Attachment A - City of Sydney

Attachment A

Interim Audit Advice Letter – Review of

Remediation Action Plan for 33-37 Sophia

Street, Surry Hills

Z:\Projects\Jun Zuo & Li Ling Wu\318001143_33‐37 Sophia St Surry Hills\8. Deliverables\318001143_IAA_Sophia Street_15 March 2021.docx Ramboll Australia Pty Ltd

ACN 095 437 442

ABN 49 095 437 442

Ramboll Australia Pty Ltd Level 3, 100 Pacific Highway PO Box 560 North Sydney NSW 2060 T +61 2 9954 8100 www.ramboll.com Ref 318001143

15 March 2021

Jun Zou & Li Ling Wu c/o Perica & Associates Attn: Jason Perica

By email: [email protected]

Dear Jason,

RE: INTERIM AUDIT ADVICE LETTER NO. #1 - REVIEW OF REMEDIATION ACTION PLAN FOR 33-37 SOPHIA STREET, SURRY HILLS, NSW

1. INTRODUCTION

As a NSW Environment Protection Authority (EPA) accredited Contaminated Sites Auditor, I am conducting an Audit in relation to the subject site. This initial review has been undertaken to provide an independent review of the suitability and appropriateness of contaminated land investigations and a Remediation Action Plan (RAP).

It is proposed to develop the site as a 4-storey mixed use commercial and residential development with basement car park. The development is currently being considered by City of Sydney Council (Council) and Council have requested an audit of the remediation action plan (RAP) be submitted in support of the development consent.

This interim letter is based on a review of the documents listed below:

‘Report to Jun Zou & Li Ling Wu on Preliminary Site Investigation for Proposed Mixed Use Development at 33-37 Sophia Street, Surry Hills, NSW’ dated 15 February 2019, Environmental Investigation Services (EIS) (the PSI)

‘Preliminary (Desktop) Acid Sulfate Soil Assessment Proposed Mixed Use Development at 33-37 Sophia Street, Surry Hills, NSW’ dated 21 December 2020, JK Environments (JKE, formerly EIS) (the ASS Assessment)

‘Report to Jun Zou & Li Ling Wu on Detailed (Stage 2) Site Investigation for Proposed Mixed Use Development at 33-37 Sophia Street, Surry Hills, NSW’ dated 19 January 2021, JKE (the DSI)

‘Report to Jun Zou & Li Ling Wu on Remediation Action Plan (RAP) for Proposed Mixed Use Development at 33-37 Sophia Street, Surry Hills, NSW’ dated 11 February 2021, JKE (the RAP).

Ramboll - Jun Zou & Li Ling Wu Review of Remediation Action Plan for 33-37 Sophia Street, Surry Hills, NSW

Page 2

2. SITE DETAILS

2.1 Location

The site details are as follows:

Street address: 33-37 Sophia Street, Surry Hills, NSW (Attachment 1)

Identifier: Lot 1 in DP 998281 and Lots 1 and 2 in DP 606593

Local Government: City of Sydney Council

Owner: Jun Zou & Li Ling Wu

Site Area: Approximately 200 m2

Zoning: B4 Mixed Use

The boundaries of the site are well defined by adjoining properties to the east and west, by Sophia Street to the north and Kippax Street to the south.

2.2 Adjacent Uses

The site is located within an area of mixed residential, commercial and industrial land use. In the DSI, JKE note that surrounding land uses include a fashion warehouse and retailer to the north and east, offices and multi-storey apartment building to the south and an office block to the west.

The closest surface water body is Pyrmont Bay located over 1.5 km to the northwest.

2.3 Site Condition

The current site layout is shown in Attachment 2. During the PSI and DSI, JKE noted the following:

The site was completely paved with the majority of the site occupied by three terrace houses.

The southern section of the site was a concrete paved area which was used for parking.

The three two-storey buildings were constructed from brick, wood and metal with fibre cement clad balconies.

Paved areas in the northern and southern sections of the site appeared to be in good condition (no cracking present) and were constructed from concrete, brick and tile.

There were no exposed soils at the site.

No signs or indicators of former site use were identified at the time of the inspection.

The local topography slopes from southeast to northwest towards Pyrmont Bay. The site is located at the toe of the slope and has been levelled to accommodate the existing development.

2.4 Proposed Development

It is understood that development of the site is to involve demolition of the three existing terraces and construction of a mixed-use building with a loading dock/retail development on the ground floor and residential apartments above (Attachment 3). JKE indicate that, based on architectural drawings, the basement level will extend to the site boundaries and that, due to the slope of the site, the basement level will require excavation to a depth of approximately 3.6 metres below ground level (mbgl) at the western end of the site and approximately 4.5 mbgl at the eastern end of the site. It is understood that landscaped areas or gardens beds are not proposed as part of the development.

For the purposes of this audit, the ‘residential with minimal soil access’ land use scenario will be assumed as the most sensitive proposed land use.


