A federal judge dealt a blow to opponents of mountaintop removal coal mining Tuesday, ruling that the Environmental Protection Agency shouldn’t have set water quality criteria for mining companies.

The Associated Press reports that U.S. District Judge Reggie B. Walton ruled that state regulators, not the EPA, have authority over pollution from the mines. The suit against the EPA was brought by a mining industry group and joined by the states of West Virginia and Kentucky.

Mountaintop removal mining is just what it sounds like. Miners use explosives to take enormous chunks from the top of a mountain and pull out coal seams. The remaining material gets dumped into low-lying areas, including waterways.

Last year, the EPA revised its rules on the practice, banning the dumping of material if it would degrade the nation’s waters or contribute to violations of a state’s water quality standards, or if there are less damaging practices that a company could use. The new ruling dismantles those standards.

Mountaintop removal is the most profitable kind of coal mining and allows coal companies to reach coal that they couldn’t extract in other ways. But the practice has devastated large sections of Appalachian wilderness. According to one study, 5 percent of southern West Virginia has been converted to mountaintop mines, and pollution from the mines is so significant that 22 percent of streams may qualify as impaired under state rules.

The mining industry argues that mountaintop removal is an important source of jobs, but many locals don’t agree. Although the United Mine Workers of America has been fairly supportive of the mining practice, there is significant opposition to it among workers in the area.

Image credit: iLoveMountains.org/Flickr