Planning for mine closure
Mining is a temporary activity. However, we have a long-term view of the land under our management, recognising that adverse impacts must be remediated to demonstrate responsible stewardship of natural resources. All our project life cycles focus on the eventual restoration of the land we use.
Planning for mine closure is an essential part of mining responsibly and, in most cases, is required by law. We follow best practice when planning mine closure programmes. This forms part of our responsibility to our host countries and our PACs. Our operations have integrated rehabilitation plans to ensure we meet our closure objectives as efficiently as possible. With these plans, we can better manage our operations' environmental impact and identify cost-effective rehabilitation strategies. Plans are revisited annually. In 2020 the Group rehabilitation provision amounted to US$16.1 million.
Remediating and revegetation the Letšeng mine poses a unique challenge due to its high altitude of ±3 200 metres above sea level.
A series of trials to examine different rehabilitation applications to test the closure criteria began in 2012 and form the basis for estimating the mine's rehabilitation and closure costs. These trials were selected to replicate the rehabilitation of the mine's main waste residue disposal facilities: fine tailings (slimes), coarse tailings and waste rock. The trials utilised waste rock and tailing reserves, allowing for minimal topsoil requirements. The trials also included studies on vegetation rehabilitation and restoration of natural ecosystems. Vegetation restoration studies were conducted in the mining lease area to research veld rehabilitation options.
To achieve our rehabilitation goals, various initiatives were undertaken, including nursery and rehabilitation trials and concurrent rehabilitation projects. Academic studies, in collaboration with the National University of Lesotho (NUL) and the North West University (NWU) in South Africa, were conducted at Letšeng to inform rehabilitation and present mining strategies and techniques.
Our Ghaghoo mine remains under care and maintenance; its rehabilitation plans continue to be reviewed as we investigate restorative initiatives to reduce the end of life of mine liability.
The Group engaged with independent experts at both Letšeng and Ghaghoo to understand the quantum of work to ensure safe and responsible mine closure at the end of mine life. The Group's rehabilitation plans and resultant liability undergo annual external reviews.