Synthesizing vulnerability indices within a diverse lithological context: Corollaries for groundwater quality assurance and surface layer corrosiveness of Lokoja Geomaterials, Nigeria

Abstract

ABSTRACT This study provides prototypical evaluation of groundwater vulnerability to contamination and soil corrosivity in the Lokoja region, central Nigeria. By combining the aquifer vulnerability index, integrated electrical conductivity, groundwater confinement overlying strata depth to water table (GOD), and electrical anisotropy coefficient (λ) derived from lithological composition, resistivity, and layer thickness, the study identifies substantial vulnerabilities in the groundwater resources. Findings indicate that over 70% of the region is moderately to very highly vulnerable to groundwater pollution, especially in the eastern and southern parts, highlighting the need for tailored groundwater management strategies in highly vulnerable areas, covering 40% of the region. Corrosion potential varies spatially, with 80% of the upper layer being minimally corrosive and around 45% of the lower moisture-rich layer showing moderate to significant corrosiveness, emphasizing risks in central and northern zones associated with lithological compositions and moisture content. These accentuate the necessity of rigorous monitoring programs and strict land use regulations to protect aquifers and infrastructure. This research underscores the value of proactive management for safeguarding groundwater resources, providing an invaluable framework for decision-making and resource allocation to tackle contamination and corrosion risks. Importantly, the research addresses a significant research gap in a region with limited scientific exploration.