JOHANNESBURG (miningweekly.com) – The South African government is considering turning to the private sector to help it close the prevailing funding gap to implement projects to deal with the serious acid mine drainage (AMD) problem being experienced across the Witwatersrand basins, Water and Environmental Affairs Minister Edna Molewa revealed on Thursday.
It was estimated that R924-million was needed to implement a short-term AMD solution for the region, but that even more resources would be required for a comprehensive long-term solution.
However, the National Treasury had only made R433-million available. Therefore, the Department of Water Affairs (DWA) and Department of Mineral Resources (DMR) would explore the possibility of testing the “open market” for input in finding a sustainable solution.
Molewa expected the responses to address all aspects of AMD including institutional matters, financial matters, technology and the operation and implementation of the treatment plants in the Witwatersrand.
“Once we have more clarity on the way forward and on the process that could be followed to speed up the long-term solutions, my department will make further announcements in this regard,” Molewa stated, while stressing the need for a “smooth integration” between the short-term and long –term solutions.
DWA acting director water quality management for Gauteng Marius Keet agreed that linking the long- and short-term solutions was crucial in achieving success. “The challenge is to ensure interaction between the short- and long-term solutions to secure business case and thereby protect valuable water resources,” he noted.
The design philosophy for the short-term solution to AMD treatment in the Witwatersrand basins stipulated that facilities should have a lifespan of 30 to 50 years and would, thus, comprise the first phase of any longer-term solution.
Giving delegates an update on AMD treating projects in the Witwatersrand basins Keet said the current mine water status of the eastern basins was 588 m below surface (mbs) in February, where the environmental critical level (ECL) was 290 m. In the central basin, levels were recorded to be 353 mbs in March, well below the ECL of 174 m, while the ECL had been breached in the western basin resulting in surface decant.
The treatment plants were expected to halve the amount of sulphates, or salts, in the decanting water.
The infrastructure included in the short-term solution included pumps, partial treatment using hydro desulphuriser (HDS), sludge disposal facilities and pipelines.
Key to the immediate remedy was an upgrade to Rand Uranium’s treatment plant to a capacity to about 36 Ml/d from its current capacity of between 10 Ml/d and 12 Ml/d. The project was on schedule to be implemented during April.
“Currently about 36 Ml/d of AMD is running into Tweelopiespruit, of which only about 12 Ml /d is being partially treated. We hope to have no untreated water discharging into the river by April,” Keet said.
The treated water would then be discharged into Tweelopiespruit, while sludge would be deposited into the Wes Wits pit, with the aid of Mogale City.
At the central basin the aim was to construct a new HDS plant next to the South West Vertical shaft that would have a capacity of 84 Ml/d. Treated water would be transferred to the Elsburgspruit and the commissioning date was set for April 2013. Sludge would be disposed with the support of DRDGold.
On the eastern basin, a 110 Ml/d HDS plant would be built and treated water discharged into the nearby Blesbokspruit. The plant was expected to be commissioned in June 2014.
The DMR had also appointed the Council for Geosciences to identify and stop ingress in seven basins including the eastern, central and western basins. The feasibility of additional ingress control measures in the central basin was being investigated.
Further, Molewa said the feasibility study for a long-term solution for AMD in the Witwatersrand, which started in January, was expected to be completed by February 2013. The study focused on investigating possible management scenarios, an analysis of technical options and the optimal infrastructure configuration.
Molewa urged the business sector, general public and government to stand together in finding a solution to the AMD emergency.
The opposition Democratic Alliance (DA) welcomed the intervention, which it said echoed similar calls made by the party, as well as various environmental groups, since 2009.
“The problem with AMD is not the absence of a desire for a collective effort or possible solutions, but rather a lack of meaningful action and commitment of resources to the problem. Hopefully the Minister will back up her call by immediately leading a clear, open and participative process rapidly developing solutions and instantly implementing them,” the DA said in a statement.