Initial water tests from Duke Energy’s L.V. Sutton Plant in Wilmington confirm that discharges from the cooling lake to the Cape Fear River are not harming water quality downstream.
As the company has previously reported, coal ash basins remain stable.
Water samples captured on Friday upstream and downstream of the Sutton plant site show little to no impact to river water quality. All results are well within the rigorous state water quality standards in place to protect the environment.
There is little difference in river water quality when comparing samples taken upstream above the facility and downstream below the facility. Complete test results and can be found here in the resources section at the bottom of the page.
As previously announced, cenospheres have moved into the Cape Fear River. The company has deployed booms to try to capture any other material before it leaves the lake. Cenospheres are lightweight, hollow beads comprised of alumina and silica that are a byproduct of coal combustion. Importantly, cenospheres have a different chemical makeup than fly ash, bottom ash, boiler slag and other materials, which are the focus of regulation and concern.
Cape Fear River levels near the site are beginning to recede slightly, but we expect the river level to be high for days. The company continues to post photos and video to illustrate the situation at the site.
On Friday, the flooded Cape Fear River began overtopping the north end of the cooling lake, known as Sutton Lake, eventually causing a number of smaller cuts and a larger breach on the southern end where water is flowing back into the river. As flood waters continue to travel through the lake, the smaller breaches are widening. Given the historic level of flooding, this incident is not expected to cause a measurable change to water levels in the area.
There are two coal ash basins at the site, which were being excavated and closed, and their dams remain stable. Water has filled the 1971 basin and the company believes ash is being contained by a steel wall. The 1984 basin has not been affected.
Initial repair plans
As soon as the river stops flowing over the north end of the cooling lake dam and work conditions are safe, teams will begin repairs to stop water exiting the south side of the lake. The objective is to retain as much water in the lake as possible to support future plant operations and recreation.
Sutton Lake is an 1,100-acre man-made reservoir constructed in 1972 to supply cooling water to the Sutton Power Plant. The cooling lake does not store coal ash.
Natural gas plant update
Flooding from the river and cooling lake resulted in about 12 inches of water throughout the Sutton combined-cycle gas plant footprint. The plant was safely shut down. Now plant operators are beginning to assess equipment and will complete those activities as the water recedes. Even without the plant operating, there is adequate electricity to serve customers.