Evaluating leachate contamination potential of landfill sites using leachate pollution index

The dumping of solid waste in uncontrolled landfills can cause significant impacts on the environment and human health. The principal concern is focussed on the pollution potential due to migration of the leachate generated from the landfill sites into the groundwater, the surface water or the sea. In this paper, the concept of the leachate pollution index, a tool for quantifying the leachate pollution potential of landfill sites, has been described and its practical application has been demonstrated by comparing the leachate contamination potential of two active and two closed landfills sites in Hong Kong. It has been found that the leachate generated from the closed landfills can have equal or more contamination potential in comparison to the active landfill sites and hence, the remediation actions and post-closure monitoring should be ensured at the closed landfills till the leachate generated is stabilized and poses no further threat to the environment.