SECTION 4 ENVIRONMENTAL ASSESSMENT COWAL GOLD MINE EXTENSION MODIFICATION Cowal Gold Mine Extension Modification – Environmental Assessment TABLE OF CONTENTS 4 ENVIRONMENTAL ASSESSMENT 4-1 LIST OF TABLES 4.1 HYDROGEOLOGY 4-1 Table 4-1 Groundwater Licensing Requirement 4.1.1 Existing Environment 4-1 Summary 4.1.2 Potential Impacts 4-7 Table 4-2 Native Vegetation 4.1.3 Mitigation Measures and Management 4-12 Table 4-3 Broad Fauna Habitat Type 4.2 SURFACE WATER 4-13 Table 4-4 Threatened Fauna Species 4.2.1 Existing Environment 4-13 Table 4-5 Existing Impact Mitigation Measures at 4.2.2 Potential Impacts 4-16 the CGM 4.2.3 Mitigation Measures, Table 4-6 Native Vegetation Clearance Management and Monitoring 4-17 Table 4-7 Quantification of Broad Fauna Habitat 4.3 FLORA AND FAUNA 4-18 Types and Vegetation Communities 4.3.1 Existing Environment 4-18 within the Modification Area and Offset 4.3.2 Potential Impacts 4-29 Area 4.3.3 Mitigation Measures and Table 4-8 Quantification of Threatened Management 4-32 Ecological Communities within the 4.3.4 Biodiversity Offset Strategy 4-32 Modification Area and Offset Area 4.4 ABORIGINAL CULTURAL HERITAGE Table 4-9 Reconciliation of the Proposed ASSESSMENT 4-36 Biodiversity Offset Strategy against OEH Offset Principles 4.4.1 Existing Environment 4-36 4.4.2 Potential Impacts 4-42 Table 4-10 Summary of Aboriginal Heritage Consultation Programme 4.4.3 Mitigation Measures and Management 4-43 Table 4-11 Items Identified During 30 April to 3 May 2013 Survey 4.5 NOISE 4-44 4.5.1 Existing Environment 4-44 Table 4-12 Predicted Intrusive Noise Levels for the Currently Approved CGM and the 4.5.2 Potential Impacts 4-47 CGM Incorporating the Modification 4.5.3 Mitigation Measures, Management and Monitoring 4-49 Table 4-13 Summary of Privately-Owned Receivers in Noise Management and 4.6 AIR QUALITY 4-50 Noise Affectation Zones 4.6.1 Existing Environment 4-50 Table 4-14 Typical Visual (Viewer) Sensitivity 4.6.2 Potential Impacts 4-50 Levels 4.6.3 Mitigation Measures, Table 4-15 Visual Impact Matrix Management and Monitoring 4-51 4.7 LAND RESOURCES 4-51 Table 4-16 Visual Impact Assessment Summary 4.7.1 Existing Environment 4-51 4.7.2 Potential Impacts 4-53 LIST OF FIGURES 4.7.3 Mitigation Measures and Management 4-55 Figure 4-1 ML 1535 Surface Water and 4.8 VISUAL CHARACTER 4-55 Groundwater Monitoring Locations 4.8.1 Existing Environment 4-55 Figure 4-2 Conceptual Hydrological Cross 4.8.2 Potential Impacts 4-59 Section across ML 1535 4.8.3 Mitigation Measures and Management 4-81 Figure 4-3 Predicted Maximum Watertable Drawdown Contours at the end of the 4.9 SOCIO-ECONOMICS 4-82 Modification 4.10 OTHER ENVIRONMENTAL ASPECTS 4-83 Figure 4-4 Predicted Watertable Drawdown with 4.10.1 Road Transport 4-83 the Bland Creek Palaeochannel 4.10.2 Greenhouse Gas Emissions 4-84 Borefield pumping at 7.2ML/day during 4.10.3 Blasting 4-84 the Modification 4.10.4 Road Traffic Noise 4-85 Figure 4-5 Vegetation Communities within the 4.10.5 Non-Aboriginal Heritage 4-85 Wider Locality 4.10.6 Hazard and Risk 4-85 Figure 4-6 Vegetation Communities within the Modification Area and Surrounds Figure 4-7 Fauna Habitat Types 4-i Cowal Gold Mine Extension Modification – Environmental Assessment TABLE OF CONTENTS (continued) LIST OF FIGURES (Continued) LIST OF FIGURES (Continued) Figure 4-8 Threatened Fauna Species recorded Figure 4-22a Existing View and Visual Simulations within the Modification Area and – “Cowal North” Dwelling Surrounds Figure 4-22b Existing View and Visual Simulations Figure 4-9 Existing and Proposed Offset Areas – “Cowal North” Dwelling Figure 4-10 Aboriginal Heritage Sites Located Figure 4-23a Existing View and Visual Simulations within the Modification Area and – Pubic Laneway Surrounds Figure 4-23b Existing View and Visual Simulations Figure 4-11 Aboriginal Heritage Sites Located in – Public Laneway Proximity to the Eastern Pump Station and Existing Water Pipeline Alignment Figure 4-12a Predicted Noise Contours Night-time Inversion (2015) Figure 4-12b Predicted Noise Contours Night-time Inversion (2017) Figure 4-13 24-Hour Average PM10 Concentrations – Year 11 – Cowal Gold Mine Incorporating the Modification Only Figure 4-14 Cowal Gold Mine Location and Visual Simulation Locations Figure 4-15a Existing View and Visual Simulations – “Gumbelah” Dwelling Figure 4-15b Existing View and Visual Simulations – “Gumbelah” Dwelling Figure 4-16a Existing View and Visual Simulations – “Coniston” Dwelling Figure 4-16b Existing View and Visual Simulations – “Coniston” Dwelling Figure 4-17a Existing View and Visual Simulations – “Westlea” Dwelling Figure 4-17b Existing View and Visual Simulations – “Westlea” Dwelling Figure 4-18a Existing View and Visual Simulations – Lake Cowal Road North of Cowal Gold Mine Figure 