Page 3

3. SITE HISTORY

EIS (now JKE) undertook a review of the site history in the PSI based on aerial photographs, site photographs, NSW EPA records, SafeWork NSW dangerous goods records, Council records and Certificates of Title. The review indicated that the site had been used for residential use since 1910 and did not identify any particular land uses which could have resulted in significant contamination. It is unclear from the report if the residences are the original terrace houses or if some demolition of previous structures has occurred.

Several potential off-site sources of contamination were identified, including:

Three motor garages located within 250 m and up-gradient of the site between 1950s and the 1990s.

Two dry cleaner businesses located within 250 m and up-gradient of the site between 1950s and the 1980s.

Four engineering manufacturing businesses located within 100 m and up-gradient of the site between the 1960s and the 1990s.

Based on the site history, JKE identified the following potential sources of contamination:

Fill material.

Hazardous building materials.

Off-site mechanic workshops, service stations, dry cleaners and engineering manufacturers.

3.1 Auditor’s Opinion

In the Auditor’s opinion, the site history provides an adequate indication of past activities. There were no indicators of significant industrial uses on-site that would have the potential to contaminate the site. Previous site uses with the most significant potential to cause contamination include importation of fill material and demolition of former buildings potentially containing hazardous building materials.

Migration of contaminants in groundwater from upgradient commercial and industrial sites may have occurred and has been considered in the conceptual site model.

4. CONTAMINANTS OF CONCERN

JKE provided a list of potentially contaminating activities and contaminants of concern in the DSI which is included as Figure 1 below.


Page 4

Figure 1: Potential Contaminant Sources and Contaminants of Concern from JKE DSI


The Auditor considers that the analyte list used by JKE adequately reflects the site history and condition.

There has been no assessment for the presence of per- and poly-fluoroalkyl substances (PFAS) but, in the Auditor’s opinion, there are no indications in the site history that they would be potential contaminants of concern on-site. PFAS are a contaminant of concern associated with electroplaters, identified as an off-site source, however, given the distance of these potential sources from the site (>100 m) and depth of groundwater (>4.5 mbgl, refer Section 5), the potential for PFAS to pose a risk to the current and future site use is considered to be low.


Page 5

5. STRATIGRAPHY AND HYDROGEOLOGY

Regional geological information presented by JKE in the DSI indicated that the site is underlain by Ashfield Shale of the Wianamatta Group, which typically consists of black to dark grey shale and laminite.

JKE completed three boreholes during the DSI (see Attachment 2). Borehole BH1 was completed using a drill rig to a depth of 6.0 mbgl and a groundwater monitoring well was installed screened within the sandstone from 2.9 to 5.9 mbgl. Boreholes BH2 and BH3 were competed using a hand auger to refusal on bedrock at depths of 1.0 and 1.3 mbgl respectively.

The stratigraphy encountered comprised relatively shallow fill to depths of 0.3 to 1.1 mbgl underlain by natural silty sandy clay or silty clayey sand and weathered sandstone bedrock from depths of between 0.9 and 1.3 mbgl. Groundwater was encountered in the sandstone in BH1 at a depth of approximately 5 mbgl.

A summary of the site stratigraphy and hydrogeology was provided by JKE in the RAP and is reproduced below.

Figure 2: Summary of Subsurface Conditions from JKE RAP

A desk top assessment for acid sulfate soils (ASS) was completed by JKE with reference to the National Acid Sulfate Soil Guidance (2018) documents and the Acid Sulfate Soil Management Advisory Committee (ASSMAC) Acid Sulfate Soil Manual (1998). Based on the information reviewed, JKE conclude that there is a low potential for ASS materials to be disturbed during the proposed development and that the elevation of the land above sea level, the geology and ASS risk mapping supports this conclusion. On this basis, JKE determined that an ASS management plan is not required.

JKE undertook a search for registered groundwater bores and identified 38 registered bores within approximately 1 km of the site. The nearest registered bore was located approximately 250 m from the


Page 6

site and was utilised for monitoring purposes. Two bores were registered for domestic and recreational uses and were located 946 m and 967 m and southeast of the site, on the opposite side of a ridge line. All of the remaining registered bores were for monitoring purposes.

JKE concluded in the DSI that based on the site stratigraphy, the potential for viable groundwater abstraction at the site for beneficial use was low and that use of groundwater is not proposed as part of the development.


The Auditor considers that the depth of fill and underlying stratigraphy have been adequately characterised for the purposes of remediation planning. The heterogeneity and extent of fill material has the greatest potential to impact the remediation of the site. Further investigation to characterise fill material is not considered necessary prior to demolition and remediation given the access restrictions due to site infrastructure and limitations of borehole investigations. Further characterisation of fill is proposed in the RAP following demolition, as discussed in Section 7 below.

Groundwater was encountered at a depth of approximately 5 mbgl in the sandstone bedrock. The Auditor agrees that based on the site location, stratigraphy and proposed site use, abstraction and use of groundwater is unlikely.

