method of controlled disposal of refuse on land. The method was introduced in England in 1912 (where it is called controlled tipping) and involves natural fermentation brought about by microorganisms. Usually the refuse is deposited in shallow layers, compacted, and covered within 24 hours with earth or other chemically inert material to form an effective seal. Mechanical equipment such as a bulldozer is used to grade, compact, and cover the refuse. The method often is employed to reclaim otherwise useless land, i.e., to fill declivities to levels convenient for building or park and other public purposes.