Delineation of Groundwater Contamination Using Self Potential Method in Effurun, Delta State, Nigeria

Abstract

Spontaneous Potential profiling has been carried out around a dumpsite in Effurun near Warri, Delta State, Nigeria. This is with a bid to determine qualitatively the presence of contaminant in the groundwater around the area due to electrochemical and electrokinetic processes arising from arbitrary disposal of both domestic and industrial waste. The study was carried out by engaging two different electrode configurations, which include the gradient and the fixed base arrays. This is to reduce or eliminate cumulative errors and electro - telluric noise connected with variations in the earth's magnetic field and other cultural sources. The data acquisition was carried out along the two orthogonal traverse lines. Electrode spacing of 5 m and 10 m in both techniques were adopted. Also, the data was acquired during the raining and dry season, to determine the effect of climatic changes on leachate generation and migration. The profiles generated show high positive potential of up to 70 mV outside the dumpsite area to as low as -60 mV around the dumpsite area using the gradient array, and 120 mV to -30 mV using the fixed base array in both the raining and dry seasons. This low and negative potential readings around the dumpsite area could be the confirmation of the redox activities taking place at depth, and contaminating the aquifer and groundwater.

Keywords: electrokinetic, electrochemical, contaminant, self potential, electrodes