Abstract
Health concern about possible impact of the cemeteries in Nigeria on the water supply has prompted this research. The research engaged Vertical Electrical Sounding (VES), 2- Dimensional and 3-Dimensional imaging (tomography) to investigate the presence and migrationof lea plumes in the cemetery, hydro physicochemical analysis of water samples (for multivariate analysis) and computation of time- lapse to detect the time rate of migration in both the vertical and horizontal directions. The field work covered a time ?? lapse of six months (June 2017 to December 2017). Three sites at the peripheral of the cemetery and a reference site were used as water sample sources. Groundwater samples were collected and analyzed. The electrical esistivity data collected in parallel equidistant lines was processed to obtain geoelectric models using Res2dinv and the second survey data was also merged and inverted as a single 3-D data set using Res3dinv software and Voxler 4.0 to give 3-D block model and volumetric analysis of the leachate plume. Multivariate analysis involving Principle Component Analysis, Cluster Analysis and computation of Water Quality Index, was also carried out to identify the major contaminants and their levels of contamination. The study showed that the status of the groundwater at the vicinity of the cemetery is fit for drinking and other domestic purposes though with some degree of contaminations. The main parameters constituting the contaminants include pH, EC, Cl, NO 3, SO 4 and Na, which are mostly influenced by the on-site activities in the cemetery. The leachate plumes in the cemetery migrate vertically and horizontally at different rates. The research also showed that repeated ERT surveys can track movement of leachate plume emanating from decomposed dead bodies over time in active cemetery.
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