6. SUMMARY OF SITE CONTAMINATION

During the DSI, JKE completed three boreholes and collected soil samples and one groundwater sample for laboratory analysis for contaminants of concern. A judgemental sampling plan was adopted to achieve site coverage and due to site accessibility constraints.

JKE completed field screening of soil samples for volatile organic compounds (VOCs) using a photoionisation detector (PID). No elevated readings were recorded. Gauging of groundwater well BH1/MW1 with an interface probe did not detect any light non aqueous phase liquid (LNAPL) or dense non aqueous phase liquid (DNAPL).

Soil analytical results were compared to Tier 1 screening criteria from the National Environmental Protection (Assessment of Site Contamination) Measure 1999 (as amended 2013) (NEPM 2013). SOIl samples were also assessed against the Waste Classification Guidelines, Part 1: Classifying Waste (2014) to determine waste classification. Groundwater analytical results were compared to Australian Drinking Water Guidelines 2011 (updated 2018) for BTEX compounds and selected VOCs and the World Health Organisation (WHO) Guidelines for Drinking Water Quality (2008) for petroleum hydrocarbons.

The Auditor has reviewed the selected site assessment criteria (SAC) and considers them appropriate. It is noted that JKE adopted health screening criteria for the ‘residential with minimal opportunities for soil access, including dwellings with fully/permanently paved yards like high-rise buildings’ exposure scenario (HIL-B). As the development will include a basement and ground level retail, this exposure scenario is considered conservative and the health screening criteria for ‘commercial/industrial’ exposure scenario (HIL-D) could be considered adequately protective for the proposed future land use. Adoption of HSL-D for assessment of potential vapour intrusion is recommended in NEPM 2013 as appropriate for basements and ground level retail.

A total of six primary soil samples and two field quality control samples were submitted for analysis for heavy metals, PAH, TRH and BTEX and three primary samples for PCB, OCP, OPP and asbestos (presence/absence).

One primary groundwater sample and one field duplicate sample were analysed for heavy metals, PAH, TRH and VOCs, including BTEX and chlorinated VOCs.


Page 7

A summary of the soil and groundwater investigation results from the DSI that were used to inform the RAP is provided below:

Concentrations of TRH (F2), TRH (F3), benzene, naphthalene, total PAH and carcinogenic PAHs were detected above the SAC in samples of fill material.

Fibrous asbestos (Chrysotile asbestos in the form of matted material) was detected in one fill sample.

JKE provided a preliminary waste classification for the fill based on the DSI results which classified the fill as Restricted Solid Waste (non-putrescible) containing Special Waste (asbestos). This classification was based on TRH concentrations which were considered to be associated with the slag rather than with petroleum. Further sampling and TRH analysis occur using a silica gel clean-up was recommended to confirm this.

JKE considered that the natural soil and bedrock at the site is likely to meet the definition of VENM for off-site disposal or re-use purposes but indicated that further assessment via sampling and/or inspection is required following the removal of the overlying fill to confirm this classification prior to off-site disposal of the waste.

JKE recommended that, following demolition, a waste classification be undertaken on the fill and a confirmatory waste classification report be prepared. The waste classification is to include sampling from test pits in previously inaccessible areas of the site and analysis of fill samples for heavy metals, TRHs, BTEX and PAHs, including leachable concentrations (TCLP).

Concentrations of contaminants of concern in groundwater were below SAC, with the exception of zinc which exceeded the adopted ecological criteria. JKE consider the elevated result is likely to be indicative of regional groundwater background concentrations rather than on on-site contamination source and consider that there is a low risk to ecological receptors.


The DSI prepared by JKE was reviewed by the Auditor and is considered to have sufficiently characterised fill, soil and groundwater at the site for the purposes of remediation planning. The site assessment activities undertaken are considered to have met the requirements of the NSW EPA (2020) Contaminated Land Guidelines: Consultants Reporting on Contaminated Land and NSW EPA (2017) Contaminated Land Management: Guidelines for the NSW Site Auditor Scheme (3rd Edition).

Fill comprises silty clayey sand and gravel with ash, slag and other anthropogenic inclusions such as broken brick and demolition rubble. Analytical results have indicated that the fill contains concentrations of TRH, benzene, naphthalene, total PAH, carcinogenic PAHs and asbestos above the SAC which requires management or remediation. As the development involves the excavation of a basement across the extent of the property footprint, removal of the fill material will be undertaken through the development process which will remove the source of the contamination. The Auditor agrees that additional characterisation of the fill material should be undertaken in previously inaccessible areas of the site following building demolition to confirm the waste classification prior to off-site disposal.

Elevated levels of zinc were detected in the groundwater sample from BH1/MW1 which exceeded the adopted freshwater criteria. The Auditor agrees with JKE’s conclusions that the concentration is likely to represent background groundwater conditions and does not require any further assessment or management.


