1.2 Potential Surface Water Impacts As the mine plan for the Revised Project is not predicted to result in any subsidence there will be no new impacts on the surface catchments and streams above the proposed mine workings. As such, the scope of this Surface Water Impact Assessment (SWIA) has been limited to the Russell Vale Surface Facilities (Surface Facilities) (refer to Figure 1.3). The following are the key aspects of the Revised Project that have the potential to impact on surface water resources: • restoration and upgrade of Surface Facility Water Management System (WMS) infrastructure • changes to the water balance associated with the Revised Project, and • discharges to surface waters. The key aspects listed above have the potential to impact on the following surface water characteristics: • flow volumes in downstream watercourses • flooding, including flow rates, velocities and depths • water quality in downstream watercourses • geomorphological and hydrological values of watercourses, including environmental flows • riparian and ecological values of watercourses, and • water users, both in the vicinity and downstream of the Surface Facilities. An assessment of these potential impacts has been undertaken for the Revised Project (refer to Section 6.0). 1.3 Report Structure The key components of the SWIA for the Revised Project are included in the following sections: • Surface water context, including regulatory framework, existing watercourses, catchment context and water quality: Section 2.0. • Existing WMS and Proposed WMS: Section 3.0. • Water balance: Section 4.0. • Predicted impacts of the Revised Project, including consideration of cumulative impacts: Section 6.0. • Summary of mitigation and management measures: Section 6.0. • Monitoring, licensing and reporting: Section 7.0. Surface Water Impact Assessment Introduction 3687_R09_SWIA_Final 13 2.0 Surface Water Context 2.1 Regulatory Framework 2.1.1 Water Extraction Extraction of water in NSW is managed under two legislative acts: Water Act 1912 (Water Act) and Water Management Act 2000 (WM Act). The objective of the WM Act is the sustainable and integrated management of water in NSW and is based on the concept of ecologically sustainable development by defining water access and water sharing strategies within NSW. The WM Act supersedes the provisions of the Water Act in regard to water take when a Water Sharing Plan (WSP) is in place and in regards to works adjacent to or within watercourses. Where WSPs have not commenced the provisions of the Water Act continue to apply. WSPs have been developed across NSW to protect the fundamental environmental health of water sources, whilst at the same time securing sustainable access to water for all users in the long-term. The WSPs specify maximum water extractions and allocations and provide water users with a clear picture of when and how water will be available for extraction. The Russell Vale Colliery Pit Top facilities are located within the area regulated by the WSP for the Greater Metropolitan Region Unregulated River Water Sources. Water use from surface and alluvial waters in and adjacent to the Surface Facilities is therefore governed by the WM Act. 2.1.1.1 Licensing of Extraction All water extraction in NSW, apart from some exemptions for government authorities and basic landholder rights extractions, must be authorised by a water licence. Harvestable rights, which are a basic landholder right under the WM Act allow a landholder to capture and use up to 10% of the average regional runoff from a landholding. Basic landholder rights are exempt from volumetric licensing requirements however water extracted under basic landholder rights must be taken into consideration when assessing licensing requirements. Each water licence, referred to under the WSP system as a Water Access Licence (WAL), specifies a share component. The share components of specific purpose licences such as local water utility, major utility and domestic and stock are expressed as a number in megalitres (ML) per year. The share components of high security, general security and supplementary WALs are expressed as a number of unit shares for the water source. The value of each unit share is subject to Available Water Determinations (AWDs) as specified by the Department of Industry – Water (DoI Water). There are currently no WALs related to surface or alluvial water held by WCL. 2.1.2 Environment Protection Licences and Discharges The Protection of the Environment Operations Act 1997 (POEO Act) is a key piece of environment protection legislation in NSW. Scheduled activities or other activities that do or may lead to pollution of waters (refer to Section 120 of the POEO Act) in NSW are required to be licensed under the POEO Act and