Abstract:
The metals cadmium, chromium, copper, iron, mercury, manganese, molybdenum, nickel, titanium, vanadium, zinc, aluminium and the non-metals arsenic and boron are discussed from a theoretical viewpoint with specific attention to their presence in nature, as well as their mobility and availability with pH variation. A project was initiated to determine the possibility of pollution by the metals from the sediment to the water phase in the Koekemoerspruit/Orkney area of the Vaal River catchment. This was done by firstly doing a total digestion procedure, and secondly by using a pH-dependent sequential extraction procedure.