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TAILINGS MANAGEMENT

At end-2020, our 11 operations – including our three JV sites, being Asanko in Ghana, Gruyere in Australia and FSE in the Philippines – contained 37 TSFs, of which 12 were active and one under construction. Of the 12 active TSFs, we have two in-pit TSFs (Agnew and St Ives), six downstream/centre-line TSFs, and four upstream TSFs.

Our mines in Australia and South Africa are located in relatively dry regions, and limited amounts of supernatant water are stored in the facilities. This significantly improves their overall performance and integrity. In Ghana, the Tarkwa and Damang TSFs are designed in line with industry best practices. We have implemented critical controls and performance objectives to ensure that the TSF embankments remain stable throughout both the wet and dry seasons and over the life of the facilities. Our technical teams continue to work with Galiano Gold, which manages Asanko, to maintain the good operational performance of the lined and downstream-raised TSF.

The Lepanto TSF located in the Philippines is well managed, with no visible signs of instability and adequate freeboard. No safety incidents associated with the project have occurred to date. The TSF is located in a region prone to high seismic activity and frequent typhoons. As a result, Gold Fields and Lepanto Mining commissioned external consultants to develop a more reliable risk profile of the Lepanto TSF, along with potential risk control measures that could further improve the facility's risk profile. We expect an independent summary from the consultant in Q1 2021.

Solar farm and wind turbines, Agnew, Australia

Total tailings depositions increased by 20% in 2020 from 2019, totalling 59Mt. This increase is mostly due to our Gruyere mine producing for a full year for the first time.

A detailed profile of Gold Fields' TSFs can be found on our website at www.goldfields.com/environment-tsf.php

GISTM

The global mining industry's TSFs are in the spotlight following several tailings dam failures over the past few years – particularly the catastrophic tailings collapse at Vale's Feij√£o iron ore mine in Brumadinho, Brazil, in January 2019, which resulted in the deaths of 270 people.

After the Brumadinho tragedy, ICMM members, along with the UN Environment Programme and UN Principles for Responsible Investment, convened an independent panel of experts to develop a new international standard for TSFs. Accordingly, the GISTM was launched on 5 August 2020, thereby establishing a widely accepted global standard on tailings management that can be applied to both existing and future TSFs. The GISTM covers the entire tailings facility lifecycle – from project conception to post-closure – and strengthens current mining industry practices by integrating social, environmental, local economic and technical considerations.

All ICMM members, including Gold Fields, have committed to ensure that all TSFs with "extreme" or "very high" consequence category ratings comply with the GISTM by 5 August 2023. All other tailings facilities that are not in a state of safe closure will conform to the GISTM by 5 August 2025. Soon after the launch in August 2020, we commenced a detailed, site-specific analysis of each TSF against the GISTM to identify gaps and confirm our compliance roadmap. We expect to complete this work by mid-2021 and will then start towards closing any identified gaps.

TSF governance and technical Oversight

As required by the GISTM, Gold Fields' Board approved a new TSF Management Policy Statement in 2020. We believe this policy statement demonstrates our commitment to:

  • Safe and responsible management of tailings with the aim of zero fatalities and catastrophic failures
  • Allocate appropriate resources to support tailings management activities
  • Implement effective governance over tailings management
  • Cultivate an organisational culture that promotes learning, communication and early recognition of problems relating to TSFs
  • Emergency preparedness and post-incident recovery should a failure occur
  • Implement a tailings safety review process, including independent reviews

All Gold Fields' active TSFs are subject to a comprehensive third-party review every three years, covering operational and legal aspects, as well as sustainable development. These reviews are also used to ensure ongoing compliance of our operations with our Group TSF Management Guideline and applicable design guidelines. As required, facilities that have an "extreme" consequence rating are subject to annual third-party operational reviews.

We retain an Engineer of Record (EoR) for all of our active sites. The role of EoR is filled by a suitably qualified external engineer, who is supported by the consulting engineering company they work for. EoRs are responsible for reviewing and approving all engineering and design data, associated operating and monitoring procedures, as-built drawings and facility inspections to confirm physical integrity, safety, and ancillary structures' performance.

The most recent round of independent external audits commenced at the end of 2019 and was completed by mid-2020. These reviews, the most comprehensive external audit of our TSFs, concluded that the operations and management of all TSFs are in line with recognised industry tailings management and safety practices.

Gold Fields' Board continued to strengthen its oversight of the Group's TSFs by introducing quarterly TSF management reports, progressive implementation of real-time environmental and geotechnical monitoring, and increased external and independent verification. We also embarked on a programme to further improve the operational safety of our TSFs including, where practical, consideration of filtered and dry-stacked tailings, improved water management and in-pit tailings disposal. These initiatives are also the subject of work at the ICMM to improve critical TSF controls and reduce tailings water content.

Gold Fields has been progressively implementing several technical improvements to its TSFs and is increasingly using tools linked to cloud-based dashboard systems that enable real-time monitoring and analysis of responses and measurements.

Waste management

Process plant tailings waste and waste rock are two of the most significant by-products produced by mines. By responsibly managing these waste streams, we can minimise their impact on the environment and our host communities.

In terms of general waste, we have an internal target to limit waste generated for disposal at landfill sites to 2015 levels, which totalled 11.2kt. In 2020, we generated 9.5kt in non-hazardous waste and 1.7kt in hazardous waste – 11.2kt in total, thereby meeting our target. During 2020, Gold Fields recycled 60% of all non-mineralised waste generated in 2020, compared with 50% in 2019. Waste such as plastic, scrap metal, oils and hydrocarbons are recycled off-site by specialist recyclers.

GROUP MINING WASTE

1 The increase in tailings from 2019 is due to Gruyere operating for the full year for the first time
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