The state Department of Environmental Protection is taking steps to make sure a coal-ash impoundment failure that devastated Kingston, Tenn., last month doesn't happen here.

By the end of this month, DEP officials plan to have examined the 10 coal-ash slurry basins in Pennsylvania that are large enough to require dam permits, including the old Holtwood ash basin in southern Lancaster County.

"We want to go out and inspect these basins just to give people as much peace of mind as possible," DEP spokeswoman Teresa Candori said.

Power companies operating coal-fired plants take the ash from burned coal, mix it with water and store the sludge in slurry basins.

On Dec. 22, a wall holding back 80 acres of sludge at Tennessee Valley Authority's power plant in Kingston failed, spilling about 1 billion gallons of potentially toxic sludge.

No one was injured, but 15 homes were damaged by the flood.

From 1954 through 1999, PPL operated a coal-fired power plant at its Holtwood facility. Now, the facility generates only hydroelectric power.

According to Candori, PPL has a coal-ash slurry basin on its property. It was used when the coal-fired plant was in operation.

The basin has a retaining wall that's 45 feet tall and is considered a "high hazard" dam by DEP because "significant damage" could be caused if it fails," Candori said.

However, the coal-ash sludge was removed and the basin filled in with dirt several years ago, after the coal-fired plant was torn down, PPL spokesman George Lewis said.

"If you went down there, the only way you'd know there used to be a basin there is from the retaining wall," Lewis said. "But since the wall is there, the state still considers it a dam."

DEP officials inspected the Holtwood basin in November as part of the agency's annual inspection program of these structures all over the state.

No problems were found at that time, Candori said.

In the wake of the Tennessee incident, Candori said DEP officials will inspect the Holtwood basin again this month.

"We're doing this just to reassure people that we are doing all we can to make sure these (basins) are safe," she said.

E-mail: preilly@lnpnews.com