, Albert Park, City of Charles Sturt Gordon and Hawke Streets, Albert Park (CT 5392/776, 5392/803, 5392/993, 5392/994, 5392/995, 5392/996, 5392/997, 5392/998, 5392/999 and 5392/1) Former tow truck operator, Albert Park, City of Charles Sturt Lot 264 Glyde Street; Lots 261 & 263 Murray Street; 51 & 40 Glyde and Murray Streets (CT 5118/205 and 5118/206) Former orchard and mixed manufacturing, Royal Park, City of Charles Sturt 3 Dover Street, Royal Park (CT 6056/392 and 6056/393) Former bushland, Royal Park, City of Charles Sturt Lot 267 George Street Royal Park (CT 5116/440, 5116/624, 5116/626, 5116/627, 5116/628 and 5723/849) 60 Groundwater Prohibition Area – Hendon and surrounds Appendix 3 Details of reports available in the EPA Public Register Table A3–2 EPA information sources recorded in the EPA Public Register − Hendon industrial area EPA EPA file Report name Author Report date reference type Hendon Industrial Area 10645 S109 Environmental Site Assessment – Delen Coffey Partners 6 Aug 1992 Corporation site, 3–5 Philips Crescent, Hendon; International Vol 1 10645 S109 Environmental Site Assessment – Delen Coffey Partners 6 Aug 1992 Corporation site, 3–5 Philips Crescent, Hendon; International Vol 2 10645 S109 Environmental Site Assessment and Site Coffey Partners 31 Oct 1992 Remediation – Second Stage; Delen Corporation International site, 3–5 Philips Crescent, Hendon; Vol 1 10645 S109 Environmental Site Assessment and Site Coffey Partners 31 Oct 1992 Remediation – Second Stage; Delen Corporation International site, 3–5 Philips Crescent, Hendon; Vol 2 10645 S109 Soil Vapour Monitoring Event – Results of soil Coffey Partners 15 Dec 1992 gas survey and preliminary costing of selected International site remediation options, 3–5 Philips Crescent, Hendon 60624 EPA Ass Environmental Site Assessment – Hendon Parsons Brinkerhoff 22 Mar 2013 60624 EPA Ass Environmental Site Assessment – Additional Parsons Brinkerhoff 30 Oct 2013 Site Assessment, Hendon 60624 EPA Ass Environmental Site Assessment – Additional Parsons Brinkerhoff 16 Jun 2014 Site Assessment, Hendon 60624 EPA Ass Soil Vapour Monitoring Event – Soil Vapour CH2MHill 4 Feb 2015 Assessment Report, Delineation of Soil Vapour Contamination Around SB10 60624 EPA Ass Vapour Risk Assessment – Human Health Risk CH2Hill 6 Mar 2015 Assessment for Vapour Impacts in the Vicinity of SV10, Hendon Industrial Area, Hendon 60624 EPA Ass Environmental Site Assessment – URS 30 Jun 2015 Environmental Investigations (Stage IV), Hendon 60624 EPA Ass Vapour Risk Assessment – Hendon URS 31 Jul 2015 Investigation Area – Preliminary Vapour Risk Assessment 60624 EPA Ass Environmental Site Assessment – Hendon AECOM 29 Apr 2016 Broader Assessment Area (Stage 2), Hendon 61 Groundwater Prohibition Report – Hendon and environs EPA EPA file Report name Author Report date reference type 60624 EPA Ass Environmental Site Assessment – Hendon Greencap 16 Jun 2017 Broader Assessment Area (Stage 3), Hendon 61467 EPA Ass Environmental Site Assessment – April 2015 URS 24 Jun 2015 Vapour Monitoring Event at Laugh’n’Learn Child Care Centre, corner of Tapleys Hill Rd and West Lakes Boulevard 61467 EPA Ass Environmental Site Assessment – May 2015 URS 25 Jun 2015 Vapour Monitoring Event at Laugh’n’Learn Child Care Centre, corner of Tapleys Hill Rd and West Lakes Boulevard 61467 EPA Ass Environmental Site Assessment – August 2015 URS 16 Oct 2015 Vapour Monitoring Event at Laugh’n’Learn Child Care Centre, corner of Tapleys Hill Rd and West Lakes Boulevard 61467 EPA Ass Environmental Site Assessment – URS 22 Dec 2015 Laugh’n’Learn Child Care Centre, corner of Tapleys Hill Rd and West Lakes Boulevard, Hendon 61500 SCAR Site Contamination Audit Report – Fouad Abo Audit in 10,12,13,15,17,24 & 31 Circuit Drive, Hendon Progress 61606 VSCAP Voluntary Site Contamination Proposal – Norton Rose VSCAP in 10,12,13,15,17,24 & 31 Circuit Drive, Hendon Fulbright Australia Progress 62 Groundwater Prohibition Area – Hendon and surrounds Table A3–2 EPA information sources recorded in the EPA Public Register − former automotive components facility (components site) EPA EPA file Report