Case Studies in Chemical and Environmental Engineering (Dec 2023)
Evaluation of Groundwater contamination and the Health Risk Due to Landfills using integrated geophysical methods and Physiochemical Water Analysis
Abstract
The wobbly state of waste management (WM) and the high level of environmental irresponsibility pose a significant threat to environmental health, which invariably endangers public health, regional groundwater systems and atmospheric conditions. These unruly human factors have compelled this study to apply integrated geophysical methods, physiochemical water analysis, diagnostic survey questionnaires (DSQs) and reconnaissance surveys (RSs) to assess the environmental impacts and the possible public health risks of poor WM in Northern Nigeria. Geophysical investigation delineated leachate plume accumulated zones as conductive regions, which were captured within the depth of 0–10.5 m with low resistivity contrast relatively below 9.0 Ωm. The resistivity data of the overburden topsoil overlying the regional aquifer vary between 3.7 Ωm and 23 Ωm within the dumpsites and 111 Ωm – 413 Ωm off-dumpsites. The investigation was extended to 20 m–55 m off-dumpsites to monitor the impacts of landfills on the ambient environment. The resistivity data shows that the landfill leachate plumes have compromised the integrity of the regional subsoil, which invariably questions the purity of the groundwater. The physiochemical data depicts high content of BOD (79 – 811) mg/l, COD (99 – 1997) mg/l, TDS (511 – 2117) mg/l, while the level of the heavy metals (HMs) content across the three water sources vary significantly with Fe (0.210 – 2.997) mg/l, Pb (0.028 – 2.121) mg/l, Cr (0.029 – 1.413) mg/l, Cd (0.021 – 0.722) mg/l. The high content of organic substances and HMs present in the sample water may have altered the chemistry of the regional surface and groundwater, which are detrimental to human health. The comparative evaluation of the regional groundwater susceptibilities to the surface contaminants emerging from dumpsites/landfills in various geological locations shows that the landfill leachate plumes may be responsible for the regional groundwater pollution encountered in the water sample. The HMs-dominated leachate plumes penetrating the subsoil seem to have significantly influenced the electrical resistivity values of the landfill subsurface stratiform. A Strong media investment to enlighten the people is critical in going forward. This article will aid stakeholders in making strategic decisions to minimize the adverse effects of uncontrolled landfills.
