Determination of Aquifer Protective Capacity Using Dar-Zarrouk Parameters at Sabo Area Okitipupa, Ondo State Southwestern Nigeria

Abstract

The reasons for investigating for the aquifer protective capacity is not far-fetched as this determine the integrity of the source of our water. Mostly, more than 80% of the world depends on groundwater because of the general belief that the cleanest water can be found underground compare to surface water. Whereas it is of importance to do proper investigation to determine the integrity of the groundwater as most of the activities of man on earth can pose a threat to the underground water. It has been a known fact that geophysical method plays an important role to probe the sub-surface to gather information by measuring the physical properties of the earth. Therefore, vertical electrical sounding found to be cheap was used to investigate the study area groundwater integrity as it happens to fall on an abandoned dumpsite area turned to residential area. A total of seventeen (17) vertical electrical soundings were acquired. Maximum of two VES points were investigated in each of this traverse covering electrode distance of AB/2 of 100m.Furthermore, Dar-Zarrouk parameters involving Longitudinal conductance and traverse resistance was used to delineate the aquifer protective capacity of the study area. It was revealed that the longitudinal conductance varies between 0.01 to 0.19 and the traverse resistance varies between 228.4 to 39000. This value for the longitudinal conductance fall between the 0.01 – 0.05 in the southern and southeastern part while the northwestern part varies between 0.35-0.85.  Therefore, this study area is not a suitable place for groundwater consumption considering this particular study area is an area of abandon and active dumpsites as the study area shows that majority of the sounding stations are poorly protected.