Contaminated groundwater at power plants in Gaston and Rowan counties is not flowing toward private wells, Duke Energy said Monday.
Duke, in groundwater analyses that will be reviewed by the state environmental agency, said no imminent health or environmental hazards exist near its Allen and Buck power plants.
Neighbors of the plants have been hardest hit by the results of statewide tests of private wells near Duke’s plants.
Through Aug. 18, owners of 128 private wells near Allen had been advised not to drink their water. Buck’s neighbors have received 78 advisories.
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Duke said Monday’s results add weight to its argument that natural sources, not coal ash stored at the power plants, is responsible for the contamination.
“We see this as a really encouraging milestone for the neighbors,” spokeswoman Erin Culbert said.
Neighbors of both plants responded skeptically to Duke’s findings that contamination hasn’t gone off site at either power plant.
“I find it very interesting that our water is so smart that it can turn around at the boundary line,” said Belmont’s Amy Brown, a community leader in the neighborhood near the Allen plant.
The groundwater assessments found vanadium, one of two constituents found in many of the private wells, widespread on both power plant sites. Duke did not report results for hexavalent chromium, which may cause cancer, citing lack of time to collect and analyze data.
The state Department of Environment and Natural Resources reported last week that contaminants found in the private wells were also detected in wells not affected by ash ponds.
Duke’s studies were required by the Coal Ash Management Act enacted last year after an ash spill into the Dan River. They assessed the direction and velocity of groundwater flows at the power plants, and included readings from wells uphill of the ash ponds.
At both plants, Duke found groundwater generally moves in the direction of the Catawba River, at Allen, and the Yadkin River at Buck. Duke said contamination it attributed to the ash ponds was confined to areas beneath the ponds and downhill of them.
Wells uphill of the ponds, in the opposite direction of groundwater flow, also showed contamination that Duke said came from natural sources.
More samples will be analyzed, and Duke will also do computer modeling of how contaminants in groundwater change over time. Duke will continue to distribute bottled water to neighbors with suspect wells for at least another three months, Culbert said.
“The site assessments are a critical step toward cleaning up coal ash as information contained in the reports will be used by DENR staff to prioritize the closure of coal ash impoundments,” the department said in a statement. “The reports are thousands of pages each and contain comprehensive scientific analysis of groundwater surrounding the coal ash facilities that must be thoroughly analyzed and verified by DENR staff.”
DENR will use the data in assigning priority ratings to Duke’s 32 ash ponds by the end of the year. The ratings will determine when the ponds are closed on a timetable that runs from 2010 to 2029.
Duke has also concluded that groundwater is flowing away from neighbors, or private wells, of five other power plants: Cliffside in Rutherford County, Dan River in Eden, H.F. Lee in Goldsboro, Riverbend west of Charlotte and Weatherspoon in Lumberton.
Duke has acknowledged that contaminated groundwater is moving toward a neighborhood near its Sutton power plant in Wilmington. Duke agreed two years ago to pay for a new water line to the community.
Studies of six more plants are due by Sept. 9.
This article was modified on Aug. 25 to include response from a power plant neighbor.