Leachate is the residual liquid produced by the percolation of water and liquids through a zone containing stored waste, chemical products or, simply, soil contaminated by pollutants.
Leachate and the environment
Leachate, a product of the dissolution of organic matter and trace elements (heavy metals, organic and chemical pollutants, radionuclides...) is a source of soil and water pollution, including underground pollution.
Monitoring, collection and remediation measures must be used to address leachate. Sealing systems reduce the risks of leaching and the quantities of leachate, while a drainage network collects liquids produced from the percolation process. Leachate is then recycled (composting) or re-treated, locally or in a treatment plant.
A drain for collecting leachate in the La Roque waste deposit centre, near Nice, France. © nonaladechargedelaroque CC by 2.0