Page 8

7. CONCEPTUAL SITE MODEL

A conceptual site model (CSM) is a representation of the contaminant source, pathway and receptor linkages at a site. JKE developed a CSM and updated it based on the results of the DSI to inform the RAP. The CSM developed by JKE and included in the RAP is summarised below:

Source:

- Fill impacted with PAH, TRH, BTEX and asbestos or potential other unexpected contamination.

- Hazardous building materials from construction and demolition of historical buildings resulting in surface impacts or incorporated into shallow fill.

Affected media:

- Soils, although it is noted that asbestos fibres can affect air, and soil vapour.

- Groundwater was not considered to be contaminated.

Exposure Pathways:

- Direct contact, ingestion or inhalation of contaminated soil and dust or vapours.

Receptors:

- Future site occupants (commercial and residential site users).

- Construction workers and intrusive maintenance workers.

- Off-site human receptors including adjacent residential and commercial site users.

Potentially Complete Source-Pathway-Receptor Linkages:

- Vapour intrusion into the proposed basement and/or building (from soil contamination); and

- Contact (dermal, ingestion or inhalation) with exposed soils during the construction and excavation works during the proposed development.

The above exposure mechanisms were identified during development, however JKE note that these exposure mechanisms will be eliminated post-development since all contaminated fill will be removed from site to allow construction of the basement.

JKE identified data gaps in the CSM. The primary data gap identified was the restricted spatial distribution of the sampling locations due to the existing buildings at the site. The DSI recommended additional soil sampling and inspection post-demolition in relation to waste classification of fill material to address this data gap and these requirements are addressed in the RAP.


The CSM developed is considered an adequate basis for assessing remedial requirements. The data gaps identified by JKE are addressed through the remediation and validation proposed in the RAP and discussed in Section 8.

8. EVALUATION OF PROPOSED REMEDIATION

8.1 Remediation Required

Based on the investigations previously completed by JKE, the contaminants of concern that require remediation are considered to be confined to the fill material present across the full extent of the property footprint to depths of between approximately 0.3 and 1.1 mbgl. JKE identify that the depth of fill in areas of the site that were not accessible during the DSI is a data gap and propose excavation of


Page 9

test pits following building demolition to provide additional information regarding the required vertical extent of remediation and for waste classification as outlined below. The final vertical extent of the remediation will be established via the validation process.

The remediation works are proposed to be undertaken following removal and disposal of hazardous materials, demolition of the buildings, lawful removal of demolition waste material off-site and exposure of underlying soil.

8.2 Evaluation of RAP

The Auditor has assessed the RAP by comparison with the checklist included in NSW EPA (2020) Contaminated Land Guidelines: Consultants Reporting on Contaminated Land. The RAP was found to address the required information, as detailed in Table 8.1, below.

Table 8.1: Evaluation of Remedial Action Plan

Remedial Action Plan Auditor Comments

Remedial Goal

The goal of the remediation is to reduce human health and environmental risks associated with actual and potential site contamination to an acceptable level, in order to render the site suitable for the proposed development from a contamination viewpoint.

The RAP objectives are to:

Provide a methodology to undertake inspections and further sampling for waste classification assessment after demolition;

Provide a methodology to remediate and validate the site;

Outline site management procedures to be implemented during remediation work; and

Provide an unexpected finds protocol to be implemented during the development works.

In the Auditor’s opinion, the goal and objectives of the RAP are appropriate.

Discussion of the Extent of Remediation Required

The extent of remediation is removal of fill material across the full extent of the property footprint as discussed in Section 8.1 above.

Prior to removal, additional sampling of the fill material in previously inaccessible areas is proposed through test pitting to confirm the vertical extent of fill material and waste classification.

The extent of remediation is appropriate.

Remedial Options

Remedial options were assessed and included on-site treatment, off-site treatment, containment and capping and off-site disposal.

The Auditor considers that an appropriate range of options were considered.

Selected Preferred Option and Rationale

The preferred option was discussed within the RAP as the most practical, technically feasible and economically viable option as the fill material requires removal to construct a basement.

The Auditor considers the preferred option and rationale to be appropriate.

Description of Remediation to be Undertaken

The RAP outlines the following sequence of work:

1. Site establishment;

2. Demolition and removal of structures and pavement;

The RAP includes sufficient detail on the remediation staging and methodology to be practically implemented.


Page 10


3. Completion of the waste classification assessment; and

4. Remediation and validation at the site.

As the fill is to be excavated to the full extent of the site boundaries, shoring may be required. In the event that piling occurs prior to remediation, a procedure is outlined to minimise cross contamination of natural materials with fill.

A Hazardous Building Materials Survey is to be completed prior to building demolition. A clearance certificate is to be obtained by the demolition contractor following the removal of any hazardous materials.

Waste Classification Assessment: Soil/fill samples are to be collected from four test pits distributed on a judgemental plan across the site following demolition of the buildings and removal of the pavements. If any unexpected finds are encountered (e.g. stained or odorous soil, discoloured soils, underground infrastructure such as tanks etc), these areas must be targeted with additional sample locations. Sampling is to occur using an excavator. Samples are to be collected from each fill profile and from the top (~ 0.5 m) of the natural soil/bedrock beneath the fill.

