Environmental impacts associated with an abandoned mine in the Witbank Coalfield, South Africa

Mining at Middelburg Colliery in the Witbank Coalfield commenced at the tur n of the last century. Initially, there was little environmental degradatio n associated with mining activities; however, in the late 1930s, a pillar-r obbing programme commenced. This has had a marked effect on the environment . Some of the most notable primary effects include subsidence, the appearan ce of tension cracks a! the surface and crownhole development. Secondary ef fects include spontaneous combustion of the coal worked, as air has been pr ovided with ready access to the mine, accelerated subsidence due to the str ength of many pillars being reduced by burning, and a marl;ed deterioration of groundwater quality in the area due to the seepage of acid mine drainag e from the mine. Spoil heaps also form blemishes on the landscape. These co ntain significant amounts of coal and have undergone spontaneous combustion . The deterioration in the duality of water has led to the decimation of ve getation in some areas and the eradication of aquatic flora and fauna in a nearby stream. (C) 2001 Elsevier Science B.V. All rights reserved.