name Author Report date reference type Former market garden 14756 SAR Site Audit Report – 187–193 Tapleys Hill Road, Adrian Hall 1 Aug 2008 Seaton Seaton service station 61259 S83A Environmental Site Assessment – BP Service AGC Woodward– 1 July 1992 Station environmental site assessment, Tapleys Clyde Hill Rd, Seaton 61259 S83A Groundwater Monitoring Event – Groundwater AGC Woodward– 4 Dec 1992 contamination assessment, BP Seaton Clyde 61259 S83A Environmental Site Assessment – AGC Woodward– 9 July 1993 Investigation of potential contaminant migration, Clyde BP Seaton Vehicle storage and maintenance site 61951 S83A Environmental Site Assessment – Preliminary Land and Water 13 Feb 2018 site investigation, 168 Tapleys Hill Rd, Royal Consulting Park 61987 SCAR Site Contamination Audit Report – 162–168 Steve Kirsanovs In progress Tapleys Hill Rd, Royal Park Commercial building (Indian restaurant & hairdresser) 60970 SCAR Site Contamination Audit Report – 150–152 Peter Ramsay 30 Sep 2013 Tapleys Hill Rd, Royal Park 61083 S83A Section 83A notification – 150–152 Tapleys TMK Engineering 5 Apr 2013 Hill Rd, Royal Park Former Royal Park service station 10573 S109 Environmental Site Assessment – Site BC Tonkin & 1 Sep 1991 contamination assessment investigations report, Associates 136–138 Tapleys Hill Rd, Royal Park 10573 S109 Groundwater Monitoring Event – Groundwater BC Tonkin & 1 Mar 1993 monitoring, 136–138 Tapleys Hill Rd, Royal Park Associates 10573 S109 Environmental Site Assessment – Further BC Tonkin & 1 July 1993 investigations report, 136–138 Tapleys Hill Rd, Associates Royal Park 10573 S109 Environmental Site Assessment – Royal Park BC Tonkin & 1 Aug 1995 Service Station Further Investigation Report, Associates 136–138 Tapleys Hill Rd, Royal Park 63 Groundwater Prohibition Report – Hendon and environs EPA EPA file Report name Author Report date reference type 10573 S109 Environmental Site Assessment – Initial site Rust PPK 20 Feb 1996 program, Royal Park, 136–138 Tapleys Hill Rd, Royal Park 10573 S109 Fate and Transport Modelling – Site Rust PPK 8 Aug 1996 Investigation and Solute Transport Modelling – Deeper Sand Layer – Esso Royal Pk, 136–138 Tapleys Hill Rd, Royal Park 10573 S109 Remediation Options Assessment – Site Rust PPK 8 Aug 1996 Remediation Investigation and Solute Transport Modelling – Esso Royal Pk, 136–138 Tapleys Hill Rd, Royal Park 10573 S109 Groundwater Monitoring Event – Esso Royal Rust PPK 3 Mar 1997 Park Report, 136–138 Tapleys Hill Rd, Royal Park 60268 SCAR Site Contamination audit notification – 136– Steve Kirsanovs In progress 138 Tapleys Hill Road, Royal Park 60279 S83A Vapour Monitoring Event – Soil Vapour OTEK 28 Sep 2012 Assessment, 136–138 Tapleys Hill Rd, Royal Pk 60279 S83A Environmental Site Assessment – Detailed Coffey 5 Jul 2011 risk assessment of former Esso Royal Park Service Station, 136–138 Tapleys Hill Road, Royal Park 60279 S83A Remediation – Multi-Phase Extraction Event, OTEK 29 Feb 2013 136 Tapleys Hill Road, Royal Park 60279 S83A Remediation – Multi-Phase Extraction Event, OTEK 3 Apr 2013 136 Tapleys Hill Road, Royal Park 60279 S83A Groundwater Monitoring Event – Groundwater OTEK 9 Apr 2013 monitoring event, 136–138 Tapleys Hill Rd, Royal Park 60279 S83A Groundwater Monitoring Event – Groundwater OTEK 30 Apr 2013 monitoring event, 136–138 Tapleys Hill Rd, Royal Park 60279 S83A Vapour Monitoring Event – Soil vapour Kleinfelder 1 Jul 2013 Monitoring Event Letter, 136–138 Tapleys Hill Rd, Royal Park 60279 S83A Detailed Site Investigation – Detailed Risk Kleinfelder 17 Jul 2015 Assessment, 136–138 Tapleys Hill Rd, Royal Park 64 Groundwater Prohibition Area – Hendon and surrounds EPA EPA file Report name Author Report date reference type Hendon Hotel 12539 S109 Environmental Site Assessment – Hendon SKM 16 Jul 2004 Hotel Environmental Investigation, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Environmental Site Assessment – Hendon SKM 13 Mar 2007 Hotel Remediation Project, additional environmental assessment, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Remediation – Hendon Hotel Remediation SKM 19 Jun 2007 Project, remediation