A widely used method of garbage disposal that consists of dumping garbage on waste land, such as a quarry, open-cast mine, or swamp. Ideally, this is evenly spread, compacted, and covered with a layer of soil After decomposition and settling, which takes several years, the site can be beautified with playing fields or, if local zoning laws permit, converted for commercial or even residential use. Decomposing organic matter in landfill sites generates methane, and monitoring for methane concentration should be obligatory, but seldom is. Sometimes methane is harvested and used as fuel. Noxious odors and toxic fumes are a hazard of many landfill sites. Other hazards include toxic material in garbage that can leach into aquifers; proliferation of pests such as rats; and ecosystem disruption if the landfill was formerly a stage on the flight path of migratory birds or habitat for endangered species. Landfill sites in many jurisdictions are subject to increasingly strict regulation, with innovations such as separation of garbage into recyclable and other categories and safeguards to protect sensitive ecosystems and minimize harm to the environment. In many low-income countries, human scavengers risk their health to collect whatever they can salvage for reuse or sale. See also hazardous waste disposal.
Subjects: Science and Mathematics — Public Health and Epidemiology.