Impact of landfill leachate on the groundwater quality in three cities of North India and health risk assessment

Landfill leachate has an adverse impact on groundwater quality as well as on living being. It contain high levels of organic, inorganic, heavy metal, and xenobiotics, which percolates through the subsoil and contaminate the groundwater. To assess the effect of landfills on groundwater, various physicochemical parameters including heavy metals, and microbiological examination of leachate and groundwater samples was conducted. The results obtained were compared with Bureau of India Standards and World Health Organization guidelines. The results of the study shows that the majority of the sample do not lie in the permissible limits. According to the results, the concenteration of ammoniacal nitrogen (9.8 mg/L), chemical oxygen demand (128 mg/L), chloride (115 mg/L), sodium (98 mg/L) and potassium (42.2 mg/L) was found relatively higher in water samples that have lower depth (30 ft) and distance (1 km) from the landfill. The concentration of measured parameters decreases with increase in depth and distance confirming that the leachate is the potential source of groundwater contamination. Hazard index of Chandigarh, Mohali, and Panchkula landfill site was 0.61, 0.53, and 0.01 mg/kg/day in pre-monsoon and 0.38, 0.24, and 0.01 mg/kg/day in post-monsoon indicating non-carcinogenic health risks.