Evaluation of Aquifer Protective Capacity and Soil Corrosivity Using Vertical Electrical Sounding Method In Badeggi Village, Niger State Nigeria

Abstract

A geoelectric survey was carried out in Badeggi under Katcha Local Government area of Niger State. The aim is to evaluate the aquifer protective capacity and soil corrosivity of the overburden units in the study area using vertical electrical sounding method. G41 Resistivity meter was employed to obtain forty VES points within ten profiles, with the interval of 50 m between the profiles. This was done using the Schlumberger electrode array to obtain the data and was modelled using computer iteration (Winresist software). The vertical electrical sounding curves with layered model comprising of the apparent resistivities, layer thicknesses, and depth were obtained from the software. The information obtained was used to evaluate longitudinal conductance and transmissivities of the layers. The results show generally low resistivities across the survey area and an average longitudinal conductance variation from 0.1171 Siemens in VES 11 to 0.925 Siemens in VES 23, almost the entire area giving values less than 1.0 Siemens. The average transmissivity values ranges between 91.62 Ωm in VES 15 to 1339.4 Ωm in VES 33. The field data gives a resolution with 4–5 geoelectric layers and the observed frequencies in curve types include: 40% of QH, 35% of Q, 17.5% of QHK and 7.5% of QKH. Using the longitudinal unit conductance (S), the protective capacities of the study area were classified as 20% weak, 0% poor, 72.5% moderate, and 7.5% as good. The corrosivity ratings of the study area show that 42.5% is slightly corrosive and 57.5% is practically non corrosive. The results reasonably provide information on areas where any form of agricultural activities, industries can be sited and iron pipes can be laid in order to safeguard the hydrological setting for resident’s safety in the study area. Regions with moderate/good protective capacity are good sites for locating boreholes.