Environmental Evaluation of Heavy Metal Contamination at Landfill Sites within the Prestea Huni Valley Municipal Assembly

Landfill sites serve as the primary destination for municipal solid waste in most developing nations; however, the waste streams deposited there vary widely, from non-toxic to highly hazardous. When landfills are not engineered or properly managed, they become significant sources of environmental contam ination through the leaching of heavy metals and the degradation of organic compounds. In the Prestea Huni Valley District Area (PHVDA), unengineered landfill sites pose a risk of severe pollution to adjacent soil systems. This study evaluated heavy metal contamination in nine soil samples collected from four municipal landfills located in Prestea, Aboso, Huni Valley, and Bogoso. Atomic Absorption Spectroscopy (AAS) was used to quantify soil heavy metal concen trations, while multivariate statistical analysis and standard pollution indices were employed to identify contaminant sources and assess environmental risks. The mean concentrations of heavy metals in the landfill soils decreased in the order of: Zn (1217.31 mg/kg) > Pb (534.63 mg/kg) > As (3.54 mg/kg) > Cd (0.83 mg/kg). According to hierarchical cluster analysis (HCA) and Pearson correlation coefficients, As and Cd are strongly correlated (r = 0.68) and share closely related geogenic and agricultural sources, whereas Pb and Zn are loaded independently, reflecting distinct anthropogenic pathways. The Potential Eco logical Risk Index (PERI) and Nemerov Pollution Index (NPI) indicated that the Aboso landfill soil is the most heavily contaminated with heavy metals, fol lowed by Prestea, Bogoso, and Huni Valley. The Aboso Landfill therefore ex hibited the highest overall pollution level and ecological risk. It is highly rec ommended that unengineered landfill sites that have been in use for over a decade, such as Aboso and Prestea, be systematically decommissioned and re mediated to safeguard human health and environmental integrity