Application of Electrical Resistivity and Hydrochemical Methods to Investigate Agriculfural Pollution in some Parts of Ojo, Lagos, Southwest, Nigeria

The environmental implication of agricultural activities in Oko-efo area in Ojo Local Government Area of Lagos State on groundwater has been carried out using geophysical and hydrochemical methods. The geophysical method involves vertical electrical sounding Wihile the hydrochemical analyses, using standard analytical methods were carried out on the groundwater samples from both hand dug wells and bore holes in the area. Two hundred meters (200m) away, four vertical electrical soundings were also carried out within the study area to serve as control. The geophysical layers were delineated from interpretation of vertical electric sounding data and the polluted region showed resistivity value between 32-38 Ωm. The variation of Mg, Zn and Fe in both shallow wells and borehole water wnhin the area support the evidence of pollution from Agricultural practices as well as the vertical electrical sounding data got at 200m away.