Physico-chemical Properties of Soil Samples and Dumpsite Environmental Impact on Groundwater Quality in South Western Nigeria

Abstract

Physiochemical and microbial analysis of water samples from hand-dug wells were carried out around active dumpsite and/or of soil samples to ascertain the effect of wastes on the groundwater and soil quality. Soil samples were collected up to a depth of 100cm with the aid of soil auger while water samples were collected inside a 2L PVC bottle. Soil pH, EC, % OM, %OC values ranged from 5.45-6.45, 5.03-6.63, 2.39-9.14, and 1.39-5.30. The mean values of soil’s pH, EC, % OM, %OC are high when compared to control. For water samples, the parameters of interest for microbial analysis are: coliform count and E. coli while parameters determined for physiochemical analysis are: pH, Total Dissolved Solid (TDS), Electrical Conductivity (EC), Hardness, Carbonate, Bicarbonate, Chloride, Nitrate, Sulphate, Calcium, Magnesium, Potassium and Sodium ions. Microbial analysis revealed severe pollution in all samples while most of physiochemical parameters indicated traceable pollution, which were below the World Health Organization (WHO) standard for human consumption as well as the Nigerian Standard for Drinking Water Quality (NSDWQ) limits. However, Well 5 which is close to the landfill has high values for all analyzed parameters when compared with other wells.