Hope springs (not) eternal in spat over toxic sludge Featured

Written by  Zwanga Mukhuthu Tuesday, 24 June 2014 11:36
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by Zwanga Mukhuthu of M&G

Fears that a facility to treat acid mine drainage could contaminate plants, animals and people. Government is forging ahead with a R1-billion project for the treatment of acid mine drainage in Ekurhuleni – despite a fierce backlash by residents and environmental experts over the millions of cubic metres of toxic, and possibly radioactive, sludge the project will churn out.

 

More than 1 000 residents have signed a petition against the siting of the treatment plant at the Grootvlei mine’s number three shaft, about 5km from the centre of Springs, which forms part of the Ekurhuleni Metropolitan Municipality on Johannesburg’s East Rand.
A spokesperson for the residents warned that the plant could render the area uninhabitable and described the government as “mad” for locating it there.
At the same time, a prominent environmentalist has pointed to the dangers of seepage into a residential and farming area with an already fragile ecosystem.
Water affairs department spokesperson Sputnik Ratau conceded there had been “public resistance” during the environmental impact assessment process. But he also said ¬construction and pumping would go ahead despite the backlash, after the environmental affairs minister granted authorisation under ¬environmental law for emergency works.
The contract was awarded last month to the CMC/PG Mavundla Engineering Eastern Basin joint venture for a price of R956-million.

Short term measure

The scheme is a short-term stabilisation measure to head off the worsening acid mine drainage (AMD) crisis in the eastern basin of the Witwatersrand, a 768km2 “mine residue area” that includes agricultural land and highly populated centres such as Benoni, Brakpan, Springs and Nigel.
It will comprise a neutralising plant for the AMD, a pump station, underground pipelines and a 14m-high facility to store 1.75-million cubic metres of high-density sludge, to be extracted over a maximum of eight years. Construction will take about 18 months.
Because it is hygroscopic – that is, it draws water from the atmosphere – the toxic sludge will remain in a permanently jellified form.
Once treated, the water will go back into the Blesbokspruit, part of the Vaal Barrage system, a national water resource. This has provoked major worries among downstream users, including South Africa’s largest beef-farming operation, Karan Beef near Heidelberg (see “Livelihoods under threat”).
AMD is the result of water flooding subterranean voids left by gold mining at disused mines where pumping has stopped, and becoming acidified by contact with pyrites. Apart from the risk of ground water being contaminated, the water can “decant” – break the surface – and pollute surface water bodies.

Threatened ecosystems

Decanting has already occurred in the western basin of the Witwatersrand around Krugersdorp.
Mariette Liefferink, chief executive of the Federation for a Sustainable Environment, said Springs residents have every reason to be concerned, as the high-density sludge to be extracted and stored will contain toxic and potentially radioactive metals including uranium, aluminium, lead, cadmium, manganese, iron, copper, cobalt and zinc.
Liefferink said that, according to her preliminary assessment, none of the nine sites earmarked for the disposal of metal sludge are suitable.
In a letter to Digby Wells Environmental – the company assessing the environmental impact for a longer-term AMD solution – she warned that the sites are close to the Blesbokspruit, whose ¬“ecological status is already poor … additional stress on the system will be unacceptable”.
Liefferink said if the sludge is disposed of in an unlined facility or close to wetlands it could result in the seepage or movement of toxic material into ground water, soil, wetlands and surface water bodies. Without stringent controls, she believes it is almost certain that crop soils will be irrigated with contaminated surface or underground water.
She also warned of the risk to ¬“ecosystem goods and services” on disturbed, fragmented or polluted properties, and of the potentially toxic impact that pollutants that have built up in animals and plants could have on human beings.
The treatment scheme could further reduce species diversity and irreversibly alter the ecosystem, Liefferink said, adding that the well-known Marievale Bird Sanctuary is also at risk.

Delays

In response, Ratau said the government had to address the AMD crisis, which it had inherited when it came to power in 1994.
Meanwhile, the water affairs department has come under fire for the two-year delay in awarding the construction tender, amid fears that AMD in the eastern basin will soon rise to the surface.
Ratau revealed that the department’s original intention was to hand out the contract in the last quarter of 2012, but that, “while awaiting approval of funding and the cost-recovery mechanism, the contract award was deferred”.
He conceded that acid water has already breached the ¬“environmentally critical level” – a vital parameter for preventing the contamination of ground water systems – but said that the original measure had been “a conservative estimate based on information ¬available in late 2010”. It could be gradually raised, subject to monitoring.
Responding to claims that the two-year delay could result in cost ¬escalations and possible injuries to construction workers who will now have to work around the clock to catch up, Ratau said the contractor would have to follow a “fast-tracked schedule” to meet the revised level, but that this would not incur additional costs.

Nothing but spin

But Tony Turton, of the Centre for Environmental Management at the University of the Free State, said the delay indicates that, “while the government makes public statements that its commitment to the AMD solution is high, the reality is that it is low on the agenda”.
Turton said AMD had decanted into the western basin in 2002, and did so again this year. At its peak, 60 million litres a day bubble to the surface at 18 Winze Shaft in Krugersdorp, he said. This water is now flowing into the Crocodile River, upstream of Hartbeespoort Dam, and the Mooi River, upstream of the Vaal River. It has already affected residents with boreholes, and “there is also a growing fear among rural communities that borehole water is contaminated”.
He said agriculture has also been affected in some areas. In particular, the Coetzee Dam has been heavily contaminated with uranium. “A farmer breached the wall to allow the trapped -sediment to flow out, creating a uranium plume that entered the Potchefstroom drinking water system.”
According to research by North West University, uranium is moving into the food chain, Turton said.
“We know, with a high level of scientific confidence, that the western basin is an ecological disaster … we now see the rapid movement of highly contaminated water though the aquifer. The same will occur, with a reasonably high level of certainty, when the environmentally critical level is breached in any other mining basin, particularly if the aquifer is dolomitic.”
Turton rejected Ratau’s explanation that the critical level had been recalculated in the eastern basin, pointing out that nothing has changed in the rocks underground.
“The claim that the level has been redefined, simply to justify that a delay in the awarding of the Ekurhuleni contract will not cause any damage to the environment, is in my professional opinion nothing more than spin,” he said.
The absence of a clear government policy on mine residue areas poses “a growing risk to millions of people who are living on land that is increasingly geotechnically unstable and contaminated by uranium”, said Turton.
PG Mavundla Engineering project manager Philani Mavundla said that, given his experience with big government contracts, it was “humanly possible to complete the task before disaster could occur”.
In the longer term, a controversial proposal for the remediation of AMD envisages treating it to a potable level and using it to supplement Rand Water’s water supply in Gauteng.
This proposal apparently still awaits Cabinet approval.
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Plant contractor denies closeness to Zuma


The winner of the R1-billion contract for the eastern basin acid mine drainage treatment project is also a key contractor in a giant hydroelectric scheme in KwaZulu-Natal. Its price has reportedly jumped threefold since its inception.
PG Mavundla, owned by flamboyant former Greytown mayor Philani Godfrey Mavundla, is part of the CMC Impregilo Mavundla joint venture that is building Eskom’s Ingula pumped storage electricity project in the Little Drakensberg, near Van Reenen’s Pass.
This week Eskom spokesperson Andrew Etzinger said the overall cost of Ingula now stands at R26 billion. In 2012 Business Day reported that the initial cost of the project was a third of this amount, at R8.9 billion.
On completion, originally set for later this year, it will be Eskom’s third-largest pumped storage scheme, with an output of 1 332 megawatts.

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