While government is stating that acid mine drainage (AMD) in South Africa is not an insurmountable problem and that the country will certainly win the struggle, industry experts and activists are concerned that the true extent of the challenge has not yet been acknowledged.

The Department of Water Affairs (DWA) had AMD treatment pumps installed at the Central basin facility last month, as part of its R2.2-billion short-term solution to deal with AMD on the Witwatersrand.

This solution was the second to be imple- mented to treat AMD in the near term, the first being the Western basin’s immediate solution, commissioned in April 2012.

Speaking at the ceremony last month to celebrate the lowering of the Central basin pumps, Water Affairs Minister Edna Molewa said: “This process will ensure that AMD will not reach the environmentally critical level (ECL), which is prescribed by our legislation, and will also guarantee the safety of the environment and the people.”

The third and final short-term solution will be implemented in the Eastern basin once the contract is awarded later this month.

However, Water Stewardship Council trustee Dr Anthony Turton tells Mining Weekly that the Eastern basin solution will not be implemented in time to avoid the AMD breaching the ECL, as no funds have been allocated to this project by the DWA or the National Treasury to date.

“The ECL will be breached between the first and third quarters of 2015 and, with the lead time for construction being 18 months, we will thus clearly not make it in the Eastern basin because we have been distracted,” he says.

Federation for a Sustainable Environment leader Mariette Liefferink shares Turton’s view and notes: “Nothing has happened in the Eastern basin yet, where the largest amount of water will have to be neutralised and desalinated. We are now in the scoping phase of [this basin’s] treatment works.”

However, she states that it is a positive that government is finally acknowledging that AMD is a serious threat.

“For many years, government has denied the existence of AMD. They suppressed evidence and there were no proactive management plans in place, so the paradigm shift in that regard is heartening – at least, it is regarded as an emergency now,” Liefferink says.

She adds that while government is to be commended for this acknowledgement, there still are no proactive management plans in place to address a possible AMD decant in the far Western basin of the Witwatersrand, the Free State goldfields and the (Klerksdorp, Orkney, Stilfontein and Hartebeesfontein basins, in the North West.

“I do believe that, while government has acknowledged the problem, the implementation [of solutions] is still problematic,” Liefferink says.

Meanwhile, Turton says that government has not yet grasped the complexity of the AMD issue.

“This is reflected in the linear thinking we see in the roll-out of the current solution, which is focused only on treating the AMD by abstracting and neutralising it, without any significant understanding of the ‘bigger picture’ in which it is embedded.”

He adds that the common belief is that AMD comes from the mine voids, resulting in large sums of money being spent on neutralising the water at the point of decant.

However, Turton says that his work is increasingly showing that there are many discreet pathways followed by AMD, each nested in a bigger whole.

“The main AMD is . . . created when acid rain falls on flat-topped tailings dams, triggering the initial acidification process that, in turn, leaches uranium concentrated in the crust. This is later mobilised by either wind or water, entering various flow pathways that we have not yet debated at government level.”

He tells Mining Weekly that this linear thinking could result in much money being wasted on the wrong solution without addressing the bigger picture, which includes uranium con- tamination from main dumps.

“The other bigger issue is the Zama Zama mineworkers, who create a plethora of problems, including undermining the surface of the reef-bearing land, with implications for residential houses built on that land. There is not a policy in place to address these issues,” Turton states.

Liefferink also states that it is a concern that the diffuse sources of AMD in the Witwatersrand area are not being addressed.

“These [diffuse sources] include 270 mine dumps, which contain six-billion tons of iron pyrite tailings. This is important because pyrite is the catalyst for AMD.

“As these mine dumps cannot be maintained in an oxygen-free environment, every time it rains, the dumps will produce acid mine water because the rainwater oxygen will combine with the pyrite and produce acid mine water. It will continue for hundreds of years and nothing is being done about this at present,” she says.

WESTERN BASIN
Meanwhile, despite the short-term solution having been implemented in the Western basin, recent heavy rainfall has led to the AMD in this basin once again starting to decant.

Liefferink points out that, as of the end of March 2014, 30-million litres a day of untreated AMD was flowing into the river systems from the Western basin.

