ST. LOUIS (November 21, 2005) - Business Week magazine named Arch Coal, Inc. (NYSE:ACI) to this year's Web Smart 50 list as a management pacesetter.

"The Web Smart 50 highlights the quiet innovation going on inside organizations," said the article in the November 21 issue of Business Week. "These companies are profoundly altering the business landscape."

Arch Coal was recognized as a Web Smart 50 company for employing the latest technology to streamline its largest coal mining operation, Black Thunder. Arch Coal installed MineStar, a central dispatching system that relies on a global positioning system (GPS) to track and monitor the location of major mining equipment. Using an IP-based network, the computer dispatcher can optimize equipment utilization by rerouting trucks before bottlenecks occur.

By harnessing technology, Black Thunder saw a 10% efficiency improvement and also eliminated the need to acquire three 300-ton trucks for Black Thunder's fleet. The result was an expense savings of roughly $3.6 million annually, as well as the deferral of $9 million in capital spending.

Earlier this year, Arch Coal earned the CIO 100 award for improving efficiencies and adding shareholder value through the resourceful use of information technologies.

St. Louis-based Arch Coal is the nation's second largest coal producer and mines low-sulfur coal exclusively. Through its subsidiary operations in West Virginia, Kentucky, Virginia, Wyoming, Colorado and Utah, Arch provides the fuel for approximately 7 percent of the electricity generated in the United States.