ST. LOUIS (March 28, 2007) – Arch Coal, Inc. (NYSE:ACI) today announced that Mountain Coal Company's West Elk Mine earned two state awards for its outstanding efforts in environmental, health and safety practices in 2006.

The Colorado Division of Minerals and Geology (CDMG) and the Colorado Mining Association (CMA) presented West Elk with the awards at CMA's 109th National Western Mining Conference & Exhibition at the Grand Hyatt in Denver.

West Elk Mine was honored for excellence in land reclamation, including the use of existing ATV trails for sealing drainage wells to limit disturbance and the use of natural materials for erosion control on lands administered by the U.S. Forest Service. West Elk has operated for more than seven years without a state environmental violation.

West Elk also was recognized as a senior participant for its outstanding voluntary contributions to Colorado's Pollution Prevention Program, including the development of an outstanding employee health and safety plan for all employees, the conservation of water resources and the compacting of solid waste.

"We continually strive to be good neighbors while providing clean-burning, low-sulfur coal to electrify our 24/7 nation," said Arch Western Bituminous Group's President Gene DiClaudio. "The hard work put forth by the men and women of West Elk earned two significant awards. We appreciate the dedication these employees bring to safety and environmental stewardship in Colorado."

Mountain Coal Company's West Elk Mine is located in Somerset, Colo. Roughly 400 people are employed at West Elk.

St. Louis-based Arch Coal is one of the nation's largest and most efficient coal producers. The company's core business is providing U.S. power generators with clean-burning, low-sulfur coal for electric generation. Through its national network of mines, Arch supplies the fuel for approximately 6 percent of the electricity generated in the United States.