Oyu Tolgoi Mine Closure Plan
Total Page:16
File Type:pdf, Size:1020Kb
OYU TOLGOI MINE CLOSURE PLAN PREPARED BY AMEC ENVIRONMENT & INFRASTRUCTURE, A DIVISION OF AMEC AMERICAS LIMITED FOR OYU TOLGOI LLC Project No.: 172472 Issue Date: 14 June 2012 Revision Date: April 2014 IMPORTANT NOTICE This report was prepared exclusively for Oyu Tolgoi LLC (OT LLC) by AMEC Environment & Infrastructure, a wholly owned subsidiary of AMEC Americas Limited. The quality of information, conclusions and estimates contained herein is consistent with the level of effort involved in AMEC services and based on: i) information available at the time of preparation, ii) data supplied by outside sources, and iii) the assumptions, conditions and qualifications set forth in this report. This report is intended for use by Oyu Tolgoi LLC only, subject to the terms and conditions of its contract with AMEC. Any other use of, or reliance on, this report by any third party is at that party’s sole risk. Prepared by: Caius Priscu, Ph.D, P.Eng AMEC Environment & Infrastructure Oyu Tolgoi Mine Closure Plan Lead Reviewed by: Tom Tangen AMEC Environment & Infrastructure Senior Reviewer Approved by: Andy Gillam, Ph.D, P.Geo AMEC Environment & Infrastructure Project Manager Updated by: James Addison, P.Eng. AMEC Mining & Metals Oyu Tolgoi Project Engineer Reviewed by: David Bleiker AMEC Environment & Infrastructure Senior Reviewer Approved by: Bruce Williams AMEC Mining & Metals Project Manager O YU T OLGOI M INE C LOSURE P LAN OYU TOLGOI LLC DISTRIBUTION LIST Web / Email Copies Distributed: William Scheding – OT LLC Mark Newby – OT LLC Brandon Swanepoel – OT LLC Joergen Pilz – RT Rich Borden - RT Blair Sands – RT David Bleiker – AMEC Bruce Williams – AMEC Laurie Reemeyer – AMEC Scott Macklin - AMEC James Addison – AMEC AMEC File: 2.8.10 AMEC File: 2.8.10 O YU T OLGOI M INE C LOSURE P LAN OYU TOLGOI LLC EXECUTIVE SUMMARY This document presents the 2014 update to the Closure Plan for the Oyu Tolgoi (OT) Project, located approximately 550 km south of Ulaanbaatar, Mongolia, and 80 km north of the border with China. The mining license is held by Oyu Tolgoi LLC, a partnership between Ivanhoe Mines, Rio Tinto and the Government of Mongolia. At this stage, the OT copper-gold mine is operational, with mining activities having started in 2013 and ramping up to 110,000 t/d ore production. Current planned closure of the mill is scheduled to take place, at this time, in 2055. This Order of Magnitude closure study level addresses closure of all aspects related to the current 42-year mine life, as described in the OTFS14. However, given the known mineralization in the area it is likely that mine life will extend significantly beyond 2055. The over-arching objectives of this Closure Plan are to develop and document mine closure strategies as early in the project as possible in order to protect public health and safety, meet Rio Tinto Standards, and to avoid or mitigate potential environmental and social impacts associated with the site closure. The closure strategies have been prepared to ensure they are compliant with Rio Tinto corporate standards and guidelines, as well as relevant Mongolian and International standards, guidelines and directives. The proposed closure and rehabilitation measures ensure site-specific issues of concern are identified and addressed, to manage and mitigate associated risks. This Closure Plan presents closure measures for temporary closure due to unexpected conditions, as well as proposed progressive rehabilitation measures that can be implemented concurrent with the operations. In summary, the proposed mine closure and rehabilitation program includes the following key measures and activities: Removal and appropriate disposal of all wastes, chemicals, reagents and materials from both surface and underground; Capping of all underground openings to surface (shafts and raises); Demolition and removal of all surface infrastructure, with potential opportunities to maximize salvage and recycling of acceptable materials (structural steel, etc); Disposal of all inert demolition material and wastes into the open pit, in an engineered landfill; Clean-up of the mine yard areas, removal of any impacted soils to the landfill, and recontouring the areas to match surrounding topography; Encapsulation of potentially acid-forming waste rock with non-acid-forming material; Project No.: 172472 Issue Date: April 2014 i O YU T OLGOI M INE C LOSURE P LAN OYU TOLGOI LLC Construction of engineered soil or growth media covers over the waste rock dumps and tailings storage facility that would promote positive drainage and non-erosive run-off, minimize infiltration, minimize aeolian erosion, and support a vegetative cover; Covering disturbed areas with topsoil/growth media, with the aim to