Cordero Rojo Mine

Located 24 miles southeast of Gillette, Wyoming, Cordero Rojo Mine is in the southern portion of the Powder River Basin. In 1993 Rio Tinto Energy America (RTEA) acquired the Cordero Mine from the Sun Oil Company. RTEA then purchased the adjacent Caballo Rojo Mine from the Marigold Land Company, a subsidiary of Drummond Company, Inc. in 1997. RTEA subsequently merged the two facilities operationally and those synergies continue today under Cloud Peak Energy.

Cordero Rojo mines the Wyodak seam, the principal economic coal seam in the Wyoming portion of the Powder River Basin. The average seam thickness is between 55 to 70 feet. The typical average heating quality of the subbituminous coal is 8,400 Btu.

Cordero Rojo Mine utilizes a highly efficient combination of dragline open-pit operations with truck-shovel assist to produce significant volumes of coal each year. In 2009, Cordero Rojo mined and shipped more than 39.3 million tons of coal.

Cordero Rojo is permitted to mine 65 million tons of coal per year. Cordero Rojo sells its coal primarily to electric utilities in the southern and western United States.

The Cordero Rojo Mine workforce total was 585 employees at year-end 2009. Cordero Rojo has won the Sentinels of Safety Award five times. The Sentinels of Safety is an award given by the U.S. Department of Labor. This award recognizes the surface coal mine in the United States with the best safety performance for the year.

From 1996 to 2006 Cordero Rojo was recognized four times by state agencies for accomplishments in reclamation and wildlife habitat development.

Environmental Awards

2006	Excellence in Surface Coal Mining and Reclamation Award, from the Wyoming Department of Environmental Quality for designed riverbed reconstruction
1999	Excellence in Surface Coal Mining and Reclamation Award from the Wyoming Department of Environmental Quality - Land Quality Division for construction of reclaimed area wetlands
1998	Wildlife Habitat Reclamation and Stewardship Award from the Wyoming Game and Fish Department for accomplishments in establishing wetlands using detention dikes and pit pumpage water
1996	Excellence in Surface Coal Mining Permitting, Honorable Mention; from the Wyoming Department of Environmental Quality - Land Quality Division permitting efforts on the Belle Fourche River diversion

Safety Awards

2007	Wyoming Mining Association Safety Idea Winner for the development of a crane and rigging safety standard
2007	OJ Laughlin Sportsman Award from Elko Mine Rescue Competition
1999	Sentinels of Safety Award, Large Surface Coal Mine, by the U.S. Department of Labor
1999	Safest Surface Coal Mine from the Office of the State Mine Inspector
1998	Sentinels of Safety Award, Large Surface Coal Mine, by the U.S. Department of Labor