Excavation and Disposal of Fill: The remediation area is to be excavated to the base of the fill and surface of the underlying natural soil (or bedrock, whichever is encountered first). Excavation is to occur methodically, starting at the end of the site furthest from the load-out point and working back towards the load-out point to minimise the potential for cross contamination.

The contaminated fill should be excavated/removed prior to the commencement of bulk excavation of the natural soil/bedrock to limit the potential for cross-contamination and blending of waste streams.

Proposed Validation Criteria

For waste classification purposes, the soil data will be assessed against the NSW EPA (2014) Waste Classification Guidelines, Part 1: Classifying Waste and any associated approvals such as the General Approvals of Immobilisation 2009/07 and 1999/05 where relevant.

The soil data for the site should also be assessed against the human-health based SAC (HSL/HIL-B) for ‘residential with minimal opportunities for soil access’ exposure setting based on Schedule B1 of NEPM 2013 (consistent with the DSI).

VENM and other imported materials to be consistent with expectations for those materials.

Recycled materials are to meet the criteria of the relevant exemption/order under which they are produced.

Acceptable.

Proposed Validation Testing

Excavation: one sample per 25 m2 of the base of the excavation (i.e. on a 5 m by 5 m grid), with additional samples targeting any additional areas identified during the inspection where fill removal does not appear adequate. Excavation walls are not expected to be

The proposed validation testing of the excavation is acceptable.

The Auditor notes that imported material must either be VENM, ENM or be classified under a Resource Recovery Exemption. The density of testing would need to be commensurate with the


Page 11


exposed as it is anticipated that piling will occur first to facilitate the fill removal. If the walls are exposed, sampling must occur every 5 m (lineal), targeting the fill profiles and the underlying natural soil at each location. Analysis for PAH, TRH, BTEX and asbestos (500 ml).

Re-use of Excavated Material: no reuse of material is proposed as the soil is to be excavated to construct a basement. Following removal of fill and validation of natural soils, waste classification documentation is to be prepared for the remaining natural soil/bedrock to be excavated. The frequency of this sampling is not specified.

Imported Material:

VENM - Minimum of three samples per source up to 100 m3, then one sample per 100 m3 thereafter. Analysis for metals, TRH/BTEX, PAHs, pesticides, PCBs and asbestos.

Recycled materials - One sample per 100 m3 (minimum of three samples per source/material type). Analysis for metals, TRH/BTEX, PAHs, pesticides, PCBs and asbestos 10 L field screening and 500 ml as per NEPM 2013.

Quarried materials - At the validation consultant’s discretion based on supplier documentation. Where sampling occurs, this is to be consistent with that specified above for imported “VENM”.

VENM documentation to be provided (should include source site history to demonstrate analytes are appropriate). Additional analysis is required for any other CoPC identified in the source site history.

Material to be inspected upon importation to confirm it is free of visible/olfactory indicators of contamination and is consistent with documentation.

documentation provided and the consistency of the results.

Material to be inspected upon importation to confirm it is free of visible/olfactory indicators of contamination and is consistent with documentation.

Contingency Plan if Selected Remedial Strategy Fails

The remedial strategy has a low risk of failure, as validation failure would lead to further excavation.

Contingency procedures are provided for unexpected finds and failure to validate imported materials.

In the Auditor’s opinion, the remediation strategy has a low risk of failure as validation failure would require additional excavation and validation.

The procedure for handling unexpected finds, which includes stopping work and identification of materials, is appropriate and practical and can be implemented within the proposed remediation strategy.

Interim Site Management Plan (before remediation)

Residential land use of the site will cease and no interim site management measures are considered necessary.

All demolition works are to occur in accordance with the relevant codes, guidelines and standards, and with reference to the findings of the hazardous building materials assessment report.

The site is currently covered by hardstand and buildings, preventing access to soils. The Auditor agrees that no interim management is required.

Site Management Plan (operation phase) including stormwater, soil, noise, dust, odour and OH&S

Requirements included in Section 10 of the RAP, including the requirement for an asbestos management plan (AMP) and asbestos removal control plan (ARCP).

Acceptable.

The potential for cross contamination of materials during piling and shoring works is discussed.

Remediation Schedule and Hours of Operation Acceptable.


Page 12


The project duration was not provided in the RAP.

The RAP identifies that hours of operation should be between those approved by council/the consent authority under the development approval process

Contingency Plans to Respond to Site Incidents

The validation consultant should be contacted if any unexpected conditions are encountered at the site. This should enable the scope of remedial/validation works to be adjusted as required. If any incident occurs on site, the validation consultant should be advised to assess potential impacts on site contamination conditions and the remediation/validation timetable.

The Auditor notes that the RAP provides management and contingency plans that are applicable for the proposed works.

