Alliance Resource Partners, L.P. (ARLP) operates as a diversified natural resource enterprise, with a primary focus on extracting and supplying coal to utility companies and industrial customers across the United States. The company's business activities are categorized into four main segments: Illinois Basin Coal Operations, Appalachia Coal Operations, Oil & Gas Royalties, and Coal Royalties. ARLP's coal production encompasses a variety of thermal and metallurgical grades, each with distinct sulfur and heat content characteristics. The firm manages seven underground mining complexes situated across six states: Illinois, Indiana, Kentucky, Maryland, Pennsylvania, and West Virginia. In addition to its mining operations, ARLP leases land, manages a coal loading facility on the Ohio River at Mt. Vernon, Indiana, and engages in the buying and reselling of coal. Further diversifying its portfolio, the company holds mineral and royalty stakes in approximately 1.5 million gross acres of land within key oil and gas producing regions, prominently the Permian, Anadarko, and Williston Basins. Beyond its core resource activities, ARLP also offers an array of mining technology solutions, including data network and communication systems, personnel tracking, proximity detection, industrial collision avoidance, and specialized data and analytics software. As of December 31, 2021, the company's substantial coal reserves included an estimated 547.1 million tons of proven and probable mineral reserves, complemented by 1.17 billion tons of measured, indicated, and inferred coal resources, all located within its operational states of Illinois, Indiana, Kentucky, Maryland, Pennsylvania, and West Virginia. Founded in 1971, Alliance Resource Partners, L.P. is headquartered in Tulsa, Oklahoma.