The R225-million set aside to deal with acid mine drainage (AMD) would not be enough, and closer to R750-million would be needed to address the problem successfully, Johann Claassens from the Trans-Caledon Tunnel Authority (TCTA) said on Tuesday.

Claassens was addressing Parliament’s Portfolio Committee on Water and Environmental Affairs on AMD.

Dr Henk Coetzee from the Council for Geoscience said that urgent action was required in the Western basin of the Witwatersrand gold fields as acid mine water is already decanting to the surface and impacting on the Cradle of Humankind World Heritage Site.

AMD is also affecting the Krugersdorp game reserve, which is an area where “there is no longer a functioning ecosystem”, Coetzee told Parliament.

In the Western basin, where there are several nonoperational mines, 17.7 Ml/day of untreated AMD is currently decanting into the Tweelopiesspruit, with flows having reached peak levels of 50 to 60 Ml/day during the past summer.

Rand Uranium and Mogale Gold have been the most active in this region in assisting the Department of Water Affairs to address the problem.

Rand Uranium is pumping out and neutralising 12 Ml/day and the company’s plant is being upgraded to 30 Ml/day. The intention is also to upgrade the Mogale Gold treatment plant to 24 Ml/day.

Even though decant of AMD in the Western basin may be halted with these treatment plant upgrades, it could take up to two years to reduce the AMD levels in the basin to below the environmental critical level (ECL). The ECL is defined as the level within a mine void where AMD begins to contaminate the surrounding groundwater or surface water system.

Claassens said that in addition to the Rand Uranium and Mogale Gold plant upgrades, the construction of a new plant to pump and neutralise AMD in the Western basin is due to start in January 2012, but will not be commissioned until September 2012.

Portfolio committee chairperson Johnny de Lange expressed his dismay at what he felt was an unnecessarily lengthy process.

“It can’t be that while our waters are being polluted we are going to sit back,” De Lange said. “We are going to take months and months to do this once we have agreed on what the solution is [already]. It just seems wrong.”

Coetzee and Claassens said immediate intervention is also required in the Central Witwatersrand basin, which at the current average rate of rise of AMD of 0.4 to 0.6 m/day will decant into the Boksburg area by as early as March 2013, should no intervention be taken. However, AMD could reach the ECL by June next year.

Coetzee said the crisis in the Central Witwatersrand basin was precipitated by East Rand Proprietary Mines halting its pumping and neutralisation process of 60 Ml/day after its pumps were flooded. While the ECL level in this region is 173 m below the collar of the south-west V shaft, Central Rand Gold (CRG) has an interest to keep the water level below 400 m in order to continue operations in this area. As a result, CRG is assisting in the Central basin and has ordered pumps, which when installed, will maintain the water level of 400 m.