Vulnerability Assessment of Soils and Groundwater Resources To Surface Induced Contamination Using Goeelectrical Methods.

Abstract

This study entails the vulnerability assessment of soils and groundwater resources to surface induced contamination by solid wastes from a dumpsite in Port Harcourt Metropolis, Rivers State. The objective is to evaluate soil protective capacities on the groundwater system of the area using the Dar-Zarrouk parameters.Vertical Electrical Sounding (VES) and 2-D Electrical Resistivity Tomography (ERT) were integrated in the study. A total of four (VES) and two (ERT) were occupied with the use of the Schlumberger and Wenner electrode configurations respectively for subsurface characterization. Results of the VES reveal the lithology to be mainly of lateritic sand to sands of varying grain sizes and thicknesses. The VES show 4 to 5 geo-electric layers with different type curves. Leachate plume were delineated in the 2^ndlayers of VES 1, 2,3 and 4 and 3^rd layers of VES 1and 3 with resistivities range of (24.83–85.66) Ωm and depth range of (4.58–20.07) m. The 2-D resistivity tomography identified contaminants within and around the dumpsite. Contaminant leachate plume with low resistivities between (3.7and 98.8)Ωm occur at the surface points (0.469m) and depths of over 16m, in the entire area.