Arch Coal, Inc. engages in the production and distribution of thermal coal. It operates through the following segments: Powder River Basin, Metallurgical and Other Thermal. The Powder River Basin segment contains thermal operations in Wyoming. The Metallurgical segment contains metallurgical operations in West Virginia. The Other Thermal segment contains supplementary thermal operations in Colorado, Illinois and the Coal Mac thermal operations in West Virginia. The company was founded in 1969 and is headquartered in St. Louis, MO.