Operational for more than 30 years, Black Butte Coal Company is one of the largest permitted surface coal mines in the United States. Spread on more than 70-square-miles of land, Black Butte is managed by Kiewit Mining Group. The mine produces a wide variety of coal, including Fort Union, Lance and Almond geologic formations. A subsidiary of Kiewit Corporation, Kiewit Mining Group utilizes mine designs developed with state-of-the-art software, and manages the operation of dozers, trucks and shovels. Kiewit has more than 30 district and area offices in the United States and Canada. Headquartered in Point Of Rocks, Wyo., the company employs more than 10,000 craft workers, registered engineers, managers, and administrative and support staff. Additionally, it offers expertise in the areas of transportation, power, water resources, construction, oil and gas, defense, mining, telecommunications, electrical, marine, and underground projects.