ABSTRACT
ABSTRACT: The aquifer of the Cap-Vert Peninsula (region of Dakar) is confined in the west (infrabasaltic aquifer) and unconfined towards the east. In this region groundwater supplies the majority of the urban population. Anthropogenic activities result in high nitrate contents widely exceeding the heath standards. The existing nitrate pollution, originating from sanitation, has steadily increased over the years. This is related to the inadequacy of the sanitary installations and garbage collection infrastructure in the densely populated suburban area (east of Dakar). In this zone, the high vulnerability of the shallow, unconfined aquifer under sandy cover facilitates the infiltration of nitrates from household latrines and leachate from of waste disposal. Chemical contamination is accompanied by localised bacteriological contamination, exposing populations directly using wells to risks of sickness. Pollution tends to become widespread towards the infrabasaltic aquifer, since boreholes in to the suburban area are highly contaminated.
