Formulation and Demonstration of a Technique to Quantify Leachate Pollution Potential of Municipal Landfills

Landfilling is one of the most widely used techniques, despite its numerous environmental problems, for the treatment and disposal of solid wastes. Significant effort has been directed toward the development of improved landfill designs to reduce the negative environmental impacts. Still, at present, about three quarters of the countries and territories around the world use 'open dumping' method of disposal of municipal solid waste. Municipal solid waste landfills, either closed or active, pose threat to human health and the environment. The greatest concern is the potential of leachate from a landfill to pollute the valuable ground water or surface water supplies. Due to a large number of closed and active landfills in every country and the limited resources, decisions regarding landfill remediation have to be based on the comparative evaluation of leachate contamination potential of landfills on a case-by-case basis. An index for easy comparison of leachate contamination potential of different landfills in a given geographical area would be a useful tool in this regard. With this objective in view, a technique has been formulated to quantify the leachate pollution potential of landfills on a comparative scale using an index. The index termed as `Leachate Pollution Index' has been formulated based on the Delphi Technique. In-depth review of the existing environmental indices was performed to adopt an appropriate methodology for formulating the Leachate Pollution Index. A panel of experts from various professions with knowledge in environmental engineering and solid waste management was prepared. For formulating the index, eighteen leachate characteristics viz., Total Chromium, Lead, COD, Mercury, BOD5, Arsenic, Cyanide,