Delineation of Oil – Polluted Sites in Emohua LGA of Rivers State Using Resistivity and Induced Polarization Techniques

Abstract

A geophysical investigation was conducted in Obele Community in Emohua Local Government Area of Rivers State, Nigeria using the dipole-dipole electrode configuration to assess the impact of oil spillage on the environment. Oil spillage occurs due to a number of causes which include corrosion of pipelines, sabotage and oil production operations. Sabotage and oil siphoning has become a major issue in the Niger Delta States as well contributing to further environmental degradation. The study used vertical electrical sounding (VES) and resistivity/IP tomography to examine the extent of oil contamination in the soil and groundwater. The results showed that the study area is heavily impacted by oil spillage, with high resistivity values (up to 10,000Ω-m) indicating the presence of hydrocarbons. The contamination was found to be widespread, affecting both the soil and groundwater and originating from a possible point source along a pipeline section. The study also revealed that the aquifer in the area is unconfined, with high hydraulic conductivity values, making it vulnerable to contamination. The groundwater flow direction was found to be from NW to SE, indicating the potential direction of contaminant migration. The study recommends cleanup and remediation efforts to mitigate the environmental impact of the oil spillage. Going forward, security operatives should adopt a more robust way of handling apprehended vehicles and vessels containing stolen crude oil (oil Bunkry).