action plan, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Remediation – Hendon Hotel Remediation SKM 11 Dec 2008 Project, UST removal and natural attenuation evaluation report, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Groundwater Monitoring Event – Additional SKM 12 Nov 2010 groundwater investigations, Hendon Hotel, 110– 120 Tapleys Hill Rd, Royal Park 12539 S109 Groundwater Monitoring Event – Additional SKM 21 May 2012 groundwater assessment, Hendon Hotel, 110– 120 Tapleys Hill Rd, Royal Park 12539 S109 Detailed Site Investigation – Detailed risk SKM 19 Oct 2012 assessment, Hendon Hotel, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Environmental Site Assessment – Additional SKM 3 May 2013 environmental investigations, Hendon Hotel, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Remediation – Remediation options Jacobs 12 May 2014 assessment, Hendon Hotel, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Site Management Plan – Hendon Hotel, 110– Jacobs 16 Jul 2014 120 Tapleys Hill Rd, Royal Park 12539 S109 Groundwater Monitoring and Management Jacobs 30 Mar 2015 Plan – Hendon Hotel, 110–120 Tapleys Hill Rd, Royal Park 12539 S109 Groundwater Monitoring Event – Hendon Jacobs 24 Jun 2015 Hotel, 110–120 Tapleys Hill Rd, Royal Park 65 Groundwater Prohibition Report – Hendon and environs EPA EPA file Report name Author Report date reference type Queensbury pump station 60939 S83A Environmental Site Assessment – Aurecon 3 Jul 2012 Queensbury Pumping Station, Hendon Former manufacturing and electroplating facility 60408 S109 Environmental Site Assessment – Site history Woodward Clyde 30 Oct 1996 report, TRW Carr site, Hendon 60408 S109 Environmental Site Assessment – Phase II Woodward Clyde 31 Mar 1997 soil investigation of TRW Carr site, Hendon 60468 S83A Environmental Site Assessment – FMG Engineering 3 Dec 2010 Environmental soil contamination assessment 61 Tapleys Hill Road, Hendon 61518 S83A Environmental Site Assessment – Phase 2B URS 30 Jul 2015 Environmental site assessment, Hendon Self Storage Former tin can manufacturing facility 61931 S83A Detailed Site Investigation – 24–30 Murray St, LWC 6 July 2018 Albert Park 61909 SCAR Site Contamination Audit – 24–30 Murray Graeme Miller In progress Street, Albert Park Tow truck operator site 12030 SAHC South Australian Health Commission Report SAHC 30 Sep 1991 – Albert Park project No. 43-12-01-01 Former Albert Park Tannery 10972 SAHC South Australian Health Commission Report SAHC 9 Sep 1988 – Albert Park Site 18004 S109 Environmental Site Assessment – SA Housing Australian 1 Mar 1989 Trust Hydrogeological Investigation of Albert Groundwater Park Site Consultants Former orchard and mixed manufacturing 17195 SAR Site Audit Report – 3 Dover Street, Royal Park Adrian Hall 1 Dec 2008 Former bushland and play area 12067 SAHC South Australian Health Commission Report SAHC 3 Jul 1992 – Lot 289 Royal Terrace, Lot 4 George Street & Lots 267, 268, 269, 270 & 271 Dover Street, Royal Park 66 Groundwater Prohibition Area – Hendon and surrounds EPA EPA file Report name Author Report date reference type Former vacant land 12229 SAHC South Australian Health Commission Report SAHC 16 Sep 1992 – Site history appraisal, Kingstone Avenue– Royal Terrace, Royal Park West Lakes residential development 12009 EPA Ass – – – Former West Lakes Council Depot 60333 S83A Groundwater Monitoring Event – Former West GHD 2 Sep 2010 Lakes Council Depot, 18 Frederick Road, West Lakes 60450 SCAR Site Contamination Audit Report – 18 Phillip Hitchcock 30 Oct 2015 Frederick Road, West Lake 11993 S109 Environmental Site Assessment – West Lakes Golder Associates 29 Sep 1999 Depot, 18 Frederick Rd, West Lakes 11993 S109 Contamination Management Plan – West Golder Associates 29 Sep 1999 Lakes Depot, 18 Frederick Road, West Lakes 11993 S109 Environmental Site Assessment – Human Golder Associates 16 May 2000 Health Risk Assessment and potential off-site groundwater contamination, Lochside Drive, West Lakes 11993 S109 Environmental Site Assessment – Addition Golder Associates 27 Jul 2001 environmental assessment information, West Lakes