A federal judge ruled this week that settling ponds used to remove sediment from streams at mountaintop removal coal mines violates the Clean Water Act.

The ruling by US District Judge Chuck Chambers jeopardizes an industry-wide practice that's been used for decades.

Chambers also ruled that the Army Corps of Engineers doesn't have the authority to allow mines to discharge sediment into settling ponds.

Vivian Stockman, a leading environmentalist against mountaintop removal, says the federal court ruling against coal companies that have violated the federal Clean Water Act at the foot of valley fills is just another indication of the success of her group that has opposed the procedure.

Stockman says no one has ever fought the practice before, but her group and others thought it was illegal.

Stockman says it's very likely federal regulators and the industry will appeal the ruling.

"I think the industry is continually flabbergasted that we dare stand up to them," she said. Stockman says they aren't going away.

The corps has long allowed mountaintop removal mines to build settling ponds just below valleys that have been filled with rock and dirt removed to expose shallow coal seams.

West Virginia Coal Association President Bill Raney says the ruling is astonishing because Chambers seems to be attempting to overturn the Surface Mining Act.