Hydrogeochemical–geophysical investigations of groundwater quality and susceptibility potential in Ikot Ekpene–Obot Akara Local Government Areas, Southern Nigeria

Abstract

Groundwater contamination is of global concern. The study area (Ikot Ekpene–Obot Akara Local Government Areas) continues to experience a swift increase in human population and associated economic activities, leading to the generation of more waste. The fundamental goal of this work is therefore to weigh up the groundwater standard through hydrogeochemical investigation of groundwater samples and the susceptibility potential of the economically exploited aquifer units in the area. The results of the electrical geo-sounding data acquired at 28 locations in the area reveal three to four lithological successions comprising fine/coarse sands and gravels amid patches of thin clay interbeddings at several places. The primary aquifer is the third layer, which is between 10.5 and 101.5 m deep with resistivity values between 359.4 and 2,472.8 Ωm. The hydrogeochemical evaluation of groundwater samples in the area shows that the measured physicochemical parameters are well within the World Health Organization’s acceptable limits except for lead and nickel ions. The groundwater quality and susceptibility potential maps generated seem to correlate well and clearly demarcate the poor groundwater quality/high susceptibility potential zones. These maps are useful tools that could aid policymakers in successful groundwater management in the area to meet the needs of the populace.