/ 24 June 2011

No quick fix for acid mine drainage

No Quick Fix For Acid Mine Drainage

South Africa is a long way from finding a long-term and financially sustainable solution to the problem of acid mine drainage, and environmental groups are critical of the government’s failure to conduct adequate research into the impact of the toxic water on people and animals.

This emerged during public hearings staged by Parliament’s water and environmental affairs committee this week.

The hearings were a sequel to a report earlier this year by a team of experts appointed by the interministerial committee on acid mine drainage. The task team recommended a number of measures to address the issue, including:

  • Pumping out underground mine water to prevent it reaching the environmentally critical level;
  • Controlling the ingress of water into mine shafts; and
  • In the short term, treating acid water by neutralising the high acidity and high metal content, followed in the longer term by the desalination of the water before pumping it into the river systems.

In response to the millions of litres of acid mine drainage already flooding or threatening to flood South Africa’s streams, rivers, cities, and towns, a variety of solutions have been proposed with varying degrees of effectiveness and cost.

But the experts warned that their recommendations were only designed to avert an impending crisis and stabilise conditions. The long-term management of acid mine water and its impact would have to continue for many years, they said.

Marius Keet of the department of water affairs told the committee that three priority areas that required immediate action had been identified — all in the Witwatersrand.

They were the western basin in the Krugersdorp region where acid mine water was already spilling into the Tweelopies Spruit; the central basin with Johannesburg at its heart where acid water levels would reach a critical level within a year; and the eastern basin where the pumping of mine water had ceased following the halting of operations at the Grootvlei mine.

Mariette Liefferink, a director of the Federation for a Sustainable Environment (FSE), told the Mail & Guardian that the full cost to end-users was not fully understood. About 11 500 people depended for their drinking, agricultural water and water for livestock on the Tweelopies Spruit system, and acid mine water had been coming to the surface in the western basin since 2002 at a current rate of 20-million litres a day.

She said that no epidemiological or toxicological studies had been conducted to determine the impact of this water on the people or animals that used it. “I don’t think anyone wants to know [the answer].”

In a written submission to the committee, the FSE was critical of the experts’ report, particularly its recommendation for the neutralisation of acid mine water in the short term.

It said that the impact of neutralisation, which resulted in high sulphate loads and heavy-metal sludge residue in the water, had not been properly considered.

“The costs and impacts will be unfairly and inequitably borne by agricultural users, surrounding industries, domestic or potable users and the aquatic ecosystems and environment,” the FSE said, and referred to the damage that an attempt at neutralisation had had on the Krugersdorp Game Reserve.

It said that water from the Tweelopies, neutralised by lime, had formed a sludge in two receptor dams in the reserve, the Hippo Dam and Aviary Dam. Two hippos had been coated with a heavy-metal residue in the Hippo Dam, and a heavy metal crust had formed on the bottom of Tweelopies.

The release of neutralised water meant that good-quality water would have to be taken from the Vaal Dam to dilute the high salt loads caused by neutralisation, and that would affect the security of water supply.

The FSE’s report also said that there was a critical need for an audit of the financial provisions and the extent of the environmental liabilities of mines operating on the East Rand, Central Rand and West Rand goldfields.

Liefferink argued that the process did not allow for public participation, sidelining those affected by acid mine water from decision-making.

As part of government’s bid to address the crisis, the Trans-Caledonian Tunnel Authority was appointed in April to install the pumping and treatment infrastructure needed to deal with the underground mine water, and to put infrastructure in place to convey treated water to nearby watercourses.

Johan Claasens, of the tunnel authority, warned that the project would only address the three immediate priority areas, and that about R750-million was needed to address the overall problem, much more than the R225-million currently allocated to the department of water affairs.

He said the finalisation of a due diligence review, which was being conducted by the tunnel authority and was expected to be released in early July, would provide a better understanding of the infrastructure needs and cost implications.

Maselaganye Matji, from the treasury, told the committee that a long-term solution was needed that did not require ordinary taxpayers to pay for the “sins of business” in perpetuity.

Urgent solutions were required, including the possibility of an environmental or acid mine drainage levy on the mines that could be used to fund the treatment of acid water, said Matji.

The problem was also likely to require the exploration of public-private partnerships to treat acid mine water, which could be sold back to businesses or industry. This would make it possible to treat the problem in a way that would become financially self-sustaining.

The authorities have been hesitant to lay the blame at any one mining company’s door. They argue that this is because the scale of the problem goes back a century, when legal frameworks for the treatment of acid water and the remediation of environmental degradation did not exist.