Abstract: This work entails evaluating the protective capacity of the aquifer using the Vertical Electrical method to assess the vulnerability of aquifers using resistivity parameters of the upper most geo-electric materials layer overlying the aquifer. Seventeen (17) vertical electrical sounding (VES) points were conducted at various locations within the study area. The result of the study shows that the longitudinal unit conductance values obtained from the study area ranges from 0.003864 to 0.059655mhos. The study revealed that aquifers within the area are susceptible to pollution since the protective capacities of the aquifers are generally poor. Vulnerability map of the study area produced from the longitudinal unit conductance indicates that the North central, northeast and south central of the map shows that the vulnerability rate is better off than the others i.e. the northwest, southwest and part of the eastern side of the map. Sand layer seems to provide lower longitudinal conductance generally in the study area and hence poor protective capacity. It can be inferred from this study that sandy soils have poor protective capacity due to its pore space and lessabsorption capacity compared to clayey and shaly soils thus providing a lesser protective capacity for groundwater. The results of this study have provided reliable information about the protective capacity of the materials overlying the aquiferous unit which should be considered for planning, development, siting of prospective water resource projects and serves as a guide for groundwater pollution control in the study area.
Keywords: Vertical electrical sounding, vulnerability assessment, longitudinal conductance, protective capacity, groundwater.