Impact of Leachate on Permeability Characteristic of Soil around Lapite Dumpsite in Ibadan, Southwestern Nigeria

This study examined the impact of leachate from Lapite dumpsite in Ibadan, Oyo State, Southwestern Nigeria on the permeability coefficient of the soil around the site. Soil samples were taken from upslope and downslope sections of the dumpsite and the geotechnical properties of the samples collected (disturbed and undisturbed) were analyzed at the University of Ibadan, Ibadan and Obafemi Awolowo University soil laboratories. Geotechnical tests conducted include particle size distribution, Atterberg limits, specific gravity and permeability coefficient. The coefficient obtained has higher values which may be as a result of effect of leachate or soil formation of the region. The permeability coefficients of the soil at the downslope section of the dumpsite were found to be higher than those at the upslope section.
This shows that leachate has more effect or has travelled faster to downslope section than to the upslope section. Topography might have contributed to this. It is recommended that donor agencies/government should endeavour to convert the dumpsite to a landfill because permeability coefficient of the area is the type that encourages fast flow of leachate out of the dumpsite. This will save the natural resources (soil/groundwater) around the site from contamination