ABSTRACT
ABSTRACT: The Botswana Department of Geological Survey (DGS), in collaboration with the German Federal Institute for Geosciences and Natural Resources (BGR), has established an Environmental Geology Division. The overall objective of this bilateral technical co-operation project was to enhance the capacity of the Department of Geological Survey to contribute to the protection of the environment in Botswana. During her first five years of operation (2000-2005), the division emphasised groundwater quality studies mainly carried out in the eastern part of the country. The results of the studies show that nitrate pollution is prevalent in many aquifers underlying built-up areas, mainly due to discharge from pit latrines. Even in rural areas groundwater nitrate pollution is a problem, although in a more haphazard fashion and due to anthropogenic and natural sources. In addition to nitrate pollution, the high levels of salinity are the most common groundwater quality concern in Botswana; especially the chloride, sodium, and sulphate levels. Elevated salinity levels render groundwater unsuitable for human and livestock consumption in many places, in particular the semi-arid Kalahari region. There are also a few cases where concentrations of trace elements (heavy metals) are reason for concern. Although most of the affected areas are associated with mining (gold, base metals), there are also instances where elevated concentrations appear to stem from geological formations.