Licence and Approvals

The RAP outlines regulatory requirements under SEPP 55, Protection of the Environment Operations (POEO) Act 1997 and the POEO (Waste) Regulation 2014.

The remediation works are assessed as Category 2 woks under SEPP 55.

The RAP specifies that appropriate SafeWork NSW notification will be required for asbestos removal works or handling. Contractors are also required to be appropriately licensed for the asbestos-related remediation works undertaken (i.e. Class A licence based on the asbestos at this site being friable).

An appropriately licensed landfill must be selected and the material tracked from the site to the landfill in accordance with relevant regulations.

Acceptable.

Contacts/Community Relations

Project contacts are provided in the RAP and are to be displayed on signs located adjacent to the site access and within the work area. Direct community consultation will be undertaken.

Acceptable.

Long Term Environmental Management Plan

The remediation will result in the removal of contaminated material and no long-term management will be required.

The Auditor agrees that, following remediation in accordance with the RAP and successful validation, all contamination will be removed from the site and long-term management will not be required.

Waste Management

The RAP details waste classification, tracking and disposal procedures including documentation requirements. It also requires the remediation contractor to develop a waste management or recycling plan to minimise the amount of waste produced by the site. This should, as a minimum, include measures to recycle and re-use natural excavated material wherever possible.

The waste management procedures detailed in the RAP are appropriate and practical.

The Auditor notes that successful validation of natural materials will be required to allow reuse of material from the site.

JKE conclude in the RAP that “The remediation is considered to be straight forward and includes the excavation and off-site disposal of all fill, which will occur to facilitate construction of the basement. Removal of the fill will remove the identified contamination and in turn will eliminate the risks posed by the contaminants. Hence, JKE are of the opinion that the site can be made suitable for the proposed development provided the proposed development occurs as planned and this RAP is implemented accordingly. A site validation report should be prepared on completion of remediation activities and should be submitted to the consent authority”.


Page 13


In the Auditors’ opinion, the proposed remediation works are appropriate. If adequately implemented, the RAP should be able to ensure that the site is suitable for the proposed land uses through the removal of fill impacted by chemical contaminants and asbestos containing material. Successful validation will be required to confirm this.

9. CONCLUSIONS AND RECOMMENDATIONS

The site investigations (PSI and DSI) have been reviewed by the Auditor and are considered to have been completed in general accordance with the requirements of the NSW EPA (2020) Contaminated Land Guidelines: Consultants Reporting on Contaminated Land and NSW EPA (2017) Contaminated Land Management: Guidelines for the NSW Site Auditor Scheme (3rd Edition).

The site history and potential for contamination is considered to have been sufficiently well assessed to allow for adequate sampling of soil and groundwater to characterise contamination at the site and inform remediation planning. The results of the DSI indicated that fill was present at the site containing inclusions of ash, slag and other anthropogenic materials. Analytical results have indicated that the fill contains concentrations of TRH, benzene, naphthalene, total PAH, carcinogenic PAHs and asbestos above the SAC which require management or remediation.

Elevated levels of zinc were detected in the groundwater sample from BH1/MW1 which exceeded the adopted freshwater criteria. The Auditor agrees with JKE’s conclusions that the concentration is likely to represent background groundwater conditions and does not require any further assessment or management.

A RAP has been prepared to address the soil contamination and as the proposed development involves the excavation of a basement across the extent of the property footprint, remediation through removal of all fill and off-site disposal to a licensed landfill is the preferred remediation option. The Auditor has reviewed the RAP and considers this strategy to be a practical, technically feasible and environmentally justifiable approach given the nature and extent of the identified contamination.

The RAP provides sufficient detail to ensure the remediation and validation of the site is completed in a manner consistent with relevant laws, policies and guidelines and to ensure that site can be made suitable for the proposed mixed commercial and residential development.

The RAP includes the requirement for additional characterisation and waste classification of fill materials following demolition of site buildings and the Auditor agrees that additional characterisation should be undertaken in previously inaccessible areas of the site to confirm the waste classification prior to off-site disposal.

In the Auditors’ opinion, the proposed remediation works are appropriate. If adequately implemented, the RAP should be able to ensure that the site is suitable for the proposed land uses through the removal of fill impacted by chemical contaminants and asbestos containing material. Successful validation will be required to confirm this. The remediation and validation works should be overseen by a suitably qualified environmental consultant and documented in a Validation Report. The Validation Report should be reviewed by the Auditor and a site audit statement and supporting site audit report prepared to confirm the site has been remediated in accordance with the approved RAP and is suitable for the proposed future use.


Page 14

10. LIMITATIONS

This interim audit advice was conducted on the behalf of Jun Zou and Li Ling Wu for the purpose of assessing the suitability and appropriateness of a remedial action plan (RAP). This summary report may not be suitable for other uses.

