Capital Will Fund ADA Growth Opportunities and Enhance Environmental Performance of Coals Marketed by Arch LITTLETON, Colo., Mar 23, 2010 -- Arch Coal, Inc. (NYSE: ACI) ("Arch") and ADA-ES, Inc. (NASDAQ: ADES) ("ADA" or the "Company") today announced that Arch plans to invest $3.0 million in ADA to fund near-term growth opportunities. The first step of the investment was completed on March 23rd with the purchase of 143,885 shares of ADA for $1.0 million. The remaining $2.0 million is consideration for an exclusive license to use ADA's technology to provide environmental benefits for coals mined by Arch that are used to produce electricity. The license is currently being negotiated to define the royalty structure and is expected to be finalized in the next month.

Arch has been a significant shareholder of ADA since 2003 when the Company spun-out as a separate public entity.

Arch's President and Chief Operating Officer John Eaves, who has served on the ADA Board of Directors since 2004, commented, "As part of our commitment to clean energy, we are pleased to provide this additional investment in ADA, a leader in developing clean coal technology. We believe helping finance advanced technologies developed by ADA will enhance the environmental performance of our coals."

ADA has been successful at developing technologies that improve the performance of coals from Wyoming's Powder River Basin ("PRB"). In addition to flue gas conditioning chemicals used to aid in the collection of ash from PRB coals, the Company also developed a cost-effective brominated activated carbon technology that provides a means of achieving 90% removal of mercury emissions from PRB coals and CyClean technology, a proprietary coal additive that improves combustion of PRB coals in cyclone boilers resulting in enhanced efficiency and reduced emissions of mercury and nitrogen oxides. For the past several years, ADA has worked with Arch to explore certain unique characteristics of some of their coals that allow them to be burned with lower mercury emissions.

Mike Durham, ADA President and CEO, stated, "This investment will continue our long-standing relationship with Arch and allow the Company to fund opportunities that have the potential for significant near-term increases in revenues and earnings such as CyClean. As Congress is considering a year extension to the Section 45 tax credits, we want to be in a position to respond quickly to sell and install additional CyClean systems to produce refined coal."

About ADA-ES

ADA-ES is a leader in clean coal technology and the associated specialty chemicals. The Company develops and implements proprietary environmental technology and specialty chemicals that enable coal-fueled power plants to enhance existing air pollution control equipment, maximize capacity and improve operating efficiencies. ADA-ES supplies activated carbon ("AC") injection systems, mercury measurement instrumentation, and related services. Through Clean Coal Solutions, the Company provides its patented refined coal technology, CyClean, to utilities to enhance combustion of and reduce emissions from PRB coals in cyclone boilers, which qualifies for Section 45 tax credits. In addition, to meet the needs of the power industry for mercury control, a joint venture of the Company, ADA Carbon Solutions ("ADA-CS"), is developing state-of-the-art facilities to produce AC with the first plant projected to come on-line in 2010. The Company is also developing technologies for power plants to address issues related to the emissions of carbon dioxide.

About Arch Coal

St. Louis-based Arch Coal is the second largest U.S. coal producer, with revenues of $2.6 billion in 2009. Through its national network of mines, Arch supplies cleaner-burning, low-sulfur coal to U.S. power producers to fuel roughly eight percent of the nation's electricity. The company also ships coal to domestic and international steel manufacturers as well as international power producers.

This press release contains forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, which provides a "safe harbor" for such statements in certain circumstances.The forward-looking statements included in this release include statements regarding the finalization of a license agreement with Arch, impact of ADA's technologies on the performance of Arch's coal and timing of commencement of operations at ADA-CS's first AC plant.These statements are based on current expectations, estimates, projections, beliefs and assumptions of our management.Such statements involve significant risks and uncertainties.Actual events or results could differ materially from those discussed in the forward-looking statements as a result of various factors, including but not limited to ADA's inability to finalize negotiations with Arch on the license agreement and sign a definitive agreement with acceptable terms; changes in laws and regulations, prices, economic conditions and market demand; operational difficulties; impact of competition and litigation; availability of skilled personnel; and risks related to ADA-CS such as changes in the costs and timing of construction of the AC plant, failure to raise additional financing or satisfy conditions in existing agreements and actions of our joint venture partner.You are cautioned not to place undue reliance on our forward-looking statements.Our forward-looking statements are presented as of the date made, and we disclaim any duty to update such statements unless required by law to do so.