The Office of Surface Mining Reclamation and Enforcement (OSM or OSMRE) is a branch of the United States Department of the Interior. It is the federal agency entrusted with the implementation and enforcement of the Surface Mining Control and Reclamation Act of 1977 (SMCRA), which attached a per-ton fee to all extracted coal in order to fund an interest-accruing trust to be used for reclamation of abandoned mine lands, as well as established a set environmental standards that mines must follow while operating, and achieve when reclaiming mined land, in order to minimize environmental impact. OSM has about 500 employees, who work in either the national office in Washington, DC or of the many regional and field offices(OSM's Three Regions].