4-18b Existing View and Visual Simulations – Lake Cowal Road North of Cowal Gold Mine Figure 4-19a Existing View and Visual Simulations – Lake Cowal Road West of Cowal Gold Mine Figure 4-19b Existing View and Visual Simulations – Lake Cowal Road West of Cowal Gold Mine Figure 4-20a Existing View and Visual Simulations – Lake Cowal Road South of Cowal Gold Mine Figure 4-20b Existing View and Visual Simulations – Lake Cowal Road South of Cowal Gold Mine Figure 4-21a Existing View and Visual Simulations – “Lakeview” Dwelling Figure 4-21b Existing View and Visual Simulations – “Lakeview” Dwelling 4-ii Cowal Gold Mine Extension Modification – Environmental Assessment 4 ENVIRONMENTAL ASSESSMENT • Cowal Gold Mine – Groundwater Level Investigation (Coffey Geotechnics, 2009a); and 4.1 HYDROGEOLOGY Cowal Gold Mine – E42 Modification Modified • (Coffey Geotechnics, 2009b). A Hydrogeological Assessment for the Modification Request was conducted by Coffey Geotechnics (2013) and is presented in Appendix A. The Hydrogeological A comprehensive review of existing geological and Assessment was peer reviewed by Dr Frans Kalf hydrogeological information, as well as relevant (Kalf and Associates), an internationally recognised monitoring data and mapping, was undertaken by hydrogeological expert (Attachment 3). Coffey Geotechnics (2013), including evaluation of the following: The Hydrogeological Assessment and Hydrological previous hydrogeological investigations (listed Assessment (prepared by Gilbert & Associates • above); [2013] [Appendix B]) have been conducted in an integrated manner (e.g. predicted groundwater • data collected from the existing CGM inflow to the open pit has been included in the groundwater monitoring network in Hydrological Assessment’s site water balance). accordance with the existing Site Water Management Plan, and the Surface Water, 4.1.1 Existing Environment Groundwater, Meteorological and Biological Monitoring Programme; Baseline Groundwater Data • information on local water bores and groundwater usage in the vicinity of the CGM, A significant number of hydrogeological studies and including NOW monitoring bores; site testwork have been conducted for the CGM area and surrounds, including: • publicly available regional geological data; • detailed local geological data held by Barrick; • Lake Cowal Project – Laboratory Testing of and Tailings (Knight Piesold Pty Ltd, 1994); • geographic information including aerial • Lake Cowal Project Hydrogeological Modelling photography, satellite imagery, digital and Dewatering Study (Coffey Partners elevation models, geophysical, cadastral and International Pty Ltd [Coffey Partners hydrological data sets. International], 1995); • the EIS, which included the Groundwater Existing groundwater monitoring locations, including Studies – Hydrogeological Assessment for the Bland Creek Palaeochannel, are shown on (Coffey Partners International, 1997) and Figure 2-3 and Figure 4-1. Groundwater Studies – Pre-assessment Groundwater Issues (Kalf and The Hydrogeological Assessment has considered Associates, 1997); the requirements of relevant Water Sharing Plans listed under the NSW Water Management • Cowal Northern Tailings Storage Facility Act, 2000. – Floor Permeability (URS Australia Pty Limited, 2005); Existing Groundwater Regime • Cowal Southern Tailings Storage Facility The Water Sharing Plans relevant to the CGM – Floor Permeability (URS Australia Pty include the Water Sharing Plan for the Lachlan Limited, 2006); Unregulated and Alluvial Water Sources 2012 and • Cowal Gold Project – Preliminary the Water Sharing Plan for the NSW Murray Darling Hydrogeochemical Review of the Groundwater Basin Fractured Rock Groundwater Sources 2011. System (Parsons Brinckerhoff Australia Pty Ltd, 2007); • Cowal Gold Mine E42 Modification Hydrogeological and Tailings Seepage Assessment (Coffey Geotechnics, 2008); 4-1 Cowal Gold Mine Extension Modification – Environmental Assessment A conceptual groundwater model of the existing Existing Effects of Mining Activities at the CGM groundwater regime was developed by Coffey Geotechnics (2013) based on review of available Groundwater Inflows to the Open Pit and Open Pit hydrogeological data to support the two Dewatering groundwater systems identified in the relevant Water Sharing Plans, which are as follows: Groundwater inflow to the open pit is managed by dewatering bores in pit sumps (which also collect • alluvial groundwater system; and incidental rainfall). A ring of 14 dewatering bores currently operate to control groundwater levels • fractured rock groundwater system. around the open pit. Horizontal drains in the pit wall Alluvial Groundwater System accelerate depressurisation of the aquifer system by draining groundwater into the pit sumps. Alluvial