Impact of Landfill Leachate on Ground Water Quality: A Review

The most widely utilized method of solid waste disposal around the world is the use of Municipal Solid waste (MSW) landfills. Upto 95% of the waste collected worldwide is disposed off in landfills. The main issues related with the landfills are the production of methane gas and liquid leachate. Among these issues, generation of leachate is of growing concern. In developing countries landfilling is the commonly used method and most of the landfills do not have any liners at the base or proper top covers, which as a result of leachate generation from solid waste results in the potential problems of ground water/surface water contamination. Besides landfilling is considered the most economical method of waste disposal, in recent decades several problems of social and environmental attention are associated with landfills. Amongst the environmental problems related to MSW landfilling, ground water contamination is the most prominent. From physical, chemical, and biological point of view the leachate generated from MSW disposal sites is considered as one of the highly contaminated resources. Sanitary landfill that is present in urban areas is often related to potential environmental pollution of ground water and surface water. Landfills pose potential risk to human health as well due to the toxic impacts caused by the leachates when released into the environment and the potential of landfills to generate leachates even after 100 years of closure. It has been reported earlier that even small amounts of leachate can pollute large volume of groundwater that can make them unusable for domestic and many other purposes. In this chapter authors have reviewed the leachate composition from MSW landfills, contamination of ground and surface water sources by different pollutants present in the leachates. The effect of depth of water source and its distance from landfill along with other factors affecting the contamination of water sources is also reviewed. Authors have suggested remedial measures and that proper management of solid waste can help to decrease the contamination of through leachate production.