Heavy Metal Pollution in Landfill Environment: A Malaysian Case Study

Heavy metal contamination of soil is of major concern from an ecological point of view. This study aims to characterize soil samples from different sites of two waste disposal grounds in Malaysia, to study heavy metal contamination in the landfill environment. The soil samples were obtained at different depths from 2m to 35m deep to find the possibility of heavy metal migration from the waste cell into the deeper layers. Results from the analysis of samples from Panchang Bedena landfill indicated that all heavy metals analyzed were below the Dutch Intervention Standard for Soil Remediation. Pb was at its highest concentration at the upper layer than the lower layer; displaying a decreasing trend at the deeper soil. On the other hand, Fe and Zn depicted increasing trend where the highest concentration was at the deepest soil samples, while the lowest concentration was at the surface soil. Though the heavy metal contamination level was below the serious risk to human exposure, precautionary actions need to be implemented since higher volume of waste disposal in future might cause to alter the intensity of these heavy metal in the landfill soil. The other study area at Kelana Jaya indicated an opposite results. The surrounding soil of the Kelana Jaya ex-disposal site was heavily contaminated with metal elements which exceeded the Dutch Intervention Value. Among the elements at the highest value were arsenic (64.4 mg/kg) and mercury (11.5 mg/kg). This warrants proper remediation or precautionary measure in order to prevent risks to human and the environment.