HELPER, Utah (June 29, 2009) - 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 third consecutive year.

The Rocky Mountain Coal Mining Institute (RMCMI) awarded the employees of Skyline mine with the 2009 Safety Award for underground mines due to an outstanding and ongoing safety performance during calendar years 2006, 2007 and 2008.

"I want to commend the people of Skyline for focusing on best-in-class safety year after year," said John W. Eaves, Arch's president and chief operating officer.

"Congratulations to all the employees at Canyon Fuel Company's Skyline mine on winning the award for the third straight year," said Ed Pettigrew, chairman of the RMCMI safety committee. "Skyline's total incident rate of 0.82 [per 200,000 employee-hours worked in 2008] again puts you at the head of the pack that is increasingly getting better each year. Your continued safety performance is truly remarkable and deserves this recognition."

Canyon Fuel Company is a wholly owned subsidiary of Arch Coal, Inc. Canyon Fuel's Skyline mine is located near Helper, Utah, and employs more than 175 people. Skyline sold a total of 7.2 million tons of coal during the three-year period from 2006 to 2008. Additionally, Skyline mine earned the 2005 Sentinels of Safety award from the U.S. Department of the Interior for completing more than 28 months and 500,000 employee-hours without a single reportable or lost-time injury.

St. Louis-based Arch Coal is one of the nation's largest coal producers, with revenues of $3.0 billion in 2008. 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. A list of safety and environmental awards is available at http://www.archcoal.com/aboutus/awards.aspx.