Impact of Dumpsites on Groundwater Contamination in Selected Settlements in Irewole and Isokan Local Government areas, Osun State, Nigeria

Abstract

This study examined the spatio-temporal variation in the physico- chemical characteristics of ground water across the study area. This was with a view to determining the impact of dumpsites on ground water quality in the study area. Ground water samples were taken twice (once in the dry season and once in the wet season). These samples were taken from wells within 150 m proximity of a dumpsite using 1 litre high density polyethylene bottles. A control point was purposely picked, 1 km away from any noticeable dumpsite. The water samples were analyzed for physical and chemical parameters according to APHA, 1992 standard. The result of Analysis of Variance between values exhibited at the sampled points in Apomu and Ikire showed that there was no statistically significant difference in ground water pH values between the two communities in both wet (F = 0.102, P > 0.05) and dry (F = 0.471, P > 0.05) season. The result showed that the distance of the sample points to the dumpsite did not have a direct influence on water quality in that some parameters that were tested were found to exist more in the control samples than in the mean of the experimental samples. The results also showed that some of the tested parameters existed in higher quantities than both Nigerian and WHO standards for drinking water quality. The study concludes that the dumpsites in the study area has led to contamination of ground water as a result of leachate percolation from the dumpsites