Investigation of heavy metals pollution in Piyungan Landfill underground and surface water

Assessing the potential hazard to the groundwater resource and surface runoff from solid waste disposal activities is considered necessary. This study focused on the effect of the leachate produced from the Piyungan landfill to both groundwater resources and surface runoff water quality. Groundwater samples were taken from point W1 (control) and W26, leachate samples were taken from LP1 (before treatment) and LP5 (after treatment), and drain samples were taken from L6 and L14, respectively. Heavy metals in these samples were analyzed using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). The results showed that leachate and drain samples had higher heavy metals content compared to groundwater samples. Leachate migration might happen in W26 since it located in the lower elevation of the landfill. For the leachate sample, the concentrations of Cr, Mn, Ni, As, and Se exceeded the allowable limit for raw water and leachate effluent. Deposition of heavy metals (Cr, Mn, Ni, As and Se) were also detected in W1 and W26 but still within the permissible limit. Continuous monitoring for heavy metals migration and the addition of leachate treatment processes in the landfill are suggested to avoid the occurrence of risky pollution to the surrounding area.