Impact of Arak landfill leachate on groundwater quality in terms of heavy metals in Amanabad Arak plain

Heavy metals (Mercury, Arsenic, Lead, Zinc, Copper, Nickel, and Cobalt) of groundwater in Amanabad plain on the 12 drinking wells were compared in the years of 1997 and 2016 downstream of Arak Landfill. A comparison of heavy metal concentrations of wells with drinking standards indicates that water is not contaminated with Mercury, Zinc, Copper, Nickel, and Cobalt in the two years. The waters showed contamination with Arsenic in 2016 and Pb in 1997 and 2016 respectively. The index of Arsenic and Lead metal contamination in wells in 2016 was more than ten times that of 1997. Fifty-eight percent of drinking water wells, which had a moderate level of pollution in the 1997 year, but, were high polluted in the 2016 year. Examination of Arsenic and Lead concentrations in leachate and soil of Arak landfill showed that they are more than 50 times the standard water and even drinking water of Amanabad plain. The study showed that Arsenic and Lead in the wells of the area were caused by landfill leachate. Lead has also been derived from atmospheric dust in nearby industries and traffic in the area. Therefore, measures should be taken to reduce Arsenic and Lead in the Arak municipal solid waste landfill as well as industries and urban transport.