OVERVIEW OF THE IMPACT OF MINING ON THE ... - IIED pubs

None obtainable in time for this report, but data are available from the Botswana Department of Water Affairs.
4.3.6 Implications for water quality and quantity management
Very minor impacts can be anticipated from the Morupele-Moijabana Colliery, in terms of possible elevated
concentrations of suspended solids, total dissolved salts and sulphate. Very small localized impacts of acid
mine drainage can be anticipated.
4.4 The Motloutse sub-catchment
4.4.1 General description
4.4.1.1 Hydrology
The Motloutse River and its minor tributary streams rise in a range of low hills at the eastern edge of the
Kalahari Desert, to the south-west of Francistown. The Motloutse River flows in an easterly direction to join the
Limpopo River some 40 kilometres upstream of the confluence of the Shashe and Limpopo rivers. The river is
normally seasonal and only carries surface water during the summer months.
The Motloutse River has a small water supply dam near the town of Selibe-Phikwe and this provides the main
source of domestic water for the town and mine, as well as water drawn from the North-South Pipeline. Several
small farm dams and boreholes provide water for stock watering in several parts of this dry sub-catchment.
4.4.1.2 Geology
The rocks of the Kalahari Craton underlie this sub-catchment. Large areas of the sub-catchment have
exposures of Gaborone and Mahalapye granites, as well as rocks of the Palapye Suite and the Lebung
Formation of the Karoo System. The Karoo System rocks in the area contain economic sources of coal. The
Selibe-Phikwe copper-nickel mine is located on a contact zone of intense mineralization at the edge of a large
Gaborone Granite formation.
4.4.1.3 Pedology, agriculture and land use
Soils in the sub-catchment can be divided into five groups:
• Moderately shallow, coarse-grained feldspathic to kaolinitic sands, derived from the Gaborone and
Mahalapye granites;
• Moderately shallow sandy loams, formed from gneisses; and
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