Alliance Resource Partners, L.P. engages in the production and marketing of coal primarily to utilities and industrial users in the United States. It operates 10 underground mining complexes in the Illinois Basin, Central Appalachian, and Northern Appalachian regions. The company also leases land and operates a coal loading terminal on the Ohio River at Mt. Vernon, Indiana; and purchases and resells coal. As of December 31, 2011, it had approximately 911.4 million tons of proven and probable coal reserves. In addition, the company provides mine products and services comprising design and installation of underground mine hoists for transporting employees and materials in and out of mines; design of systems for automating and controlling various aspects of industrial and mining environments; and design and sale of mine safety equipment, including its miner, and equipment tracking and proximity detection systems. Further, it offers ash and scrubber sludge removal, coal yard maintenance, and arranging alternate transportation services. The company was founded in 1971 and is headquartered in Tulsa, Oklahoma.