AMD is expected to reach environmental critical level – the highest level that mine water can be allowed to rise in the mine void before adverse impacts can be detected – by September this year.

A short-term solution, the construction of a pump station has started on an old mine east of Germiston, but this is only expected to become operational by November – two months after the critical level is reached.

Should critical levels be reached, one of South Africa’s historical museums – the underground mine museum at the Gold Reef City theme park – could be flooded, and might have to be moved.

The Trans-Caledon Tunnel Authority was contracted to implement the short-term solution, which involves pumping 27 megalitres, 57 megalitres and 82 megalitres of acid mine drainage out of the Western, Central and Eastern mine basins respectively on a daily basis, treating it and releasing it into the Vaal River system.

The Department of Water Affairs has already stopped acid mine drainage from decanting (emptying out) into the Western Basin by upgrading an old Rand Uranium plant in Carletonville, and pumping the drainage from the basin.