STEVENSON, Alabama - The Tennessee Valley Authority has had a second waste spill in three weeks at one of its coal-fired power plants.

A 10,000 gallon leak of process water from the gypsum pond at the Widows Creek Fossil Plant in Stevenson, Alabama was discovered just before dawn this morning. TVA officials say the leak has stopped.

"The leak from the gypsum pond flowed into an adjacent settling pond," the federal electric utility said in a statement this morning. "Some material overflowed into Widows Creek, although most of the leakage remained in the settling pond."

Gypsum ponds hold limestone spray from TVA's scrubbers that clean sulfur dioxide from coal-plant emissions. Gypsum contains calcium sulfate, which is used in drywall, a commercially sold construction material.

Widows Creek Fossil Plant, named for the creek that flows through the plant site, is located on Guntersville Reservoir on the Tennessee River in northeast Alabama.

TVA notified federal and state authorities and has deployed containment booms on Widows Creek to trap the contaminated water. The utility says it will perform temporary repairs to the pond.

Alabama Department of Environmental Management spokesman Scott Hughes told ENS that the agency has a crew on the scene monitoring Widows Creek for effects of the spill on aquatic organisms in the creek.

"At noon there was no sign of impact to aquatic organisms," he said.

The city of Scottsboro about 15 miles downstream from the Widows Creek Fossil Plant uses the Tennessee River as drinking water. Hughes explained that any contamination from the spill has not had time to reach this community.

ADEM personnel will provide oversight to ensure cleanup is done in a timely manner, said Hughes.

The eight coal-fired units at Widows Creek generate about 10 billion kilowatt-hours of electricity a year, enough to supply 650,000 homes. The plant consumes some 10,000 tons of coal a day.

This leak is the second at a TVA coal-fired power plant in the past three weeks. On December 22, a retaining wall broke at the TVA's Kingston Fossil power plant in eastern Tennessee's Roane County, about 100 miles to the northeast of Widows Creek. A billion gallons of coal ash sludge spilled into the Emory River and across 400 acres of the surrounding farm and residential neighborhood.

"Even as residents in Roane County Tennessee are still trying to grasp the full impact of the Kingston disaster, communities in northeastern Alabama are now threatened with a new toxic coal waste spill," said Bruce Nilles, director of the Sierra Club's National Coal Campaign.

"While initial accounts indicate that this latest spill is smaller than the Tennessee disaster, we hope that TVA and EPA have learned from the Tennessee disaster and move quickly to protect residents," said Nilles.

John Wathen, an Alabama resident with Hurricane Creekkeeper, was in Tennessee taking stock of the Kingston disaster when he heard about today's spill.

"If this don't stick a finger in the whole clean coal myth, then I don't know what will," said Wathen.

Coal waste can contain harmful substances including lead, mercury and arsenic.

Once spilled, the toxins from the waste can leak into soil and water, putting people who come in contact with the contamination at risk for health problems.

"Shockingly, coal waste is largely unregulated in Alabama," said Gil Rogers, staff attorney for the Southern Environmental Law Center in Chapel Hill, North Carolina.

"Alabamans deserve straight answers from the Alabama Department of Environmental Management about how it's handling this waste stream at TVA's Widow Creek plant and if any corrective action procedures are in place to deal with it.

ADEM's Hughes told ENS, "We inspect all these facilities on an annual basis. Our focus is to ensure the water discharged from these impoundments comply with their National Pollutant Discharge Elimination System permits. The lastest inspection at Widows Creek took place on May 21, 2008, and Hughes says inspectors found no violations.

"Clearly current regulations are not adequate," said Nilles. "We need the Environmental Protection Agency to start regulating coal ash before more communities are put at risk."