The mine was started by
Cyrus Wilberg in September 1949. In October 1968, the mining rights were bought by
Peabody Coal Company, who idled the mine except for limited exploratory mining until March 1974, when energy prices saw a sharp rise. Utah Power & Light (UP&L) (now operated as Rocky Mountain Power a division of
PacifiCorp) purchased the rights to the mine on April 18, 1977, and then contracted out operating the mine to
American Coal Company. In June 1979 Emery Mining Corporation (EMC) took over operations. In December 1984 the mine employed 326 miners, and 290 of those were working underground on three shifts-a-day, five days a week. Production averaged 11,000 tons of coal per day. After the fire, in 1985, the mine was divided into two separate mines. The mine workings on the west side of the fire seals became the Cottonwood Mine (MSHA ID No. 42-01944). UP&L took over operating the mine, forming UP&L Mining Division, on April 29, 1986, retaining most of the EMC employees. Composer and conductor
Mack Wilberg is the son of a former part-owner of the mine. ==1984 disaster==