Duke Energy told South Carolina regulators Tuesday it will excavate some of the coal ash at its W.S. Lee power plant, which is scheduled to retire within months.
The announcement makes Lee the fifth Carolinas plant at which Duke has said it will, or has been required to, remove ash since a Feb. 2 spill into North Carolina’s Dan River.
Lee, which has operated since 1951, stores 1.7 million tons of ash in two ponds and in one inactive basin unused since the 1970s. An unknown amount of ash is buried as structural fill material and in an ash fill site.
“Based on the engineering work we’ve conducted at the site, we are opting to pursue a fully lined solution for the ash located in the inactive basin and the ash fill, while we continue evaluating the best closure method for the remaining ash,” John Elnitsky, the Duke executive for ash basin strategy, said in a statement.
Remove all of the ash, group says
Environmental advocates said Duke should also remove ash from the two other ponds at Lee, which sits along the Saluda River in Upstate South Carolina, because their dams are unsafe. Metals in ash can be toxic in high doses.
The Southern Environmental Law Center said it has warned since February that ash needs to be removed from those ponds. The law center represents groups that have sued Duke Energy over its ash practices.
Duke’s own consultants have said the dams don’t meet minimum standards, law center attorney Frank Holleman said.
“It’s absolutely necessary those two be removed, too,” he said, to protect the river.
Duke spokeswoman Erin Culbert said the company has evaluated all its ash sites. “Those (Lee) facilities remain safe today, but there are some places where they need repair,” she said.
Ash from the inactive basin will be sent to a landfill, on or off the plant site, or used as fill material to level construction sites. In any case, Duke said, the groundwater under it will be protected by liners, drainage collection systems, a cap over the ash and groundwater monitoring wells.
Capping the ash without removing it wasn’t feasible, Duke said. The inactive basin’s dike walls are steep and would require a lot of tree-clearing. Duke said engineering work is underway to decide how to close the two ash ponds still in use.
Problem keeps growing
After the Dan River spill, Duke said it would excavate ash at three North Carolina power plants – Riverbend west of Charlotte, Asheville and Dan River.
North Carolina legislators, in a measure passed in August, said ash also had to be removed from the Sutton plant in Wilmington. Ponds at Duke’s 10 other North Carolina plants have to be closed within 15 years, the legislation said.
Study is underway of ash at Duke’s other South Carolina plant, Robinson near Hartsville, where 660,000 tons of ash is stored. Robinson’s coal plant retired in 2012.
W.S. Lee will stop burning coal in April. One unit will be converted to a natural gas boiler, and a separate 750-megawatt gas-fired plant will be built at the site.
Duke has scheduled events in Charlotte; Greenville, S.C.; and Danville, Va.; on Wednesday to make a multistate “environmental philanthropic announcement.”