Environmental groupshave filed a lawsuit intended to force the federal government into finalizing rules governing the disposal of coal ash.Coal ash is the byproduct of burning coal for electricity, and it is stored at both the Cane Run and Mill Creek power plants in Jefferson County. It’s regulated at a state level, but there aren’t any uniform federal regulations for the ash.The lawsuit was filed in U.S. District Court yesterday. Jennifer Peterson of the Environmental Integrity Project says ponds and landfills that store coal ash across the country are contaminating air and water. She says federal regulation of the material is long overdue.“The delay has been long enough so we are heading to court to seek an order from the court that would require EPA to complete the review and revise the regulations as soon as possible,” she said.The Environmental Protection Agency announced two ways it was considering handling coal ash in 2010, but they haven’t yet announced plans to finalize the rules. One of the options they’re considering would treat the ash like a hazardous waste—this plan is supported by environmental groups. The other would treat ash as a special waste, which is the approach power plants favor.Now, environmental groups say they want the EPA to finalize the rules, whichever version they end up choosing. Peterson says the amount of coal ash stored in landfills and ponds nationwide is increasing.“It really is long past the time for action and while EPA is dragging its feet, the problem keeps getting bigger,” she said.The groups point to evidence of water contamination from coal ash ponds and landfills. In Louisville, the neighbors of both power plants have also complained about air pollution and dust.The lawsuit requires the EPA to respond within 60 days.