Effect of Open Dumping of Municipal Solid Waste on Groundwater Quality in Ekurede Itsekiri, Warri South LGA, Delta State, Nigeria.

Abstract

Generation of municipal solid waste is on the increase because of economic development and increased population. Due to lack of finance which result to improper waste management practices in most developing countries like Nigeria, solid wastes are being dumped on land without adopting any acceptable sanitary land filling practices and this pose a threat to the populace and the surrounding environment as it causes all types of pollution including groundwater pollution. Hence there is need to regularly monitor the groundwater around such site to ascertain its portability for human consumption. In this study, groundwater samples were collected from ten different boreholes at distances from a dump site in Ekurede Itsekiri community. Leachate samples were also collected randomly from five different leachate points around the same dump site. These samples were collected in May, 2021 (rainy season). Both the groundwater and leachate samples were analysed for their physiochemical properties and then evaluated for their heavy metal pollution (HPI) status. The physiochemical analysis of the groundwater revealed that of all the parameters examined, pH, TDS, NH4N and Fe were not within acceptable limits and for the leachate, pH, coliform bacteria, Fe, Cr, Cd and Pb were not within acceptable limits. This is implying that the dump site has impact on the groundwater quality around it. All parameters analysed were detected in the leachate while some parameters (coliform bacteria, Turbidity, TSS, Cr, Cd, Ni and Pb) were not detected in the groundwater. The clayey soil in the study area seems to have significantly influenced the absence of these contaminants from the groundwater. The HPI shows that the groundwater and the leachate are not critically polluted with heavy metals as the mean HPI values for the groundwater (35.977) and the leachate (34.85) were below the critical index value (100). Although, the HPI has indicated that the groundwater is not critically polluted with heavy metals, but results of the physiochemical analysis has revealed that the groundwater around the dump site has deteriorated and as such it is unsafe and unfit for human use.