Mountaintop mining, often referred as mountaintop mining or valley fills, is a form of surface mining that involves an extreme topographic change to the summit or summit ridge of a mountain. It is most closely associated with coal mining in the Appalachian Mountains, located in the eastern United States. The process involves the removal up to 1,000 vertical feet of overburden to expose underlying coal seams. The overburden is often scraped into the adjacent drainage valleys in what is called a valley fill. Because of its destructive nature, Mountaintop mining is controversial and is protested by environmentalists, local residents, and others. Controversy over the practice stems from both the extreme topographical and ecological changes that the mining site undergoes, as well as from the storage of waste material generated from the mining and processing of the coal.