HELPER, Utah, June 28, 2010  -- Arch Coal, Inc. (NYSE: ACI) today announced that Skyline mine has earned top honors for underground mine safety among an eight-state region for a fourth consecutive year.

The Rocky Mountain Coal Mining Institute (RMCMI) today awarded the employees of Skyline mine with the 2010 Safety Award for underground mines due to an outstanding and ongoing safety performance achieved during calendar year 2009.

"This ongoing safety performance is proof positive of the dedication of the men and women of Skyline," said John W. Eaves, Arch's president and chief operating officer. "Day in and day out they live by their safety values and for this they can be very proud."

Canyon Fuel Company is a wholly owned subsidiary of Arch Coal, Inc. Canyon Fuel's Skyline mine is located near Helper, Utah, and employs about 215 people. Skyline sold a total of 10 million tons of coal during the four-year period from 2006 to 2009.

St. Louis-based Arch Coal is the nation's second largest coal producer. The company's core business is providing U.S. power generators with cleaner-burning, low-sulfur coal for electric generation. Through its national network of mines, Arch supplies the fuel for approximately 8 percent of the electricity generated in the United States. A list of safety and environmental awards is available at http://www.archcoal.com/aboutus/awards.aspx.