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Nigeria, Ogun State, Abeokuta

Effects of waste dumps on groundwater quality in Abeokuta and environs

The study area, Abeokuta and its environs, is located in Ogun State, south western Nigeria. It is defined by latitudes 07° 3.0´ to 7° 17.0'N and longitudes 003° 14.0' to 003° 28.0'E and falls within 1:100,000 Sheet 260 Abeokuta and covers an area of 625km2.\r\n\r\nThe objective of the project is to study the hydrogeological characteristics of the area and the impact of waste dumps on the water quality. \r\n\r\nThe area is predominantly underlain by rocks of the Basement Complex and partly by the Cretaceous Sedimentary rocks of the Dahomey Basin. The rocks encountered in order of abundance are migmatized biotite-garnet gneiss, red sand, biotite schist, biotite-garnet-gneiss, coarse porphyritic granite, porphyroblastic gneiss, biotite granite, pegmatite and quartz vein. \r\n\r\nThe physical, chemical and microbial analyses of water samples (surface and groundwater) showed high conductivity, high concentration of trace elements and the presence of pathogens (Esherichia coli) in nearly all the water samples that is within a range of 14 - 180 CFU/ml indicating anthropogenic influence on the groundwater quality. The water samples are all beyond the W.H.O. and S.O.N accepted drinking water standards for human consumption.\r\n\r\nRemediating measures such as provision of pipe-borne water, construction of central sewer system, enactment and enforcement of sanitary bye-laws and location of waste dumpsites are recommended to ameliorate the problems of groundwater pollution in the area. \r\n

Inserted in the reports are the following maps (1:50,000): Location map, Accessibility map, Drainage map, Geological map, and Wet & Dry Seasons Water Elevation Contour maps.