Leachate is a liquid that forms when water filters through waste materials in landfills. As it moves, the water dissolves various substances, including organic and inorganic compounds, which can be harmful to the environment. Proper management of leachate is crucial to prevent contamination of soil and groundwater. To control leachate, landfills are designed with systems that collect and treat this liquid before it can escape into the surrounding area. This treatment process helps to reduce the environmental impact of landfills and ensures that harmful substances do not enter ecosystems or drinking water supplies.