Depot, Lochside Drive, West Lakes 11993 S109 Environmental Site Assessment – GHD 1 Jan 2005 Environmental site assessment and site remediation strategy, former West Lakes Council Depot, West Lakes 11993 S109 Environmental Site Assessment – Report for GHD 1 Sep 2007 consolidated environmental assessment, former West Lakes Council Depot, 18 Frederick Rd, West Lakes Former Port Adelaide Waste Treatment Plant 12006 S109 Environmental Site Assessment – Preliminary PPK Environment & 27 Apr 1999 environmental site assessment, Port Adelaide Infrastructure Waste Water Treatment Plant, 16 Frederick Road, West Lakes 12006 S109 Environmental Site Assessment – Final report URS 12 Sep 2000 on environmental site assessment of the Port Adelaide Wastewater Treatment Plant, 16 Frederick Rd, West Lakes 67 Groundwater Prohibition Report – Hendon and environs EPA EPA file Report name Author Report date reference type 12006 S109 Environmental Site Assessment – Surface soil URS 20 Mar 2002 investigations at the Port Adelaide Wastewater Treatment Plant, West Lakes 12006 S109 Groundwater Monitoring Event – Additional URS 12 Aug 2002 groundwater investigations for the Port Adelaide Wastewater Treatment Plan, West Lakes 12006 S109 Groundwater Monitoring Event – Additional Parsons 26 Oct 2012 groundwater investigations, former Port Adelaide Brinckerhoff Wastewater Treatment Plan, 16 Frederick Rd, West Lakes 12006 S109 Groundwater Monitoring and Management Parsons 26 Nov 2012 Plan – Former Port Adelaide Wastewater Brinckerhoff Treatment Plan 12006 S109 Groundwater Monitoring Event – Groundwater Parsons 8 Jul 2014 monitoring – July 2013 to April 2014, former Port Brinckerhoff Adelaide WWTP, Frederick Rd, West Lakes Former coach depot 60983 S83A Notification of Site Contamination – Custom AEC Environmental 8 Oct 2012 Coaches, 7 Brandwood Street, Royal Park Seaton North Primary school oval 10074 SAR Site Audit Report – Environmental Audit, Alex Eadie 21 Mar 1996 Seaton North Primary School oval AMMI Stadium 61663 SCAR Site Contamination Audit Report – Adrian Webber 17 Mar 2017 Commercial and General Communities Pty Ltd, West – Portion of Area B – Portion of former AAMI Stadium Complex 61663 SCAR Site Contamination Audit Report – Adrian Webber 10 Dec 2017 Commercial and General Communities Pty Ltd, West – Balance of Area B – Portion of former AAMI Stadium Complex Unoccupied land 61674 S83A Notification of Site Contamination – 40 Port Golder Associates 25 Aug 2016 Road, Alberton 68 Groundwater Prohibition Area – Hendon and surrounds EPA EPA file Report name Author Report date reference type Former tin canning site 61787 S83A Environmental Site Assessment – Preliminary Land and Water 15 Nov 2016 site investigation, 983–985 Port Road Consulting Cheltenham 67187 S83A Environmental Site Assessment – Detailed Land and Water 27 Mar 2017 site investigation, 983 Port Road Cheltenham Consulting Former car sales and maintenance yard 61831 SCAR Site Contamination Audit Report – 969 Port James Fox 11 Sep 2018 Road, Cheltenham Former masonry monument business 11874 SAR Site Audit Report – Allotments 19, 20 & 23 Adrian Hall 15 Aug 2001 Third Avenue, Cheltenham 69 Groundwater Prohibition Report – Hendon and environs Appendix 4 Chlorinated hydrocarbons Chlorinated hydrocarbons are denser (heavier) than water. When released to the environment they can leach through the soil into groundwater and form a dense non-aqueous layer (DNAPL). Depending on the sediment type, microbial activity within the groundwater and aquifer hydraulic conditions, chlorinated hydrocarbons may persist for hundreds of years in aquifer sediments and groundwater123. Breakdown of the chlorinated hydrocarbons via reductive dehalogenation to ethene may occur under anaerobic conditions and PCE can be intrinsically biodegraded to form additional chemicals of concern such as TCE, DCE and VC. Biodegradation via microbial activity occurs when the groundwater conditions are suitable, resulting in the capacity to remove contaminant mass and reduce the plume concentrations124 PATHWAY FOR REDUCTIVE DEHALOGENATION FOR TETRACHLOROETHYLENE (PCE) T•trachlorMlhyi.M