Arch Coal Invests $1.3 Million in ADA-ES Including $1.0 Million for Common Stock at $7.26 Per Share.

Business Editors

LITTLETON, Colo.--(BUSINESS WIRE)--Oct. 7, 2003

ADA-ES, Inc. (OTCBB:ADES), today announced that Arch Coal, Inc. (NYSE:ACI) has invested $1.3 million in ADA-ES. The second largest coal producer in the U.S., Arch Coal is a joint venture partner of ADA-ES and has provided financial support to ADA-ES on several mercury control programs.

Pursuant to the investment agreement, Arch purchased (1) a $300,000 convertible debenture from the Company, (2) $1.0 million of common stock at $7.26 per share, and (3) options to purchase 50,000 additional shares of common stock. $300,000 of the proceeds from the Arch investment was used to reduce indebtedness of Earth Sciences, which was assumed by ADA-ES upon completion of ADA-ES' spin-off from Earth Sciences. As of September 30, there were approximately 3.6 million shares of ADA-ES outstanding, including the shares issued to Arch.

Dr. Michael Durham, President of ADA-ES, stated, "We believe Arch's investment in ADA-ES is a testament to our reputation in the mercury emission control industry. Through our joint venture with Arch, we package our ADA-249 chemical with Arch's Powder River Basin "PRB" coal to enable cyclone-fired power plants to burn the less expensive PRB coal, enhance operational flexibility and improve the marketability of combustion by-products, without increasing emissions or making a significant capital investment. We are enthusiastic about developing our relationship with Arch."

John W. Eaves, Arch Coal's Executive Vice President and Chief Operating Officer, commented, "We are pleased to complete our investment in ADA-ES and further align our interests. The advantages that exist when coal is used as a source of electricity, including lower energy costs, greater energy independence, and increased competitiveness in the global arena, have created a need for emission control technologies. ADA-ES has developed a cost-effective and innovative technology to capitalize on the opportunity. As a joint venture partner and investor in ADA-ES, we look forward to continuing our mutually successful partnership."

Coal is the source of approximately 50% of the electricity that Americans use each day. ADA-ES is committed to helping maintain the key role of coal in U.S. power generation by increasing the effectiveness and reducing costs of emission control technology. All of the Company's products have been developed to help achieve this goal. ADA-ES works closely with the coal industry and has been active in the National Coal Council, American Coal Council (and its predecessor the Western Coal Council) and the National Coal Transportation Association.

Quotation of the ADA-ES stock on the OTCBB, under the assigned ticker symbol of ADES, is expected to commence in the near future once NASD completes its review.

About Arch Coal

Arch Coal (NYSE: ACI) 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 6 percent of the electricity generated in the United States. In 2002, Arch Coal's revenues totaled $1.5 billion.

About ADA-ES

Headquartered in Littleton, Colorado, ADA-ES, Inc. develops and implements proprietary environmental technology and specialty chemicals that mitigate the environmental impact from electric power and industrial companies while reducing operating costs.

This press release may contain forward-looking information within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. The United States Private Securities Litigation Reform Act of 1995 provides a "safe harbor" for such forward-looking statements in this document that are based on information the Company believes reasonable, but such projections and statements involve significant uncertainties. Actual events or results - including predicted revenues and achievement of positive cash flow -- could differ materially from those discussed in the forward-looking statements as a result of various factors including but not limited to changing market demand for ADA-ES chemicals and systems and changes in technology, laws or regulations, demand for the company's securities, and other factors discussed in the company's filing with the U.S. Securities and Exchange Commission.