In terms of the method of tailings storage, 39 used wet deposition, while 52 used either dry-stacked or in-pit deposition.
LISTED mining companies, including Kumba Iron Ore, at the weekend responded to mounting pressure from the Church of England, which has raised safety concerns following the Brumadinho dam failure in Brazil that claimed 300 lives in January.
BHP Billiton, Glencore, Gold Fields, Anglo American plc, Anglo American Platinum and Kumba Iron Ore are some of the companies that provided details of their tailings dams on their websites following a push-back from the church.
In April, the Church of England Pensions Board and Swedish Council on Ethics for AP Funds, supported by 96 investors which manage R153.72 trillion in assets, wrote letters to 683 listed resource firms requesting they disclose their tailings dams.
Anglo American plc said it managed 91 tailings facilities, 40 of which were in active use, 33 were inactive or in care and maintenance, and 18 were closed or rehabilitated.
The company said, in terms of the method of tailings storage, 39 used wet deposition, while 52 used either dry-stacked or in-pit deposition.
Anglo American plc chief executive Mark Cutifani said the company was working on a number of technologies that it expected to significantly reduce the volume of waste material it produced.
“A number of these technologies also offer major energy and fresh-water usage reductions for every ounce or ton of metal or mineral we produce,” Cutifani said.
Anglo American had updated its technical standard for facilities (TSF) safety management in early 2014 to global standard to mitigate risks.
“Anglo American has also received assurances from the operators of non-managed joint ventures in which Anglo American has an interest relating to the safety of TSFs at those operations,” Cutifani said.
Anglo American’s subsidiary, Anglo American Platinum, said it managed six active tailings treatment facilities, five of which are in Limpopo and one in Zimbabwe.
Kumba Iron Ore said it managed four tailings dams at its Sishen and Kolomela mines in the Northern Cape. It also said the facilities were above board.
Gold Fields, the owner of South Deep in Gauteng, said it managed 32 tailings facilities, of which 12 were active and one would be commissioned imminently.
“All Gold Fields’ tailings storage facilities, as well as associated pipeline and pumping infrastructure, are subject to an independent, external audit every three years – or more frequently where required by local circumstances or regulations – as well as regular internal inspections, monitoring and formal annual Engineer of Record reviews,” Gold Fields said.
Investors were concerned that there was no global register of tailings facilities and the precise scale of the risks were not clear, nor was it clear which company has responsibility for which facilities.
It has been estimated that there are 18 000 tailings facilities worldwide, of which 3 500 are active.