IGO SUSTAINABILITY REPORT 2020

MINE CLOSURE We recognise that we have a responsibility to close mines in a way that leaves a positive, healthy and sustainable legacy. Planning for mine closure must consider social, economic, physical and biological parameters that can change over time, particularly when the planning horizon extends past a decade. Taking the lead on closure and rehabilitation planning can significantly reduce the complexity and cost of closure in the long run. IGO’s planning and cost provisioning for mine closures starts during exploration and project development and extends across the operation’s life cycle. In accordance with our Common Management System Standard 15 — Acquisition, Divestment and Closure, we develop and maintain a closure plan for each project to ensure we are prepared and understand the cost of closure. The closure plan also outlines the process for developing and obtaining agreement on completion criteria that will demonstrate successful post-closure outcomes. Both the Nova and Tropicana operations have approved mine closure plans, developed in accordance with Western Australian regulation. Mine Closure Plans (MCP) are live documents that are continually updated throughout the life of the operation. We continue to investigate and refine closure strategies at all our operations in accordance with our Group Environmental Standard 1 — Mine Rehabilitation & Closure and the Group Finance Standard 1 — Provisions for Mine Closure. The revision of these plans follows a structured approach, incorporating both external regulatory requirements as well as meeting internal standards to ensure adequate stakeholder engagement throughout the planning process. Mine Plan – Define Domains Mine Closure Plan Closure Cost Liability Report Internal and External Closure Cost Analysis Demolition and Earthwork Scope Final Landforms Engineered Designs Completion Criteria (Basis of Design) Development REGULAR ENGAGEMENT ESTIMATED COST OF CLOSURE FACILITY FY20 FY19 Nova Operation $38,230,579 $37,832,616 Tropicana Operation 1 $28,368,196 $24,608,361 Total 2 $66,598,775 $62,440,977 1. This figure represents IGO’s 30 per cent share in the Tropicana Operation. 2. The total cost of closure includes the present value of the estimate cost of rehabilitating and restoring the environmental disturbance that has occurred because of our operations. Finally, revised MCPs enable provisions for the estimated cost of rehabilitation, decommissioning and restoration relating to areas disturbed by our operations throughout the year. These are reviewed, and if required, updated annually. The Nova Operation has a current mine life to 2026, after its reserves were updated in FY20. IGO submitted an updated mine closure plan to the Western Australian Department of Mines, Industry Regulation and Safety in December 2018, following approval for the construction of a permanent waste rock dump at the site. The Tropicana Operation has a current estimated mine life of seven years, based on Ore Reserves and Mineral Resources as at 31 December 2019. At the end of FY20, the estimated total cost of rehabilitating and restoring the environmental disturbance that has occurred as a result of our operations amounted to $66.6M. Identifying the gaps In FY20, IGO completed a gap analysis of the existing MCP at our Nova Operation, to understand the current knowledge gaps and establish a future workplan. This gap analysis identified and established 15 future workplans that will improve our understanding of current closure knowledge and address the gaps. The project was collaborative and ensured engagement with all key subject matter experts across the business. During the financial year, we also completed erodibility testing and modelling of the TSF and waste rock dump at the Nova Operation, to better understand landform stability and inform closure planning. The overall objective of the study was to develop two-dimensional rehabilitation profile shapes that are erosionally stable in the long term. This project has helped define key operational, rehabilitation and closure planning objectives, including: • rehabilitation batter shape for both the waste rock dump and TSF; • maximum storage capacity of the waste rock dump; • mine closure capping configurations for both the waste rock dump and TSF; and • the required volume of materials to deliver the mine closure cover system. It has also informed and helped determine: • field trials to test capping and landform batter designs; • PAF (potentially acid forming) material management and rehabilitation parameters; and • if the existing embankments sheeted with TSF footprint and borrow pit materials are likely stable in the short and long term. Mine closuring planning is an ongoing process, and we will continue our work to inform knowledge gaps to ensure we achieve closure objectives. Engagement and collaboration We work with industry and other international organisations on sharing best practice for mine closures. IGO was a key contributor to the Western Australian Biodiversity Science Institute's Framework for Developing Mine-site Completion Criteria in Western Australia. This project was carried out to support the prioritisation of data collection and monitoring activity to enable the development and assessment of completion criteria. It reinforces the importance of engagement and collaboration within the industry to inform best-practice mine closure planning. Engagement with stakeholders both internal and external to IGO is a critical part of the planning process. The potential impacts of closure are an ongoing consideration in our engagement with governments and local communities, including how closure can affect our support of community development initiatives and local business. In recognition of the potential impacts of mine closure to the environment, community and the economy, we have increased our effort in the closure planning process. Mine rehabilitation fund IGO, like many other mining companies, pays a levy to the Western Australian Government’s Mining Rehabilitation Fund for the purpose of funding the closure of abandoned mine sites i.e., sites where liability rests with the government because of business failure or other historic reasons. In FY20, IGO’s levy payments totalled $0.11 million. Closure planning is an essential process that occurs at all stages of a mine’s life cycle. The end of a mine’s operational life is far from being the end of its social and environmental impact. Nova Operation facilities 62 — IGO SUSTAINABILITY REPORT 2020 IGO SUSTAINABILITY REPORT 2020— 63 RESPONSIBLE OPERATIONS