A controversial report that downplayed the risk of acid mine water flooding in Johannesburg’s central business district was a red herring aimed at boosting business confidence, critics say.
The report made headlines when it was released last week because it denied fears that the basements of high-rise buildings in the CBD could be flooded by the middle of next year.
It said “sensationalised coverage of acid mine drainage-related problems in Johannesburg not only by national but also international news media” had damaged “business confidence and corporate image”.
Commissioned by Absa and Standard Bank, which both have buildings in the CBD, the report by Professor Frank Winde and his team at the Mine Water Research Group of North-West University was this week described by critics as a move to soothe the banks’ shareholders’ concerns.
“It is a desktop study, not an environmental impact assessment, augmented by primary data supplied by the mining industry,” said Mariette Liefferink, the chief executive of the Federation for a Sustainable Environment.
It was produced by respected academics, she said, but, by underplaying the risk of flooding, they were causing confusion and possible apathy about dealing with the problem.
“The result will be what happened on the western basin of the Reef. Warnings of acid mine flooding were ridiculed for years until it finally took place and we have seen how devastating the impact is.”
The main findings of the report differed from earlier research by a multiÂdisciplinary team of experts. On the basis of their report, an inter-ministerial committee persuaded the Cabinet to allocate R400-million to mitigate the impact of acid mine drainage on the Reef.
Focusing on the central basin, the Winde report predicted a slower rise of the underground mine-water table, a significantly lower volume of decant and a much less severe impact of untreated decant water on the quality of receiving streams.
It found no evidence that rising mine water posed a flooding risk to buildings in central Johannesburg.
“Using the pile levels of the Absa Tower East as the deepest of the bank buildings considered in the Johannesburg CBD, it was calculated that the maximum elevation to which the mine water table can rise in the central basin mine void is 90m below the base of these piles.
“For the new admin building of Standard Bank, which according to the latest issue of You magazine is already being flooded, the safety margin is 106m,” it said.
It recommended “a more sustainable, low-cost, low-energy solution” to the problem, “as opposed to the currently proposed high-cost, high-energy, pump-and-treatment option likely to be subsidised ad infinitum by society”.
One of the authors of the original report, Henk Coetzee, a Council of Geosciences environmental scientist, said this week the experts who drafted the first report could not comment because they could not get hold of a copy of the new research.
“We have seen a summary, but only the banks have the full report. Even the department of water affairs’ experts have not seen it,” Coetzee said.
Winde, a member of the School of Environmental Sciences at North-West University’s Potchefstroom campus, said his clients — the banks — were willing to make the full report available to the government but did not want to be drawn into a debate.
“We are not trying to make light of a serious problem,” he said.
“We differ from the original report only in the amount of risk involved and some of the numbers.”
His report had shed new light on the dangers of radioactive radon gas caused by acid mine water rising in underground aquifers, he said. Radon was a leading cause of lung cancer in uranium miners.
“The risk needs to be assessed, especially for informal settlements. The gas, formed through the radioactive decay of uranium contained in the mine water, can easily accumulate in low-lying, poorly ventilated shacks, which often lack concrete floors that could limit a radon influx.”
A number of other flood-related risks not considered previously had been identified, Winde said. These included the possible subsidence of infrastructure in low-lying areas, such as the M2 highway.
“Ours was a once-off study that put these things into perspective,” Winde said. “Now no one can claim they didn’t know better.”