GEOPHYSICAL MAPPING OF SHALLOW AQUIFER VULNERABILITIES INDEX: A CASE STUDY AT FUPRE CAMPUS

Groundwater is a crucial resource for sustaining life and supporting economic activities, especially in regions with limited surface water availability. However, shallow aquifers, which serve as vital sources of potable water, are increasingly vulnerable to contamination due to surface activities like agriculture, waste disposal, and industrialization. This study focuses on the geophysical mapping of shallow aquifer vulnerability at the Federal University of Petroleum Resources (FUPRE) campus to assess the risk of groundwater contamination. Vertical Electrical Sounding (VES) using the Schlumberger array configuration was employed to investigate the subsurface resistivity variations, providing insights into the geological structures and the distribution of potential aquifer zones. Five VES points were strategically surveyed across the study area, and apparent resistivity values were recorded at varying electrode spacings to determine the subsurface layering and identify zones susceptible to contamination. The results indicated a layered subsurface structure, with a relatively homogenous top layer of moderate resistivity, likely composed of unconsolidated sediments. This was followed by deeper, more resistive layers, suggesting compacted sediments and potentially impermeable formations such as weathered bedrock. The increasing resistivity values at greater depths reflect a transition to less permeable, denser geological layers, reducing the potential for aquifer storage in these zones. The identified vulnerability zones, characterized by lower resistivity values, indicate areas with higher risks of contamination due to their closer proximity to the surface and lower natural filtration capacity. This study provides a comprehensive assessment of aquifer vulnerability, which is essential for effective groundwater management and protection. The findings highlight the need for targeted land-use planning and protective measures to safeguard groundwater resources in the FUPRE campus area. Recommendations include implementing regular groundwater quality monitoring, adopting stricter waste disposal regulations, and employing advanced geophysical techniques for more detailed subsurface imaging. The methodology and results presented in this study serve as a valuable reference for future hydrogeological investigations aimed at mitigating the risks of groundwater contamination and ensuring sustainable water resource management.