The Sierra Club, West Virginia Highlands Conservancy and Ohio Valley Environmental Coalition filed the three lawsuits in federal court in Huntington.

The groups accuse Alex Energy Inc. and Fola Coal Company LLC of contaminating water in tributaries of Twentymile Creek with sulfate and other harmful chemicals. The other suit alleges that Consol of Kentucky's Peg Fork mine discharges unlawful quantities of selenium into nearby streams.

Selenium is a naturally occurring element that surface mining can release into waterways. In humans, high-level exposure can damage the kidneys, liver, and central nervous and circulatory systems.

A bill making its way through the Legislature would allow the state Department of Environmental Protection to raise the allowable levels of selenium in lakes and streams. It also would order a study to determine acceptable levels of selenium specific to West Virginia.

The bill says that the federal Environmental Protection Agency has been considering revising the selenium standards for several years, which raises questions about the usefulness of the current standards. The EPA would have to approve the changes.

The groups, which have spent years suing coal companies over water pollution, also have threatened federal regulators with legal action if they do not rein in state regulators. The Legislature last year passed weaker water-quality standards that resulted in 173 streams that would have made the list of impaired waterways being left off the list. Being placed on the list means a plan must be developed for improvement.

"Rather than forcing the mining companies to clean up the impaired streams, WVDEP is trying to redefine the meaning of impairment administratively so that it no longer exists while the EPA is taking a `cross your fingers and hope' approach to mining pollution," Jim Sconyers, chapter chairman of the West Virginia Sierra Club, said in a release. "So groups like ours have to do WVDEP's job. We can't allow these companies to keep poisoning our streams."

Representatives for Alpha Natural Resources, which owns Alex Energy, did not immediately return a phone messages seeking comment.

It is the policy of Consol, which owns the other two mines, not to comment on pending litigation, spokeswoman Lynn Seay said.

"CONSOL Energy strives to be a good corporate citizen in the communities where we operate, and as such, we strive to comply with all of our regulatory, contractual and other legal obligations," she added. "Once we have had a chance to review these complaints, we will respond appropriately."

Mountaintop removal is a particularly efficient but destructive form of strip mining that blasts apart mountain ridge tops to expose multiple seams of coal. The practice of flat-topping the mountains, then filling valleys and covering streams with rubble has divided communities and led to confrontations between coal miners and environmentalists.

Consol was ordered to pay a civil penalty of nearly $270,000 in a settlement reached in December with state regulators concerning violations at its Peg Fork mine in Mingo County. The groups argue the settlement doesn't specify a timeframe for the company to bring its selenium discharges into compliance. They also argue the penalty was not adequate "to disgorge Consol of its economic benefit of noncompliance."

Such lawsuits are prohibited as long as the state has "commenced and is diligently prosecuting" to require compliance. But the groups argue the state is doing so, which "leaves a realistic prospect that Consol's unlawful selenium discharges will continue," the groups allege.

They are asking the courts to require the companies to abide by pollution regulations or to pay civil penalties up to $37,500 per day for each violation.