94 Mandela Avenue, Klein Windhoek, Namibia PO Box 81808, Windhoek, Namibia Tel: (+264) 61 248 614 Fax: (+264) 61 238 586 Web: www.gcs-na.biz Skorpion Zinc Refinery Sulphide Conversion Amendment to EIA Report Version – Final 25 August 2015 Skorpion Zinc (Pty) Ltd GCS Project Number: 14-756 Client Reference: Order Number - 4100019309 GCS (Pty) Ltd. Reg No: 2006/717 Est.2008 Offices: Durban Johannesburg Lusaka Ostrava Pretoria Windhoek www.gcs-na.biz Director: AC Johnstone Skorpion Zinc (Pty) Ltd Skorpion Zinc Sulphide Conversion Report Version – Final 25 August 2015 Skorpion Zinc (Pty) Ltd 14-756 DOCUMENT ISSUE STATUS Report Issue Final GCS Reference Number 14-756 Client Reference Order Number - 4100019309 Title Skorpion Zinc Refinery Sulphide Conversion AmendmentName to EIA Signature Date Author Eloise Carstens 28 July 2015 Document Reviewer Andrew Johnstone 28 July 2015 Director Andrew Johnstone 28 July 2015 LEGAL NOTICE This report or any proportion thereof and any associated documentation remain the property of GCS until the mandator effects payment of all fees and disbursements due to GCS in terms of the GCS Conditions of Contract and Project Acceptance Form. Notwithstanding the aforesaid, any reproduction, duplication, copying, adaptation, editing, change, disclosure, publication, distribution, incorporation, modification, lending, transfer, sending, delivering, serving or broadcasting must be authorised in writing by GCS. 14-756 25 August 2015 Page ii Skorpion Zinc (Pty) Ltd Skorpion Zinc Sulphide Conversion EXECUTIVE SUMMARY Skorpion Zinc life of mine will end in 2019. This will have an economic impact on both Rosh Pinah and the Namibian economy as a whole. In order to extend the life of the refinery and maintain the design production rate beyond 2019, Skorpion Zinc is planning to treat zinc sulphide concentrates in parallel to the oxide stream from 2017 to 2021. Only thereafter will zinc sulphide be treated, until approximately 2032. The treatment of zinc sulphide (ZnS) concentrate will require modification to the existing refinery facilities. The modification will involve the construction of a sulphide roaster, acid plant and leaching facilities in order to prepare the sulphide ore for refining in the existing plant. The construction of the new facilities will take place in an area of approximately 200 x 200m east of the existing plant in the Accessory Works Area, which is at present a contractor’s yard. In order to obtain regulatory approval Skorpion Zinc will have to amend its current EMP to take into consideration the proposed modifications to the existing processing plant and the disposal of additional waste. Specialist studies have been proposed and will be undertaken to ensure that the amendment to the EMP takes into account and mitigates potential environmental impacts associated with the modification. The construction of the additional processing plant will involve 1000 staff. After the construction phase (and in the operation phase) 24 additional plant operators will be employed in the processing plant. The EMP amendment will consider, amongst other documents, the initial EIA by Walmsely Environmental Consultants (1998), EcoPlan (2000) and the EMP compiled by GCS in 2010. It will also consider the International Finance Corporation (IFC) standards and Vedanta Environmental Management System. The information provided in this report is in accordance to what is required in the Act and the request for amendment will then be submitted to the Environmental Commissioner. 14-756 25 August 2015 Page iii Skorpion Zinc (Pty) Ltd Skorpion Zinc Sulphide Conversion CONTENTS PAGE 1.1 BACKGROUND ............................................................................................................................... 1 1.2 CONDITIONS ON THE CURRENT CLEARANCE CERTIFICATE ........................................................................ 2 1.3 PROJECT LOCATION ........................................................................................................................ 2 1.4 RATIONALE ................................................................................................................................... 4 2.1 PROJECT OVERVIEW ....................................................................................................................... 4 2.2 PROPOSED PLANT MODIFICATIONS: THE SULPHIDE CIRCUIT .................................................................... 8 2.2.1 Bulk handling and storage of Sulphide Zinc concentrate ore ............................................ 9 2.2.2 The construction of a roasting circuit with gas cleaning plant and gas recovery acid plant 9 2.2.3 The installation and integration of a new calcine leach circuit with the existing equipment ....................................................................................................................................... 10 2.3 WASTE AND BYPRODUCT STREAMS ................................................................................................. 12 2.3.1 Air emissions ................................................................................................................... 12 2.3.2 Waste and by-products ................................................................................................... 12 2.3.3 Tailings and Tailings Storage Facility .............................................................................. 14 2.3.4 Waste Rock Stockpile and TSF Requirements ................................................................. 15 2.4 RESOURCE AND INFRASTRUCTURE REQUIREMENTS.............................................................................. 16 2.5 POTENTIAL ENVIRONMENTAL IMPACTS ARISING FROM THE PROPOSED PLANT MODIFICATIONS ..................... 17 3.1 OVERVIEW ................................................................................................................................. 18 3.2 CLIMATIC CONDITIONS .................................................................................................................. 19 3.2.1 Rainfall and Temperature ............................................................................................... 19 3.2.2 Wind................................................................................................................................ 19 3.2.3 Ambient Air Quality ........................................................................................................ 23 3.3 TOPOGRAPHY, GEOLOGY AND SOILS ................................................................................................. 23 3.4 GROUNDWATER .......................................................................................................................... 25 3.5 SOCIO-ECONOMIC STATUS ............................................................................................................. 25 3.5.1 Karas Region ................................................................................................................... 25 3.5.2 Rosh Pinah ...................................................................................................................... 26 3.5.3 Skorpion Zinc Mine.......................................................................................................... 26 4.1 INTRODUCTION ........................................................................................................................... 27 4.2 PUBLIC CONCERNS ....................................................................................................................... 30 4.3 PUBLIC FEEDBACK ........................................................................................................................ 30 5.1 KEY ENVIRONMENTAL IMPACTS ....................................................................................................... 31 5.2 METHODOLOGY FOR ASSESSMENT ................................................................................................... 31 5.3 IMPACT ON AIR QUALITY, HUMAN AND ANIMAL HEALTH AND VEGETATION .............................................. 33 5.3.1 Description ...................................................................................................................... 33 5.3.2 Type of Pollutants ........................................................................................................... 34 5.3.3 Sources of emissions ....................................................................................................... 35 5.3.4 Impacts of particulates and gas emissions on humans, animals and vegetation ........... 39 5.3.5 Mitigation ....................................................................................................................... 39 5.4 IMPACT ON GROUNDWATER AND SOIL .............................................................................................. 42 5.4.1 Description ...................................................................................................................... 42 5.4.2 Acid Generating Potential ............................................................................................... 42 5.4.3 Neutralization capacity of the limestone with the calcine leach residue ........................ 42 5.4.4 Metals ............................................................................................................................. 43 5.4.6 Limestone ratios ............................................................................................................. 44 5.5 IMPACT ON THE