Today the U.S. Department of Justice (DOJ) filed an enforcement action in federal district court against Luminant Generating Company, a subsidiary of Dallas-based Energy Future Holdings, for violations of the Clean Air Act. The DOJ filed the case against Luminant on behalf of the U.S. Environmental Protection Agency (EPA), which first issued a Notice of Violation to Luminant in July 2012. According to EPA, Luminant made unauthorized changes to the Big Brown coal-fired power plant in Freestone County and the Martin Lake coal-fired power plant in Rusk County without properly controlling sulfur dioxide and nitrogen oxide emissions. The case filed today under seal follows up on EPA’s Notice of Violation and is the next step in ensuring that Luminant comes into compliance with the Clean Air Act.

“Today’s action by the Department of Justice is reassurance that public health protections are finally coming to many Texas communities,” said Charles McPhedran, attorney for Earthjustice, which represents Sierra Club in a separate case against Luminant, whose coal power plants spew more than 25 percent of the state’s major source air pollution. “This action will cut air pollution and help these communities breathe easier.”

“The Sierra Club thanks the EPA for protecting Texans against Luminant’s toxic pollution when state regulators would not,” said Nia Martin-Robinson with Sierra Club’s Beyond Coal campaign in Texas. “Today’s filing is a sad reminder that Texas families have been breathing air with too much pollution. People living in the Dallas-Fort Worth area and in East Texas have suffered from too many bad air days where the levels of pollution can trigger asthma attacks and cause respiratory problems for children and the elderly.”

The Clean Air Act requires polluters to obtain permits and install modern pollution controls before expanding a coal plant. This ensures that air pollution sources will be as clean as possible. In addition to soot and smog pollution from Luminant’s coal-fired power plants, in 2011 the Martin Lake plant was the single largest source of dangerous mercury air pollution in the entire United States, according to a report by the Environmental Integrity Project.

“While dozens of other utilities nationwide are investing in clean energy, installing modern pollution controls to reduce pollution and retire aging coal plants, Luminant stands out as one of the Nation’s very worst actors. It burns the dirtiest possible coal—known as lignite—and has repeatedly refused to install modern pollution controls,” added Martin-Robinson. “From ‘do not eat’ mercury advisories for fish in Texas streams to the red and orange smog days in Dallas, Fort Worth, and Tyler, Texans have suffered from coal pollution for too long. Texas wind is providing clean power while creating jobs and increasing property values. The writing’s on the wall—it’s time for Energy Future Holdings and Luminant to clean up their act.”

Read the U.S. Environmental Protection Agency’s previous Notice of Violation.