Controlled Copy ___ Site Audit Suitability of Remediation Action Plan, Part of Block 1 Southlands, 28 McPherson Street, Banksmeadow for Orica Australia Pty Ltd August 2015 J1130.23R-rev0 CMJA C. M. Jewell & Associates Pty Ltd Site Audit Suitability of Remediation Action Plan, Part of Block 1 Southlands, 28 McPherson Street, Banksmeadow August 2015 J1130.23R-rev0 Controlled Copy 1 Mr Stephen Corish Orica Australia Pty Ltd 16-20 Beauchamp Road MATRAVILLE NSW 2036 2 The Secretary Attention: Mr Chris Wilson NSW Department of Planning and Environment GPO Box 39 SYDNEY NSW 2001 3 The General Manager Botany Bay City Council PO Box 331 MASCOT NSW 1460 4 CMJA Library C. M. Jewell & Associates Pty Ltd ABN: 54 056 283 295 1/13 Kalinda Road, Bullaburra, NSW 2784 PO Box 10, Wentworth Falls, NSW 2782 Phone (02) 4759 3251 Fax (02) 4759 3257 www.cm-jewell.com.au [email protected] ___________________________________ CHRIS JEWELL Auditor This report has been prepared specifically for Orica Australia Pty Ltd. This report, the original data contained in the report, and its findings and conclusions remain the intellectual property of C. M. Jewell & Associates Pty Ltd. This report should not be used by other persons or for other purposes than those for which it was commissioned, and should not be reproduced except in full and with the permission of C. M. Jewell & Associates Pty Ltd. C. M. Jewell & Associates Pty Ltd will not support and will bear no liability for unauthorised use of this report. Site Audit – Suitability of RAP, Part of Block 1 Southlands, 28 McPherson Street, Banksmeadow Lot 1 DP85542 Lot 11 DP109505 Source: JBS&G 2015 Report Ref: J1130.23R The Site (proposed Lot 10) Rev: 0 Site Audit Statement SA263/3 Rev Date: 2-Aug-15 Current Lots / DPs C. M. Jewell & Associates Pty Ltd Author: naa Figure 1 Site Audit Report Site Audit – Suitability of RAP, Part of Block 1 Southlands, 28 McPherson Street, Banksmeadow i TABLE OF CONTENTS 1.0 INTRODUCTION .............................................................................................................1 1.1 Background .......................................................................................................................... 1 1.2 EPA Notices Relevant to the Site ........................................................................................ 3 1.3 Scope and Structure of Review Report ................................................................................ 4 1.4 Limitations and Intellectual Property Matters ..................................................................... 4 2.0 OVERVIEW OF WORKS COMPLETED AND INVOLVEMENT OF AUDITOR ............... 6 3.0 SITE INFORMATION ....................................................................................................10 3.1 Site Identification and Location ......................................................................................... 10 3.2 Site Setting ......................................................................................................................... 10 3.3 Site Layout, Topography and Drainage ............................................................................. 11 3.3.1 Site Layout ......................................................................................................... 11 3.3.2 Topography ........................................................................................................ 11 3.3.3 Drainage ............................................................................................................. 11 3.4 Geology ............................................................................................................................. 11 3.5 Hydrogeology .................................................................................................................... 11 3.6 Site History ........................................................................................................................ 12 3.7 Historical Site Contamination Issues ................................................................................. 13 3.8 Proposed Development ...................................................................................................... 14 3.9 Assessment Criteria ........................................................................................................... 14 3.9.1 Soil ..................................................................................................................... 14 3.9.2 Soil Vapour / Ground Gas .................................................................................. 15 3.9.3 Groundwater ....................................................................................................... 16 3.10 Contamination Identified as Requiring Remediation ........................................................ 16 4.0 SUMMARY OF RELEVANT INVESTIGATION WORK ................................................. 17 4.1 Stage 1 Preliminary Investigation (AGEE 1990) .............................................................. 17 4.2 Stage 2 Survey (WWC 1996) ............................................................................................ 17 4.3 Stage 4 Investigations (URS) ............................................................................................. 18 4.3.1 Full Scale Reactive Iron Barrier, Data Gaps Report (URS 2004a) .................... 18 4.3.2 2004 DNAPL Source Area Investigation (URS 2004b) .................................... 18 4.4 Preliminary Soil Investigations (HLA 2005) ..................................................................... 18 4.5 Southern Plumes Source Area Delineation Investigation (URS 2006) ............................. 20 4.6 Shallow Contaminated Soil / Fill Delineation and Waste Management (Golder 2012b) .. 20 4.7 Review of Risk Issues – Groundwater Discharge to Springvale Drain (EnRiskS 2012) .. 22 4.8 Delineation of Remediation Areas (JBS&G 2014c) .......................................................... 23 4.9 Soil Vapour Sampling and Analysis (JBS&G 2015a) ....................................................... 24 4.10 Landfill Gas Monitoring Events and Additional Gas Well Installation Works (JBS&G 2015c) ................................................................................................................................ 26 4.11 Auditor’s Review of Investigations ................................................................................... 27 5.0 AUDITOR’S ASSESSMENT OF THE ADEQUACY OF INVESTIGATION WORK AND REPORTING STANDARDS ...................................................................................................29 5.1 Overview ........................................................................................................................... 29 5.2 Auditor’s Evaluation of Adherence to EPA Guidelines .................................................... 29 6.0 SUMMARY OF PREVIOUS REMEDIATION WORK .................................................... 31 6.1 Excavation Undertaken as part of the Early Works Program (JBS 2014b) ....................... 31 6.2 Soil Hotspot Validation (JBS&G 2015d) .......................................................................... 31 6.2.1 Removal of Vegetation ....................................................................................... 31 6.2.2 Monitoring and Extraction Well Decommissioning .......................................... 32 6.2.3 Air and Environmental Monitoring .................................................................... 32 J1130.23R-rev0 - 4-Aug-15 C. M. Jewell & Associates Pty Ltd ii Site Audit – Suitability of RAP, Part of Block 1 Southlands, 28 McPherson Street, Banksmeadow 6.2.4 Excavation of Hotspots and Stockpiles ............................................................. 32 6.2.5 Stockpiled Materials from the Compensatory Flood Basin ............................... 37 6.2.6 Recycled Materials, Waste Materials Disposed Off‐Site or Placed on Block 2 37 6.2.7 Soil from Block 2 .............................................................................................. 37 6.2.8 Validation Results ............................................................................................. 37 7.0 CONCEPTUAL SITE MODEL AND CONTAMINATION ASSESSMENT ..................... 39 7.1 Topographic Setting .......................................................................................................... 39 7.2 Geology ............................................................................................................................. 39 7.2.1 Regional ............................................................................................................. 39 7.2.2 Local .................................................................................................................. 40 7.3 Hydrogeology ................................................................................................................... 41 7.3.1 Groundwater Flow Regime ............................................................................... 41 7.3.2 Groundwater Levels .......................................................................................... 42 7.3.3 Hydraulic Characteristics .................................................................................. 42 7.4 Groundwater and Surface Water Interaction near the Springvale Drain .......................... 43 7.5 Site Contamination Issues ................................................................................................