A group of 12 states and a coal mining company have filed separate lawsuits in the U.S. Court of Appeals for the District of Columbia in an effort to stop the Environmental Protection Agency (EPA) from regulating CO2 emissions from existing coal-fired power plants.

The states—Alabama, Indiana, Kansas, Kentucky, Louisiana, Nebraska, Ohio, Oklahoma, South Carolina, South Dakota, West Virginia, and Wyoming—all rely, at least to some extent, on the coal industry to help support their economies.

The lawsuit filed by the states challenges the settlement agreement the EPA entered into in 2011, under which the agency promised to regulate CO2 emissions from existing coal-fired power plants under Section 111(d) of the Clean Air Act (CAA). On June 2, the EPA released its “Clean Power Plan,” which followed through on that commitment.

The lawsuit contends that the agreement is illegal because the EPA already regulates coal-fired power plants under section 112 of the CAA—the hazardous air pollutants program—and the law expressly prohibits double regulation of such plants.

“This lawsuit represents another effort by our office to invalidate the EPA’s proposed rule that will have devastating effects on West Virginia’s jobs and its economy,” West Virginia Attorney General Patrick Morrisey said.

The states are not the only ones fighting to stop the EPA rule. Murray Energy Corp.— the largest privately owned coal company in the U.S.—filed a lawsuit against the EPA on June 18 “challenging the EPA’s promulgation of illegal, irrational, and destructive cap-and-tax regulations for existing coal-fired power plants.” The company produces approximately 65 million tons of bituminous coal each year and would be hit financially if the EPA regulation forces a reduction in coal usage.

“The plain language of the Clean Air Act clearly prohibits the EPA from promulgation of these unlawful and very damaging rules,” said Gary M. Broadbent, assistant general counsel and media director for Murray Energy.

Another coal mining company isn’t waiting to see how the lawsuits play out. Alpha Natural Resources Inc. announced on July 31 that it has given notice to approximately 1,100 employees advising them of the expected idling of 11 of its surface mines in West Virginia based on market conditions. The company said that the actions are being triggered by, among other things, “government regulations that are causing electric utilities to close coal-fired power plants and forego construction.” The workforce reductions are expected to take place by mid-October.

For more carbon rule coverage, see “EPA Public Hearing on Carbon Pollution Standards Draws More ‘Public’ than Power Industry Speakers,” “FERC Commissioners, Other Experts Testify on Carbon Rule Reliability and Financial Impacts,” and “McCarthy Fields Carbon Rule Concerns on Coal, Costs, Climate Change.”

Aaron Larson, associate editor (@AaronL_Power, @POWERmagazine)