Sedimentation ponds are basins hollowed out of the ground which are used, for example, for purifying raw materials excavated from mines with the help of water. The water resulting from the washing process can either be re-used for the same process or released into the water source again once it has been separated from the substances suspended in it, most of them the minerals contained in clay. This process takes place in smaller sedimentation ponds near the open-cast mines. The clarified water is pumped off again after the sedimentation process. A secondary biotope develops very quickly on the fringes of these temporary pools. It contains a very interesting range of flora and fauna in a natural habitat, including species that have disappeared from the present-day cultural landscape.
The model at InfoPoint No. 9 uses a swinging perspex barrel to illustrate how the process of separation takes place in the sedimentation pond – a bit like a snowstorm globe at Christmas!