are regulated by the NSW Environment Protection Authority (EPA). Where discharge of water is permitted, it is strictly controlled by licence conditions such that discharges do not result in significant impacts on water resources. Surface Water Impact Assessment Surface Water Context 3687_R09_SWIA_Final 14 Under Section 120 of the POEO Act, it is an offence to pollute waters or cause harm unless licensed to do so. Pollution in NSW is regulated by the POEO Act with discharges from mine water management systems requiring licensing by an Environment Protection Licence (EPL) if the discharge would otherwise constitute a pollution of waters (Section 120 of the POEO Act). Coal mining and coal works are scheduled activities and WCL holds an EPL (EPL 12040) which licenses these activities at the Russell Vale Colliery, including four existing licensed water discharge points (LDPs), three of which are relevant to the Revised Preferred Project (Figure 2.3) and this SWIA (4th LDP is outside Revised Preferred Project boundary), and two ambient water quality monitoring points (Figure 2.3). The relevant EPL discharge and monitoring points are presented in Section 2.3.4.2. 2.1.3 Existing Project Approval The most recent existing project approval includes a range of conditions relating to surface water management. A list of the existing project approval conditions relevant to the SWIA are presented in Appendix A. 2.2 Project Assessment Requirements Director General’s Requirements (DGRs) for the UEP were originally issued in 2009. As such this SWIA has been prepared to address the DGRs and to respond to agency submissions relevant to surface water resources for the Revised Preferred Project. Table 2.1 presents the 2009 DGRs, relevant agency submissions and the section within this SWIA where the assessment requirement is addressed. As part of the updated environmental assessment for the Revised Project and Response to the PAC Second Review Report, a detailed groundwater impact assessment has been prepared by GeoTerra and is provided in full in Appendix 2 of the environmental assessment report. A Section 75W Modification to Project Approval MP10_0046 for the Russell Vale Colliery Preliminary Works Project was submitted in March 2018 (Modification 4 (MP 10_0046 MOD 4)) seeking approval to retain the existing Bellambi Gully Diversion Pipeline (refer to Section 3.2.1). A Further Response to Agency Submissions has been submitted in June 2019. Table 2.1 Assessment Requirements Requirement/Submission Section Addressed Director General’s Requirements Soil and Water – including: - A detailed assessment of the potential impacts of the Revised Project on Refer to Sections 1.2, 2.1.1, the quantity, quality and long-term integrity of the surface and ground 3.0, 4.0 and 6.0 of this report. water resources in the project area, paying particular attention to the Upper Nepean River sub-catchment (Metropolitan Special Area), the discharge of mine water and the surface runoff into the Bellambi Gully Creek and Bellambi Lagoon - Site water balance, including a detailed description of the measures that Refer to Section 4.0 would be implemented on site to minimise the water use of the Revised Project Surface Water Impact Assessment Surface Water Context 3687_R09_SWIA_Final 15 Requirement/Submission Section Addressed PAC Second Review Report S 4.7 Bellambi Creek - Flood Management Refer to Part B, Section 14 of The Commission is satisfied that the issue raised in the First Review Report has the Revised Preferred Project been adequately addressed and supports, if the project were to be approved, and Response to PAC Second the inclusion of a condition of consent that requires the implementation of Review Report. flood mitigation measures recommended in the Cardno 2015 Report within 12 months of the date of approval. It also supports the draft recommended condition requiring the installation of a swale alongside the stockpile access road, which should improve water management on the site, though it is noted that the discharge of dirty water from the site is regulated by the EPA under the site’s EPL. 2.3 Catchment Context 2.3.1 Topography and Drainage The Surface Facilities are located approximately 8 km north of Wollongong within the catchment of Bellambi Gully Creek on the lower slopes and foothills of the Illawarra Escarpment (refer to Figure 2.1). The escarpment is characterised by steep heavily vegetated slopes and reaches up to an elevation of 400 mAHD (BECA, 2011) descending to foothills at approximately 30 mAHD. The underground lease lies to the west of the surface facilities and escarpment under the Woronora Plateau. Runoff originating from the escarpment flows toward the Surface Facilities where some sections of Bellambi Gully Creek have been replaced