Long-term environmental obligations are based on Barberton Mines, Evander Mines and Phoenix Platinum environmental plans, in compliance with current environmental and regulatory requirements. The provision is based on the net present value of the estimated cost of restoring the environmental disturbance that has occurred up to the Statement of Financial Position date.

Increases due to additional environmental disturbances are capitalised and amortised over the remaining lives of the mines. The estimated cost of rehabilitation is reviewed annually and adjusted as appropriate for changes in legislation or technology. Cost estimates are not reduced by the potential proceeds from the sale of assets or from plant clean up at closure.