At the Central basin pump-lowering cere- mony, DWA deputy director-general Trevor Balzer described the heavy rainfall earlier this year as an “act of God”, adding that “we need to accept that we put our . . . solution in the Western basin, but God decided to play tricks on us to try to find a way to test our ability to manage the environment”.

Also speaking at the ceremony, DWA water-quality management senior manager Marius Keet said that, in trying to handle the situation, the Trans-Caledon Tunnel Authority had bought two new pumps, soon to be installed at the Western basin.

“We are also investigating other opportuni- ties, such as using existing facilities in the area, but we are also considering building new clarifiers,” he said, adding that the Western basin plant would probably be refurbished further by adding clarifiers, but added that this would be at a financial cost that was yet to be considered.

Meanwhile, Turton says the recent decant in the Western basin is evidence of the lack of understanding of the bigger picture and the role of AMD.

“The Western basin stopped decanting in about 2011, when we drew the void level down by about 5 m. In the first three months of 2014, heavy rainfall occurred in that area, resulting in massive decanting again. Clearly, we have failed, because the taxpayers’ money we spent has not been used to [make] a viable impact,” he says.

Turton adds that the current decant opened a window of opportunity for the country to revisit its core thinking on the AMD solution.

“I believe the solution is on a new form of engagement between the State and the mining industry because that includes mining as part of a viable solution, whereas, at present, it is . . . seen to be part of the problem,” Turton says.

LONG-TERM SOLUTION
Molewa said last month that government’s long-term AMD solution, which would entail the neutralisation and desalination of mine water and, therefore, making it more environmentally friendly than the short-term solution, would be in place by 2015/16.

However, Liefferink tells Mining Weekly that this is unlikely to be the case. “I don’t think they will meet the implementation date of 2015/16.”

She explains that, according to the long-term solution’s feasibility study, R6.5-billion is needed for the solution’s infrastructure, with an additional R750-million and R250-million a year needed to cover operational costs and maintenance respectively.

“I have no knowledge of any provision made by the National Treasury for the funding of the long-term treatment. I have no knowledge that there has been an invitation to tender or that tenders have been awarded for any for the long-term treatment. I am also not aware that an implementing agent has been appointed,” she adds.

Liefferink further points out that the implementation of the long-term solution is a matter of reasonable urgency because, in terms of the DWA’s remediation strategies for the Vaal river system, if the AMD is not neutralised and desalinated by 2014/15/16 – depending on the rainfall – the Vaal river will lose its dilution capacity.

Meanwhile, Turton says that government’s long-term strategy, which will probably be based on desalination, will create two new problems – high-energy costs over the full lifetime of the process and the need to build massive storage facilities for the high-density sludge.

“The cost of the storage facilities alone runs into hundreds of millions of rands and their very presence will create a new hazard in perpetuity . . . this flawed assumption needs to be revisited. There are alternatives that should be considered. I call for a robust public debate on the business models that underpin any solution because the taxpayer will be asked to foot the bill in perpetuity, so they need to be comfortable that the best solutions have been selected,” Turton says.

OTHER MINING AREAS
Molewa also said at the ceremony last month that government acknowledged that AMD was not unique to the Witwatersrand and that the problem also existed in other provinces, such as Mpumalanga and KwaZulu-Natal.

“We haven’t sat back. We are working around the clock to ensure that, in those provinces, we act proactively,” she said, adding that these provinces had the advantage of the mines still being operational and, therefore, government was working with mining houses in the area to ensure that there would be no AMD decant in future.

Mineral Resources Minister Susan Shabangu, who also attended the lowering of the Central basin pumps ceremony, added that mining licences were not granted to companies if financial provision was not made for environmental rehabilitation.

However, Liefferink states that while mining companies do make provision for the treatment of AMD, this financial provision is made for, perhaps, only 20 years, while the water treatment would have to continue for hundreds of years, ultimately continuing to be a burden on the taxpayer.

Molewa, however, while acknowledging the extent of the challenge, is confident that South Africa will win the struggle.

“AMD is not a problem that we are unable to deal with. We are on it and we are proving that we will certainly win. We are equal to the problem,” she said.