Duke Energy said Monday that results from water samples collected downstream of a flooded North Carolina coal ash dump show no negative impacts to the Cape Fear River.
The data Duke released were from a sample collected over the weekend after a dam breached Friday at the reservoir for the L.V. Sutton Power Station near Wilmington. The results from the sample tested in Duke's in-house lab are very similar to the data collected upstream of the breached dam, with no elevated readings for lead, arsenic, selenium or other toxic heavy metals contained in coal ash.
Inspectors from the N.C. Department of Environmental Quality also collected samples of the river water. Officials said those results should be available later in the week.
Flooding from the aftermath of Hurricane Florence overtopped a dike at the plant's 1,100 acre reservoir, flooding an adjacent dump containing 400,000 tons of coal ash.
Wide swaths of gray material could be seen floating in the lake and river over the weekend. Duke maintains those were harmless "coal combustion byproducts," but not the toxic components of coal ash that could threaten wildlife and drinking water supplies.
Environmental advocacy groups also collected samples of the river water that are being tested at a private lab.
Sutton Lake is the former cooling pond for a coal-fired plant Duke retired in 2013 and replaced with a new generating station running off natural gas. Duke said that power plant was shut down overnight and all employees safely evacuated.
The breach at the Wilmington site is separate from last weekend's reported rupture at a nearby coal ash landfill, which spilled enough material to fill 180 dump trucks.
Duke's ash waste management has faced intense scrutiny since a drainage pipe collapsed under a waste pit at an old plant in Eden in 2014, triggering a massive spill that coated miles of the Dan River in gray sludge. The utility later agreed to plead guilty to nine Clean Water Act violations and pay $102 million in fines and restitution for illegally discharging pollution from ash dumps at five North Carolina power plants. It plans to close all its ash dumps by 2029.
State regulators are also testing samples collected near another Duke plant near Goldsboro where three old coal-ash dumps capped with soil and trees were underwater after the Neuse River flooded last week. Duke said any leaks of ash from the flooded dumps at the H.F. Lee Power Plant appeared "minimal."
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