Environmentalists worry the ash-laden sludge that coated a Tennessee neighborhood when a power plant dike burst could pose a health risk, although initial tests by a public utility company have shown no threat to drinking water.
Crews were expected to work through the holiday weekend to contain the aftermath of Monday's breach at the coal-fired Kingston power plant, run by the nation's largest public utility about 50 miles west of Knoxville.
And TVA spokesman Gil Francis said crews were cleaning up the sludge.
"The cleanup is making progress," Francis said Thursday, adding the group was moving from the road to other areas. TVA brought in 30 pieces of equipment and more than 100 workers for the work that will take four to six weeks to complete, he said.
A TVA news release Wednesday said there was no threat to the environment from the breach at the plant near Harriman along the Emory River, which joins the Clinch River and flows into the main Tennessee River.
However, environmentalists have blasted TVA for what they say was something completely avoidable. Hundreds of fish were floating dead downstream from the plant Tuesday, and state and federal agencies have yet to complete water quality testing. Environmental Protection Agency spokeswoman Laura Niles said some toxic metals could be in the muck, including mercury and arsenic.
"The saddest thing is this is entirely avoidable," Evans said. "These people in these communities don't have to be in harm's way. This is not some complicated problem like nuclear waste. This is something the utilities know how to do."
"The holiday disaster shows that there really isn't such a thing as a clean coal plant," Taylor said.
Francis has said the fish may have died from the freezing cold that contributed to the breach, not pollutants.
TVA officials say six inches of rain in 10 days and overnight temperatures in the teens contributed to the rupture of the dike on a retention pond, releasing around 2 million cubic yards of ash, water and mud that covered up to 400 acres. Three homes were destroyed and several others damaged. No one was seriously injured.
TVA officials were working with the EPA and state environmental officials to determine exactly what caused the flood.
The retention pond was one of a series of holding areas where ash generated by the plant was dried until it could be buried or recycled for road beds and concrete. The ash piles at times reached 55 feet above the water.
The bulk of the fly ash "consists of inert material not harmful to the environment," the TVA statement said.
TVA President and Chief Executive Officer Tom Kilgore said TVA may consider using a dry ash treatment process at Kingston that would reduce the chances of a similar event. Five of TVA's coal-fired plants use a dry ash treatment now; the other six, including Kingston, use a wet process.