The Auditor has relied on the documents referenced in Section 1 in preparing the Auditor’s opinion. The consultants included limitations in their reports. This interim audit advice must also be subject to those limitations. The Auditor has prepared this document in good faith, but is unable to provide certification outside of areas over which the Auditor had some control or is reasonably able to check. If the Auditor is unable to rely on any of those documents, the conclusions of this interim audit advice could change.

It is not possible to present all data which could be of interest to all readers of this interim audit advice. Readers are referred to the referenced reports for further data. Users of this document should satisfy themselves concerning its application to, and where necessary seek expert advice in respect to, their situation.

* * *

Consistent with the NSW EPA requirement for staged ‘signoff’ of sites that are the subject of progressive assessment, remediation and validation, I advise that:

This advice letter does not constitute a Site Audit Report or Site Audit Statement.

At the completion of the remediation and validation I will provide a Site Audit Statement and supporting documentation.

This interim advice will be documented in the Site Audit Report.

Yours faithfully Ramboll Australia Pty Ltd

Louise Walkden EPA Accredited Site Auditor 1903

Attachments: 1 Site Locality Plan

2 Borehole and Groundwater Well Location Plan

3 Proposed Development Design

K

I

P

P

A

X

S

T

R

E

E

T

S

O

P

H

I

A

S

T

R

E

E

T

F

O

V

E

A

U

X

S

T

R

E

E

T

W

A

T

E

R

L

O

O

S

T

R

E

E

T

L

A

C

E

Y

S

T

R

E

E

T

L

IT

T

L

E

C

O

L

L

IN

S

S

T

R

E

E

T

C

O

R

B

E

N

S

T

R

E

E

T

PL

OT

D

AT

E: 1

9/0

1/2

02

1 1

0:1

0:1

6 A

M D

WG

F

IL

E: Z

:\5

E

IS

\5

C E

IS

JO

BS

\3

20

00

'S

\E

32

15

3P

L S

UR

RY

H

IL

LS

\C

AD

\E

32

15

3P

L.D

WG

SITE

E32153PL

Report No:

Location:

Title:

33-37 SOPHIA STREET

SURRY HILLS, NSW

© JK ENVIRONMENTS

This plan should be read in conjunction with the Environmental report.

Figure No:

SITE LOCATION PLAN

1

SOURCE: http://www.whereis.com/

AERIAL IMAGE SOURCE: MAPS.AU.NEARMAP.COM, 27 DEC 2018.

SITE

Attachment 1: Site Locality

K

I

P

P

A

X

S

T

R

E

E

T

S

O

P

H

I

A

S

T

R

E

E

T

BH2 (1.0)

BH3 (1.1)

BH/MW1 (0.3)

PLO

T D

AT

E: 19/01/2021 10:10:28 A

M D

WG

F

ILE

: Z

:\5 E

IS

\5C

E

IS

JO

BS

\32000'S

\E

32153P

L S

UR

RY

H

ILLS

\C

AD

\E

32153P

L.D

WG

0

SCALE@A3

2 4 6 8 10

1:200

METRES

Report No:

E32153PL

Location:

Title:

33-37 SOPHIA STREET

SURRY HILLS, NSW

© JK ENVIRONMENTS

Figure No:

This plan should be read in conjunction with the Environmental report.

SAMPLE LOCATION PLAN

2

AERIAL IMAGE SOURCE: MAPS.AU.NEARMAP.COM, 27 DEC 2018.

LEGEND

APPROXIMATE SITE BOUNDARY

BOREHOLE LOCATION, NUMBER AND DEPTH OF FILL (m)BH(Fill Depth)

BOREHOLE AND GROUNDWATER MONITORING WELL LOCATION, NUMBER AND DEPTH OF FILL (m)BH/MW(Fill Depth)

Attachment 2: Borehole and Groundwater Well Location Plan

LEVEL 4

RL 46.70

ROOF

RL 49.80

LEVEL 1 (G)

