Geoelectric investigation of the suitability of a proposed foldot ventures potable water factory site, Ipinsa, near Akure, southwestern Nigeria

Abstract

This study is aim at determining the suitability of sitting a potable water factory within Chief Akin Omosebi layout off Ipinsa-Ilara road, near Akure, Ondo State, Nigeria by evaluating the groundwater potential, the aquifer overlying layer protective capacity and the foundation beds competence of the area. A total of twenty (20) vertical electrical soundings (VES) data were  acquired along five (5) traverses using Schlumberger array with maximum half-current electrode separation of 150 m. Three curve types were delineated in the area (K, KH and KQ). The VES  results delineated three to four geoelectric layers across the study  area. The resistivity of the top soil, lateritic weathered layer, clayey sand weathered layer and weathered bedrock/fresh bedrock varies from 187 - 1212, 682 - 4164, 219 - 1157 and 77 - 3525 ohm-m respectively. This study reveals that the area is  characterized by high groundwater potential and competent subsurface layers that can serve as foundation bed, but the aquifer layer must be well protected from pollution since the overlying layer(s) longitudinal conductance is less than 1.0 mhos which  indicates that the underlying aquifer unit(s) are vulnerable to surface pollution.

Keywords: Groundwater potential, aquifer overlying layer,  protective capacity, longitudinal conductance and foundation beds competence.