Trichloroethyi.nt, Oichloroelhyten• VlnVIChlo~ Ethene Ethane (PCE) (TCE) (DCE: ilorMJ'l (VC) Pot,t.lbl•l co, H fl ~ H fl H~rr H/- H~f=rH Ok::Moroelhlln. Chloro.thllne (OC:A) (CA) Figure 42 Microbial pathway for reductive dehalogenation for tetrachloroethylene (PCE)125 The International Agency for Research on Cancer (IARC) (1995)126 has classified TCE as Group 2A – probably carcinogenic to humans. A review by the United States Environment Protection Agency (US EPA) (2011)127, characterised TCE as carcinogenic in humans by all routes of exposure. The reduced chemical products from this dehalogenation process are also known to be harmful in varying degrees, the exception being ethene. Electroplating processes Electroplating is a process in which metal ions in solution are moved via an electric field to coat an electrode. Surface preparations prior to the electroplating requires the metal surfaces to be cleaned or degreased with solvents, hot alkaline detergent, acid or by electro-cleaning and ultrasonic cleaning. Once degreased, the metals prepared for plating are 123 Wisconsin Department of Natural Resources 2014, Understanding Chlorinated Hydrocarbons Behavior in Groundwater: Guidance on the Investigation, Assessment and Limitations of Monitored Natural Attenuation. 124 Suarez MP and Rifai HS 1999, ‘Biodegradation rates for fuel hydrocarbons and chlorinated hydrocarbons in groundwater’, Bioremediation 3:337–362. 125 WHO 2017, Guidelines for drinking water quality, fourth edition, World Health Organization, Geneva, http://www.who.int/water_sanitation_health/publications/2011/dwq_guidelines/en/. 126 IARC 1995, ‘Dry cleaning, some chlorinated solvents and other industrial compounds’, International Agency for Research on Cancer, IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Humans, Vol 63. 127 US EPA 2011, ‘Toxicological review of trichloroethylene’, Support of summary information on the integrated risk information system (IRIS), US Environmental Protection Agency, EPA/635/R-09/011F. 70 Groundwater Prohibition Area – Hendon and surrounds generally submerged in plating baths. These baths include chemicals such as metal cyanides, metal sulfates and/or other metals which are deposited on the prepared metal surfaces128. Figure 43 Electroplating bath (Fuse School, Global Education 2018) Petroleum hydrocarbons Due to the ability of petroleum hydrocarbons to be readily biodegraded by microbial activity in the groundwater, it is generally understood that there are appreciably higher rates of natural attenuation within petroleum hydrocarbon plumes. The longevity of petroleum-based groundwater plumes is much less than chlorinated hydrocarbon plumes, the extent of the plumes is relatively smaller and the reduction in plume size is more rapid 129. The Agency for Research on Cancer (ATSDR) (1999) has classified benzene as carcinogenic to humans and total petroleum hydrocarbons as probably carcinogenic to humans130. 128 Mandich NV and Snyder DL 2010, Modern Electroplating, 5th Edition, edited by Schlesinger M and Paunovic M, John Wiley & Sons, Hoboken, New Jersey, USA. 129 Wiedemeier TH, Rifai HS, Newell CJ and Wilson JT 1999, Natural Attenuation of Fuels and Chlorinated Solvents in the Subsurface, John Wiley & Sons, New York, USA. 130 ATSDR 1999, ‘Total petroleum hydrocarbons’, Agency for Toxic Substances and Disease Registry, Atlanta, GA: US Department of Health and Human Services, Public Health Service. 71 Groundwater Prohibition Report – Hendon and environs Appendix 5 South Australian geology and hydrogeology The geology of South Australia has had a very distinctive and interesting history over the last 2.7 billion years. Its geological provinces and basins have been shaped by depositional, igneous, orogenic and other alteration events. The main geological provinces are Curnamona Province, Gawler Craton, Musgrave Province and the Adelaide Fold Belt and Stuart Shelf, which includes the Kanmantoo Trough. Within these provinces are the various sedimentary basins, including Officer Basin, Murray Basin, Gambier Basin, Uley Basin and Eucla Basin (Cowley 2010). The South Australian