RL 35.70

LEVEL 2

RL 40.50

LEVEL 3

RL 43.60

4935 250 4755

A

DA 205

15M HOB MAX AT BOUNDARY

SB SB

360

02

400

240

03

100

310

03

100

GL1

AF1

FB

GL1

AF1

LOBBY

RL 36.53

AC

AC

CON2

GL2 GL2

GL1GL1

GL1

GL1

GL3 GL3

FB

130-132KIPPAX ST

COMMERCIAL

39-41SOPHIA ST

RESIDENTIAL

SITE 116-120KIPPAX ST

COMMERCIAL

LINE OF BASEMENT

BASEMENT 1

RL 32.10

CON2

BL1

830

397

0

MEZZANINE

RL 38.10

CON1

RL 50.95

RL 50.10

GL3

GL2

GL1 AF1

GL2 GL2 GL2

GL1

GL1

GL1GL3 GL3 GL3

CON1

AF1

9940

CON1

1

DA 401

1

DA 403

1

DA 402

1

DA 404

OUTLINE OF PROPOSED BOARDING HOUSE

D/2020/22539-41 SOPHIA STSHOWN DOTTED

51.87

53.12

SC

VFSG

SD SD

GLASS + METAL VERTICAL FOLDING DOOR WITH PANELISATION AS SHOWN + TAPERING SOLID PANEL TO ADJUST TO SLOPE

ACAF1AF2

BLBL1CON1CON2CON3CON4FBGL1GL2GL3LBSC

ALUMINIUM CHANNEL, POWDERCOAT FINISH, DULUX ELECTRO, BASALT, FLATALUMINIUM FRAMED WINDOW + DOOR, POWDERCOAT FINISH, DULUX ELECTRO, BASALT, FLATALUMINIUM FRAMED WINDOW, 3 x PANE SASHLESS DOUBLE HUNG WINDOW, POWDERCOAT FINISH, DULUX ELECTRO, BASALT, FLATSTEEL FLUTED PANEL, COLORBOND, BASALT, MATTSTEEL PALISADE BALUSTRADE, DULUX FERREKO NO 3, NATURAL GREYCONCRETE INSITU, GROOVED, CEMENTITIOUS COATING, NATURAL GREYCONCRETE INSITU, CEMENTITIOUS COATING, NATURAL GREYCONCRETE INSITU, CEMENTITIOUS COATING, COLOUR TO MATCH FBCONCRETE INSITU, NATURALGLAZED BRICK TILE, AUSTRAL, BURLESQUE, INDULGENT WHITEGLASS CLEAR, VIRIDIAN, VFLOATGLASS TRANSLUCENT, VIRIDIAN, LUMINA MIST CLOUDGLASS TRANSLUCENT, VIRIDIAN, LUMINA MIST GREYLETTERBOXESALUMINIUM PALISADE SCREEN, DULUX ELECTRO, BASALT, FLAT

SDSGST1VF

METAL DOOR PANEL + FACING, COLORBOND, WHITEHAVENBUILDING IDENTIFICATION SIGNAGESTEEL FRAMED WINDOWS, DULUX FERREKO NO 3, NATURAL GREYVERTICAL FOLDING DOOR, DULUX ELECTRO, BASALT, FLAT

MODIFICATIONS:

1. DEVELOPMENT DATA UPDATED TO REFLECT AMENDMENTS.2. BASEMENT 1 UPDATED TO ACCOMMODATE STAIR + TURNTABLE RELOCATION, ACCESS

RECONFIGRED TO PERMIT ACCESS FOR RETAIL + RESIDENTIAL TO HYDRAULIC LIFT.3. HYDRAULIC LIFT ACCESS TO SOPHIA STREET, REDUCED WIDTH OF DRIVEWAY RAMP,

STAIR ADDED TO STREET INTERFACE, AWNING DELETED TO SOPHIA ST, ROLLERSHUTTER REPLACED WITH GLAZED VERTICAL FOLDING DOOR, METAL DOOR + FACINGSHOWN TO SERVICE DOORS FACING SOPHIA STREET.

4. TURNTABLE + STAIR RELOCATED, MEZZANINE EXTENDED, RETAIL AREA AT GROUNDREDUCED.

5. AWNING DELETED TO KIPPAX ST.6. SNORKEL DELETED + UNIT REPLANNED, GARBAGE CHUTE RELOCATED.7. BALCONY DEPTH INCREASED.8. CLOTHES DRYING AREA SHOWN BEHIND OBSCURE GLASS SCREEN.9. FUSEABLE LINK NOTE ADDED TO WINDOW ALONG BOUNDARY.10. PV CELLS ADDED, HW PLANT + AC CONDENSERS ADDED TO SCREENED AREA ON

ROOF 1.45M HIGH, GREEN ROOF REDUCED, ACCESS HATCH ADDED, BALLAST SHOWN.

00

Level 10 257 Clarence Street, Sydney NSW 2000T (61 2) 9358 2588 www.stanisic.com.au ABN 11002633481

do not scale from drawings.

issue amendment date

scale drawn

checked

drawing no

drawing

project

issue

project no

legend

client

scale barthe layout shown and the areas noted on this drawing are indicative only. layouts are tobe read in conjunction with floor plans, elevations + sections.

NSW ARB Frank Stanisic 4480

J.ZUO + L. WU C/O GENCORP PTY LTD

1 2 3 4 5

m

1:100@A11:200@A3

1 2 3 4 5

m

1:100@A11:200@A3

northarchitect

B

17-D

ec-

20 1

1:37

:02

AM

17 022

MIXED USE DEVELOPMENT

JN

FS

DA 202

NORTH ELEVATION (SOPHIASTREET)

33-37 SOPHIA STREET SURRY HILLSA ISSUE FOR DEVELOPMENT APPLICATION 03.02.20B ADDITIONAL INFORMATION RESPONSE (LETTER 03/11/20) 17.12.20

10

Attachment 3: Proposed Development Design

Attachment A - City of Sydney

Documents

Transcript of Attachment A - City of Sydney