Erosion and Sediment Control Assessment Report Rev. 0 This is an uncontrolled copy if photocopied or printed from the Intranet. Copyright © 2016, SouthernSkies Environmental Ltd. All rights reserved. Page 4 of 30 1. INTRODUCTION This Erosion and Sediment Control Assessment Report (ESCAR) provides: • the overarching erosion and sediment control (ESC) principles and procedures for the earthwork activities associated with the OceanaGold New Zealand Ltd (OGNZL) Waihi North Project (the Project); • an assessment of the effectiveness of those ESC principles and procedures in minimising potential sediment discharges to an acceptable level; and • concepts that inform the development of the Site Specific Erosion and Sediment Control Plans (SSESCPs). It is to be read in conjunction with the following appended documents: • Chemical Treatment Management Plan (CTMP); • Erosion and Sediment Control Monitoring Plan; and • SSESCPs. The ESCAR and supporting documents address the management of soils and non-acid forming (NAF) soils that are to be exposed and placed during the Project development (for example site establishment works and NAF stockpiling). Runoff from all potential acid forming (PAF) material will be directed to the existing Water Treatment Plant. That runoff is acknowledged in this ESCAR but is not assessed. Prior to earthworks commencing in each area, the corresponding SSESCP will be finalised and provided to Waikato Regional Council (WRC) for certification as required by the conditions of consent. This approach allows for flexibility, fine tuning and ownership of the ESC measures and methodologies by the project manager. 2. PROJECT DESCRIPTION 2.1. Overview The Project represents the further development of the mineral resources in the Waihi Epithermal District. It comprises the following components (see Figures 1 to 5 below): • Wharekirauponga Underground Mine (WUG): o A new underground mine at Wharekirauponga, with associated surface infrastructure located on farmland (owned by OGNZL) at Willows Road. o Underground access to dual tunnels extending to the Wharekirauponga orebody and a connecting tunnel from the dual tunnels to the existing Processing Plant at Waihi. o Vent shafts located at points along the tunnels to the ore body. • Gladstone Open Pit (GOP): o A new open pit to the west of the Processing Plant, with associated infrastructure. This will require the relocation of the Martha Underground (MUG) portal, with the new portal opening also providing access to WUG (WUG portal). • Tailings Storage Facility 3 (TSF3): o A new tailing storage facility impoundment located to the east of the existing TSF1A tailings pond, constructed to crest height of 155m RL. • Northern Rock Stack (NRS): o A new rock storage facility to be established north of existing TSF2.
RkJQdWJsaXNoZXIy MjE2NDg3