12.	ENVIRONMENTAL REHABILITATION EXPENDITURE
	The estimated cost of final rehabilitation, comprising the liability for decommissioning of assets and restoration, is based on current legal requirements and existing technology and is reassessed annually and disclosed as follows:
12.1	Decommissioning costs
	The present value of estimated future decommissioning obligations at the end of the operating life of a mine is included in long-term provisions. The related decommissioning asset is recognised in property, plant and equipment when the decommissioning provision gives access to future economic benefits. The unwinding of the obligation is included in the income statement as finance costs. The estimated cost of decommissioning obligations is reviewed annually and adjusted for legal, technological and environmental circumstances that affect the present value of the obligation for decommissioning. The related decommissioning asset is amortised using the lesser of the related asset’s estimated useful life or units-of-production method based on estimated Proven and Probable Ore Reserves.
12.2	Restoration costs
	The estimated cost of restoration at the end of the operating life of a mine is included in long-term provisions and is charged to the income statement based on the units of production mined during the current year, as a proportion of the estimated total units which will be produced over the life of the mine. Cost estimates are not reduced by the potential proceeds from the sale of assets.
12.3	Ongoing rehabilitation costs
	Expenditure on ongoing rehabilitation is charged to the income statement as incurred. Any subsequent changes to assumptions in estimating an obligation are added or deducted from the asset to which it relates. Reductions over and above the remaining carrying value of the asset are recognised in the income statement.