STEVENSON, Ala. - Less than three weeks after the Tennessee Valley Authority suffered the nation's worst spill ever at a coal power plant, another pond at another TVA plant on Friday leaked gypsum-laden water into a nearby creek.

At the Widows Creek Steam Plant, the leak from a pipe at a 147-acre gypsum pond was repaired Friday morning, TVA officials said, but not before enough water and gypsum caused a settling pond to overflow into Widows Creek, which flows into the Tennessee River.

The leak was found about 6 a.m. at one of the ponds - located about a mile from the plant - used to store residue from the air scrubber at the Widows Creek plant. An employee found the leak during one of the twice daily walk-throughs conducted by TVA personnel, which have doubled since the Kingston, Tenn., spill, TVA spokesman Gil Francis said.

"They saw something, knew it wasn't right," he said. "They pointed it to everyone's attention."

Mr. Francis said he doubted the leak would have garnered as much attention Friday had the Kingston spill not occurred.

Officials were unsure what caused the leak, how much gypsum leaked into the creek or what other agents may have flowed into it, Mr. Francis said. Gypsum, used in drywall, is not toxic and posed no health risk by spilling into the creek, he said.

"We're doing water sampling and other sampling to determine what, if anything else, was in that material," Mr. Francis said.

He said recent rainfall in the area - more than 2 inches in the past week - did not contribute to the leak.

TVA spokesman John Moulton said the leak did not result in any injuries to plant employees or present any immediate health threats to the community.

"Some material overflowed into Widows Creek, although most of the leakage remained in the settling pond," he said. "We have notified appropriate state authorities."

Jerome Hand, public relations director for the Alabama Department of Environmental Management, said department personnel were sent to Widows Creek on Friday.

"Initially, we did not detect any harm to aquatic life or water quality in the area," he said, "but we are continuing to monitor the water around the plant."

Environmentalists said a second leak at a TVA coal plant in only 18 days raises questions about the integrity of the ash ponds where potentially toxic coal ash is dumped.

"This incident at Widows Creek was obviously much, much smaller than what we saw in Kingston, but the timing for TVA couldn't have been any worse," said Stephen Smith, executive director of the Southern Alliance for Clean Energy, an environmental group based in Knoxville. "These spills highlight the dangers of using wet-ash disposal systems, which we continue to believe should be phased out altogether."

The Widows Creek pond leak was less than .01 percent as much as the Dec. 22 spill from an ash detention pond in Kingston, where nearly 1.1 billion gallons of ash and muck - containing toxic substances such as arsenic, lead cadmium and chromium - blanketed nearly 300 acres of river and land near the Kingston Steam Plant.

Mr. Hand said the Widows Creek spill was the only spill of the type he can remember from one of the ash ponds used to store coal ash at any of Alabama's nine coal-fired power plants.

Peke Wilson, 65, manager of a convenience store and restaurant about a mile from the Widows Creek plant, said his first thought after hearing about Friday's leak was "Kingston." He said he was unaware of similar leaks at the facility and hoped Friday's events didn't cause problems with river water.

"I thought the same thing happened here that happened at Kingston, but here there are places where the water can run off," he said.

Many Stevenson residents were unaware of the leak.

"I didn't even think we'd have something like that here," said Roger Wilson, who had heard about the Kingston event. "I thought it was better here, that it was under control."

The Widows Creek spill attracted the attention of the chairwoman of the U.S. Senate's Environment and Public Works Committee.

U.S. Sen. Barbara Boxer, D-Calif., who questioned TVA's environmental practices during a congressional hearing on Thursday, said Friday that the utility "has a lot to answer for" and she wants a complete assessment from it of what went wrong at both Kingston and Widows Creek.

"This second pollution spill must be a wake-up message to the TVA and to the U.S. (Environmental Protection Agency) that the current situation is unacceptable," she said.