Twelve states have joined a lawsuit defending a new rule from the Environmental Protection Agency that will limit mercury and other toxic air emissions. But Kentucky is not among those joining the suit.The EPA’s rule was finalized in February. Almost immediately, the National Mining Association challenged the rule in the D.C. Court of Appeals.In the past week, twelve states, the District of Columbia and New York City have filed to intervene in the case. They join several environmental groups in defending the EPA’s ruling.Mercury is emitted from coal-fired power plants, so not surprisingly, none of the country’s major coal producers—including Kentucky—are among the intervening states. But Illinois Attorney General Lisa Madigan is, despite the fact that her state produced about 33,000 tons of coal last year.Spokesman Scott Mulford says the rules are important to air quality, and it’s imperative that they be enforced.“Yes, coal has been and will continue to be an important industry in the state of Illinois,” he said. “And it’s many peoples’ opinion that there’s a way to do it and co-exist with the power industry.”A spokeswoman for Kentucky Attorney General Jack Conway says Conway doesn’t plan on intervening in this case.