groundwater is known to flow through Precambrian fractured rock and Palaeozoic, Mesozoic and Cainozoic era sediments. Pre-Cambrian and Cambrian The understanding of groundwater flow mechanisms in fractured rock aquifers of the Mount Lofty Ranges, Northern Adelaide Plains and Kangaroo Island is still developing. Groundwater contamination is difficult to characterise due to the difficulty in understanding groundwater flows and the natural mineralisation in these fractured rock aquifers. In the Adelaide metropolitan region it is known however that groundwater migration is across the Para and Eden−Burnside Faults from the Mount Lofty Ranges to the sedimentary aquifers of the Northern Adelaide Plains, Adelaide Plains and McLaren Vale areas. This groundwater migration provides a significant amount of recharge to the Quaternary and Tertiary aquifers in these receiving areas (Stewart et al 2009). Having said this, the groundwater recharging process in the Mount Lofty Ranges is still not well understood. Palaeozoic In central/northern South Australia, deep aquifer systems flow through the Permo-Carboniferous Boorthanna Formation (groundwater abstracted by Prominent Hill Mine) and the Cambrian Andamooka Limestone (groundwater abstracted by Olympic Dam Mine). The Boorthanna Formation is predominantly recharged from northern aquifer systems (Veitch et al 2006, Olympic Dam Draft EIS 2011). The Andamooka Limestone aquifer, however, is recharged predominantly through surface infiltration following significant rainfall events (Olympic Dam Draft EIS 2011). Pressures on these aquifers arise principally from mining abstraction. Mine waste infiltration from mining activities and township irrigation are potentially contaminating activities that may threaten the unconfined Andamooka Limestone. Mesozoic (Jurassic and Cretaceous) In central/northern South Australia, the most significant aquifers are the Mesozoic Cadna-owie Formation and Algebuckina Sandstone, which comprise in part the South Australian portion of the Great Artesian Basin. Recharge rates of these aquifers are very low, ranging from 0.1 mm/year to 5 mm/year, with residence times as long as 7,000 years (Veitch et al 2006). These Mesozoic artesian aquifers are not susceptible to surface site contamination due to the protection of the partly confining layer of the Bulldog Shale. Pressure on these aquifer systems arise from pastoral and mining abstraction (GABCC 2000). Cainozoic (Tertiary and Quaternary) The sediments of the Tertiary basins build deep groundwater aquifers (otherwise known as the T1–T4 aquifers). These deep aquifers are especially important for the supply of potable water to various market gardens, orchards, vineyards and stock watering in the Northern Adelaide Plains, Clare Valley, McLaren Vale, the York Peninsula and the Eyre Peninsula, and industries in the Adelaide metropolitan region. The Tertiary aquifers are mostly protected by the overlaying layers of widely impermeable confining sediments of the Hindmarsh Clay. Managed Tertiary aquifer storage and recovery schemes are being increasingly used to ‘waterproof ‘an area against low surface water availability during times of drought or low rainfall periods. Managed aquifer storage and recovery is the process of recharging surface water from created wetland areas into an aquifer for storages and then recovered months 72 Groundwater Prohibition Area – Hendon and surrounds later for potable use. Contamination of the Tertiary aquifers could arise from poorly managed aquifer storage and recovery schemes. Overlying the Tertiary sediments are the shallow, unconfined to semi-confined aquifers of the Adelaide Plains, Kangaroo Island, the York Peninsula and the Peninsulas, built up by Quaternary sands, gravels and clays, and calcareous sandstones, respectively. Due to the largely unconfined nature of the upper Quaternary aquifers, they can be particularly susceptible to chemical substances entering the groundwater from contaminating activities. Groundwater within the aquifers of the Quaternary sands is abstracted primarily for market gardens, vineyards and localised domestic use. 73