Evaluation of some geophysical and physicochemical characteristics of soil and groundwater resources in Sapele, south-south Nigeria

Abstract

This study evaluated some geophysical and physicochemical characteristics of soil and groundwater resources in Sapele, Delta Sate of Nigeria using various standard techniques. The results of the resistivity data shows that a high resistive plume with resistivity > 12,000 Ohm-m has penetrated the soils beyond 21m beneath the surface in most parts of the surveyed area. The water samples shows high acidity with pH values in the range 4.6-5.1. Total Dissolved Solids (TDS) is low 46.40- 47.98mg/l and conductivity ranges from 72.80-78.8 μS/cm, There is no incidence of heavy metal pollution, only Iron is high (0.772-0.915mg/l). Total petroleum hydrocarbons-(TPH) as oil and gas revealed by gas chromatography result is below detection level (<0.031mg/l), this can be attributed to the sealing of the confined aquifer by impermeable clay. The average permeability of the soil is 5.514 x 10^-3cm/s indicating good drainage condition. The results have shown that shallow boreholes are polluted and the soils of the area are acidic. Groundwater of the area need treatment before it can be consumed and periodic integrated methods of investigation should be carried out in the study area.

Keywords: Contamination, Groundwater, Imaging, Resistivity, Soil