Black Thunder Coal Mine

A bucket that can hold 170 cubic yards of material while unearthing rock down to a coal seam.  Arch Coal company employs over 500 workers at Black Thunder, which for many years was the nation's single largest coal mine in Wyoming's Powder River Basin...Black Thunder works coal reserves with five draglines in the 70 foot Wyodak seam producing more than 65 million tons of coal annually on federal land. The low-sulphur, sub-bituminous coal is suitable for power station fuel without any preparation except crushing.  ..Black Thunder produces more than two tons of coal per second, 24 hours a day, 365 days a year. The mine surpassed a 750 million ton shipment milestone 25 years after opening in 1977.