2D Resistivity Imaging Investigation of Solid Waste Landfill Sites in Ikhueniro Municipality, Ikpoba Okha Local Government Area ,Edo State, Nigeria.

Abstract

2-D resistivity imaging was used to study the aquifer vulnerability to surface pollutants near solid waste landfill sites in Ikhueniro, Edo state, Nigeria. Five 2-D resistivity tomography surveys were utilized for the subsurface aquifer characterization. The results of interpretation of the data suggest that with the aid of the 2-D resistivity tomography, two distinct pollutants were mapped and identified within and around the landfills. These are compounds of anomalously high resistivities between 808?m and 4069?m suspected to be landfill gases (Ammonia, Methane, Sulphur (IV) Oxide, or Carbon (IV) Oxide) at depths exceeding 17.2m, and low resistive leachate contaminant plumes of resistivities between 9.45?m and 86.6?m at depths between 0.75m to more than 14.4m, implying that the aquifer is contaminated. These contaminants are migrating in depths and distance away from the landfills because of the porous and highly permeable sandy layers into the aquifers. Due to the vulnerability of these aquifers to surface pollutants, the sitting of dumpsites without adequate lining of the base should be discouraged in the metropolis, considering their implications on the soil and groundwater.

Keywords: Solid Wastes, Aquifer Vulnerability, Leachate Plume