return land to conditions suitable for nomadic herdsman and their grazing animals; Construction of a safety berm around the open pit and the subsidence area to limit to the greatest extent possible the potential for public access; Implementation of remedial measures such that they minimize long-term maintenance at the site; and Implementation of a post-closure monitoring program that will ensure physical and chemical stability of the project area and associated facilities that will remain at the site. Directing of any contaminated runoff and seepage water to the open pit where permanent containment will be maintained due to evaporative losses. The Closure Plan includes a number of proposed community and socio-economic initiatives to be implemented as the project transitions from operations to closure and post-closure. All of these initiatives will adhere to the regulatory requirements of the Government of Mongolia, as well as industry best practices performance standards and requirements, and the Rio Tinto Closure Standard. A number of community and regional development plans, programs, investments, and other social and economic initiatives are proposed in Khanbogd and other neighboring soums in Omnogovi aimag, with full participation of local communities, NGOs and other key stakeholders in the OT Project Area of Influence. These initiatives are intended to address anticipated community, wellbeing, social, economic, cultural heritage and environmental effects during the life cycle of the project. The overall schedule for the Closure Plan spans the entire project timeline and includes: Progressive rehabilitation activities during the mine operation; A 5-year pre-closure period for detailed engineering, planning and design of the closure activities and initiatives (decommissioning plan), starting in 2050; Project No.: 172472 Issue Date: April 2014 ii O YU T OLGOI M INE C LOSURE P LAN OYU TOLGOI LLC A 5-year closure implementation period, starting in 2055; A 10-year post-closure implementation period, to closely monitor the physical and chemical stability of the site, starting in 2060; and A 40-year long-term monitoring period, from 2070 to 2110, to confirm the successful implementation of the closure measures; at the end of this time period, a re- evaluation of the site conditions and monitoring requirements will be conducted. The overall cost of the closure and rehabilitation program of the Oyu Tolgoi mine site and associated socio-economic initiatives is estimated at $1,178 million (Q4 2013 US dollars). A contingency allowance of 25% has been included in this closure cost estimate to reflect the level of detail in closure planning at this point in time and to account for unexpected changes in estimates, as more detailed project information becomes available. This Closure Plan is a “living document” and is intended to be assessed annually to support a realistic closure cost estimate which is reported annually. The Closure Plan will undergo periodic reviews and updates every five years as per Rio Tinto standards and guidelines. Assessments, updates, reviews and amendments are needed in the future in order to reflect changes in mine plans, site conditions, as well as socio-economic context in the region. Project No.: 172472 Issue Date: April 2014 iii O YU T OLGOI M INE C LOSURE P LAN OYU TOLGOI LLC CONTENTS EXECUTIVE SUMMARY ......................................................................................................... I 1.0 INTRODUCTION ........................................................................................................ 1 1.1 Purpose and Objectives of the Closure Plan .................................................. 1 1.2 Closure Plan Scope ....................................................................................... 1 1.3 Report Outline ................................................................................................ 2 1.4 Closure Plan Reviews and Updates ............................................................... 3 2.0 CERTIFICATION ........................................................................................................ 5 2.1 Certification by Proponent .............................................................................. 5 2.2 Letter of Confirmation of Assignment by Qualified Professionals ................... 6 3.0 PROJECT INFORMATION ........................................................................................ 7 3.1 Proponent Information and Contact ............................................................... 7 3.2 Project Name, Location and History ............................................................... 8 3.3 Land Tenure Information ................................................................................ 9 4.0 KNOWLEDGE BASE: