Geo Environmental Investigation of Abuad Dumpsite, Southwestern Nigeria

摘要

Geoenvironmental study of ABUAD female dumpsite was conducted to investigate the suitability of its location and potential impact on groundwater in the environment. Profiling and Vertical electrical sounding methods were employed using Dipole - Dipole and Schlumberger configuration respectively. Five points were sounded and one profile was occupied. Three heterogeneous subsurface lithologic units were established namely; lateritic topsoil, clayey-sand, and, fresh basement. The curve types are simple H and HA. The topsoil and clayey-sand materials are characterized with relatively low resistivity values while the fresh basement materials are characterized with high resistivity values. The average resistivity and thickness values for the topsoil are 280.0Ωm and.2.3m respectively. Clayey-sand was encountered in all the locations with average resistivity and thickness values of 32.0Ωm and 7.3m respectively. Basement is relatively shallow in the study area, it was encountered in all the locations with an average resistivity and depth values to the top of basement of 674Ωm, and 9.6m respectively. Overburden materials are relatively thin within the area with an average resistivity and thickness values of 156Ωm, and 9.6m respectively. The overburden materials constituting the aquiferous units within the study area are porous, vulnerable, and good paths for leachate migration. The relatively low resistivity values within the clayey-sand layers (14 - 61Ωm) are suggestive of leachate intrusion, while relatively high resistivity values of the impervious basement are due to their crystalline nature. The proximity of the dumpsite to both the cafeteria and residential halls is a cause for concern.