Tailings

We are committed to aligning with the Global Industry Standard on Tailings Management over a multi-year journey. Our Assets are currently developing plans reflective of local requirements, regulations, and our internal governance system.  

We currently own and operate four active tailings facilities at Prominent Hill and Carrapateena in South Australia, and the Antas mine in the Carajás East Hub in Brazil. We currently do not have any closed tailings facilities.

Governance

Our Tailings Global Performance Standard guides our approach to managing mineral waste within our tailings storage facilities. The Standard ensures our tailing facilities are designed, constructed, and managed to enable safe impoundment of mine tailings and residues, and to prevent uncontrolled releases and seepage to groundwater.  

The Global Performance Standards describe the minimum requirements of Assets and Corporate Functions to carry out activities in a financially, environmentally, and socially responsible way. The Standards apply to our workforce and anyone undertaking work on our behalf. 

All Global Process and Performance Standards are subject to the Assurance Process Standard, where compliance against the Standard and opportunities for improvement are monitored by the Corporate Assurance Function in addition to the self-assurance activities undertaken by the Assets and corporate functions themselves.   

Management of our tailings facilities

Our tailing storage facilities in Australia are designed, constructed, and operated in accordance with Australian National Committee on Large Dams (ANCOLD) requirements and International Committee on Large Dams (ICOLD) bulletins. In Brazil, our facility is designed and operated in accordance with the guidelines of Law No. 12334/2010 National Dam Safety Policy and Resolution No. 95/2022.  

All our tailings facilities are managed, monitored, and inspected by experienced operational and processing personnel. Relevant personnel undertake daily inspections, and the Responsible Tailings Facility Engineer undertake weekly to fortnightly inspections. Each facility has a designated Engineer of Record who is responsible for inspections, reviewing dam safety monitoring data and operations, maintenance, and monitoring requirements, and alignment with relevant guidelines and standards. Independent annual or biannual third-party audits are undertaken at our Australian Assets, while in Brazil the Secretary of State for Environment and Sustainability (SEMAS) undertakes audits on a six-monthly basis and the National Mining Agency (ANM) annually.  

2022 activities

All Assets with active tailings facilities completed reviews against the Global Industry Standard on Tailings Management to identify any gaps and identify pathways to alignment.  

During 2022 Carrapateena completed stage two of its tailings storage facility, consisting of a 14 metre downstream raise using approximately 1.6 million m3 of compacted mine rockfill. Stage two is expected to provide adequate tailings storage capacity until 2028. At Prominent Hill, the Tailings Operational Management Plan was reviewed and updated, and the stage six uplift design completed ahead of activity planned for 2024/25. Geotechnical and geochemical investigations at both Carrapateena and Prominent Hill have confirmed tailings to be non-acid forming.  

In Brazil, activities focused on decommissioning the Antas Norte facility and disposing tailings in the depleted mine pit. As a result, no continuous operational activities were undertaken.