Geo-electric method applied to groundwater protection of a granular sandstone aquifer

The geo-electric properties of the granular sandstone aquifer of Lafia and environs were evaluated for the purpose of groundwater management. Vertical electrical sounding (VES) using Schlumberger electrode array with a maximum half current electrode separation of 400 m was employed. Interpretation of the VES results showed that the area is characterized by 4–5 geo-electric subsurface layers, viz. topsoil/laterite, sandy clay, clayey sand, sandstone and shale while the APC varies from very good 4%, good 36%, moderate 30% and weak–poor 30%. Approximately, 82.22% of the study area is practically noncorrosive, while parts of the southern, south-western and central parts fall under slightly corrosive (13.33%) to moderately corrosive (4.5%). Groundwater quality varied from excellent (13.33%), good (30%), poor (40%), very poor (13.33%) to unsuitable (3.33%) for drinking purpose. Most locations with good APC do not translate into locations with good water quality syndicating a non-direct relationship between APC and groundwater quality for drinking purpose in the study area.