WAMBO COAL EROSION AND SEDIMENT CONTROL PLAN Document No. WA-ENV-MP-509.3 April 2018 Document Control Document No. WA-ENV-MP-509.3 Title Erosion and Sediment Control Plan General Description Management of erosion and sediment impacts at WCPL Document Owner Environment & Community Manager Revisions Rev No Date Description By Checked Signature Gilbert & Associates 0 June 2005 Original Draft JT/TS Pty Ltd Gilbert & Associates 1 July 2005 Revised Draft JT/TS Pty Ltd Gilbert & Associates 2 July 2005 Final Draft JT/TS Pty Ltd Management Plan 3 February 2006 WCPL JT/JH Consolidation Management Plan 4 August 2007 Hansen Bailey SW Consolidation Consent 5 February 2010 WCPL SB Modification 6 September 2014 Revision 6 WCPL TF New plan format 7 October 2015 WCPL/Palaris SP and revision Revised as required 8 April 2016 by Con 6, Sch 3 of WCPL SP DA305-7-2003 Revised as required by Con 6, Sch 3 of DA305-7-2003 and 9 March 2018 MOD17 approval, WCPL PJ include Summary Of Commitments Revised to address 10 April 2018 WCPL DP&E Comments Erosion and Sediment Control Plan WA-ENV-MP-509.3 Version: 10 Uncontrolled when printed CONTENTS 1.0 INTRODUCTION ...........................................................................................................1 1.1 BACKGROUND .........................................................................................................1 1.2 PURPOSE..................................................................................................................3 1.3 SCOPE ......................................................................................................................3 1.4 STATUTORY REQUIREMENTS ...............................................................................6 1.5 STAKEHOLDER CONSULTATION ........................................................................... 8 2.0 POTENTIAL SOURCES AND IMPACTS ..................................................................... 9 3.0 OVERVIEW .................................................................................................................10 3.1 SITE WATER MANAGEMENT ................................................................................10 3.2 SOILS ......................................................................................................................10 3.3 SLOPE .....................................................................................................................11 3.4 HYDROLOGY ..........................................................................................................11 4.0 PLANNING .................................................................................................................12 4.1 PRINCIPLES ............................................................................................................12 4.2 EROSION & SEDIMENT CONTROL IMPLEMENTATION PLAN ............................ 13 5.0 EXISTING CONTROLS ..............................................................................................19 5.1 DESIGN GUIDELINES .............................................................................................22 6.0 IMPLEMENTATION ....................................................................................................25 6.1 CONSTRUCTION ....................................................................................................25 6.2 SEDIMENT FENCES ...............................................................................................25 6.3 CHECK DAMS .........................................................................................................25 6.4 DIVERTED WATER MANAGEMENT ...................................................................... 26 6.5 SURFACE WATER MANAGEMENT .......................................................................26 6.6 WORKED WATER MANAGEMENT SYSTEM ........................................................ 28 6.7 TOPSOIL MANAGEMENT .......................................................................................29 6.8 SUBSIDENCE MANAGEMENT ...............................................................................29 6.9 PERFORMANCE INDICATORS ..............................................................................29 7.0 INSPECTIONS, MONITORING AND MAINTENANCE .............................................. 31 7.1 ALL CONTROL STRUCTURES ...............................................................................31 7.2 SEDIMENT CONTROL DAMS .................................................................................31 8.0 COMMUNITY COMPLAINT RESPONSE ...................................................................32 9.0 REVIEW AND REPORTING .......................................................................................33 Erosion and Sediment Control Plan WA-ENV-MP-509.3 Version: 10 Uncontrolled when printed i 9.1 REVIEW ...................................................................................................................33 9.2 ANNUAL REVIEW ...................................................................................................33 9.3 WEBSITE UPDATES ...............................................................................................33 9.4 REPORTABLE ENVIRONMENTAL INCIDENTS ..................................................... 34 10.0 RESPONSIBILITIES ...................................................................................................35 11.0 REFERENCES ............................................................................................................36 Erosion and Sediment Control Plan WA-ENV-MP-509.3 Version: 10 Uncontrolled when printed ii Tables Table 1: Summary of the Approved Wambo Coal Mine ........................................................... 1 Table 2: Development Consent Requirements for the Erosion and Sediment Control Plan .... 6 Table 3: Sources of Erosion and Sedimentation ...................................................................... 9 Table 4: Sediment Dam Risk Analysis ...................................................................................17 Table 5: Water Management Control Structures ................................................................... 19 Table 6: Design Guidelines for Sediment Control .................................................................. 22 Table 7: Guidelines for Erosion Control ................................................................................. 23 Table 8: Summary of Erosion Control Techniques ................................................................ 24 Table 9: Performance Indicators ............................................................................................ 30 Table 10: Erosion and Sediment Control Plan Responsibilities ............................................. 35 Figures Figure 1: Wambo Coal Regional Location ...............................................................................2 Figure 2: WCPL Site Water Management Plan .......................................................................3 Figure 3: Approved Wambo Coal Mine Layout ........................................................................ 5 Figure 4: Erosion and Sediment Control Matrix (Peabody, 2014) ......................................... 18 Figure 5: Water Management Structures ...............................................................................21 Figure 6: Example of Sediment Fencing ................................................................................ 25 Figure 7: Example of Check Dams ........................................................................................26 Figure 8: 5-Day Rainfall Depth ............................................................................................... 27 Figure 9: Settling and Storage Zones ....................................................................................28 Figure 10: Indicative Sediment Dam Capacity .......................................................................28 Figure 11: Indicative Pump Out Time Frames ....................................................................... 28 LIST OF APPENDICES Appendix A Consultation with Regulatory Authorities Appendix B Dispute Resolution Process Appendix C Wambo Coal Surface Disturbance Permit Appendix D Design Principles Appendix E Sediment Control Structure Inspection Checklist Appendix F Example of Certification of Sediment Dam Construction Appendix G Risk Assessment Matrix Appendix H Summary of Commitments Erosion and Sediment Control Plan WA-ENV-MP-509.3 Version: 10 Uncontrolled when printed iii 1.0 Introduction 1.1 Background The Wambo Coal Mine (the Mine) is situated approximately 15 kilometres west of Singleton, near the village of Warkworth, New South Wales (Figure 1). The Mine is owned and operated by Wambo Coal Pty Limited (WCPL), a subsidiary of Peabody Energy Australia Pty Limited. A range of open cut and underground mine operations have been conducted at WCPL since mining operations commenced in 1969. Mining under the current Development Consent (DA 305-7-2003) commenced in 2004 and permits both open cut, underground operations and associated activities to be conducted. The approved run-of-mine (ROM) coal production rate is 14.7 million tonnes per annum and all product coal is transported from WCPL by rail. A summary of the approved Wambo Coal Mine is provided in Table 1. Table 1: Summary of the Approved Wambo Coal Mine Component Approved Wambo Coal Mine1,2 Life of Mine Wambo Coal may carry out mining operations at the