GREENVILLE, N.C. (AP) -- As the nation's largest electricity company prepares to plead guilty to violating the federal Clean Water Act, Duke Energy has started delivering bottled water to people with tainted wells close to its North Carolina coal ash pits.
Duke has long denied its 32 dumps in the state have contaminated the drinking water of its neighbors, suggesting any worrying chemicals found in the wells is likely naturally occurring.
But recent state-mandated tests found that more than 150 residential wells tested near Duke's dumps have failed to meet state groundwater standards, and residents have been advised not to use their water for drinking or cooking.
Many of the results showed troublesome levels of toxic heavy metals like vanadium and hexavalent chromium — both of which can be contained in coal ash. And some of the residents have retained lawyers.
Duke spokeswoman Erin Culbert told The Associated Press that any homeowner who gets a state letter warning of a tainted well will get safe bottled water from Duke, if they request it.
While denying responsibly for the problem, Culbert said Duke simply wants to provide the homeowners "peace of mind."
Duke is scheduled to plead guilty Thursday to nine environmental crimes as part of a negotiated settlement with federal prosecutors requiring it to pay $102 million in fines and restitution. The proposed settlement over years of illegal pollution leaking from ash dumps at five of Duke's plants has been sealed, so it wasn't clear before the hearing whether people with contaminated well water will benefit.
The company's Buck Steam Station is not one of the five plants in the negotiated settlement. But nearly three dozen homes surrounding Buck — an area called Dukeville — have received letters warning them not to drink the water.
A year ago, some people in the community held meetings questioning whether the dumps were polluting their wells, causing health problems.
Dukeville resident Ted Rary, whose well is being tested next week, said he was willing to give Duke the benefit of the doubt last year, but now? "I don't trust them anymore," he said.
"I'm like the rest of the people. I want my well tested. And if it's bad, I want Duke to make it right. That's all. It's their responsibility. Just make it right," Rary said
Duke's pledge to pay for safe water in any case was welcomed by Sherry Gobble, who lives with her husband and two young children on land adjacent to Buck. Her drinking well is about 250 feet from the largest of the three open-air coal ash pits at Buck, which together cover 134 acres and contain more than 5 million tons of ash.
Nationally, there are more than 1,100 such dumps, most located near aging coal-fired power plants.
As The Associated Press reported in June, private tests by Waterkeeper Alliance found worrying levels of heavy metals in the wells of Gobble and several of her neighbors in Dukeville, a close-knit rural hamlet named for the large number Duke power plant employees who live there.
Ever since, Gobble has been using bottled water for everything from making coffee to bathing her children. The family goes through about 40 one-gallon plastic jugs each week.
"It takes a lot out of you to haul that water every week — in and out, in and out," Gobble said. "I'm so tired of hauling water."
According to the North Carolina Department of Environment and Natural Resources, Gobble's well contains hexavalent chromium at more than 50 times the threshold set by state health officials, and vanadium at nine times the state's allowed groundwater limit.
The U.S. Environmental Protection Agency says hexavalent chromium is likely to be carcinogenic when ingested. The International Agency for Research on Cancer has determined that vanadium is "possibly carcinogenic to humans." Studies show lab animals exposed to high oral doses of vanadium suffered neurological and developmental problems.
Duke had said its own sampling showed no problems with residential wells in Dukeville until a new state law, passed last year in the wake of a massive spill of coal ash at Duke's Dan River Steam Station, required independent testing of all residential wells within 1,000 feet of an ash pit.
Of the wells tested through the end of April, more than 93 percent failed to meet state groundwater standards.
Even Duke got a warning letter from state health officials, because the well supplying the Buck plant tested higher than state groundwater standards for antimony, a potentially harmful metal found in coal ash.
Duke has for years supplied bottled water to its employees at the plant.
After denying wrongdoing for years, Duke recently conceded in regulatory filings that it had identified about 200 leaks and seeps at its 32 coal ash dumps statewide, which together ooze out more than 3 million gallons of contaminated wastewater each day.
Still, the company insists it is not responsible for contamination in residential wells ringing its coal-fired power plants. Culbert blames natural processes present in local soils and rock, not the company's ash pits, and says more study is needed.
"Based on the state's test results we've reviewed thus far, we have no indication that Duke Energy plant operations have influenced neighbors' well water," Culbert said.
Avner Vengosh, a Duke University geochemist who studies coal ash contamination, agreed that available data does not yet conclusively link or rule out Duke Energy's leaky pits as the source of the well contamination. But he said "I would be very concerned if I lived there."
Duke University and Duke Energy — both named for the same family of North Carolina tobacco barons — are not affiliated with each other.
Waterkeeper Alliance spokeswoman Donna Lisenby said the state's results verify what her group found last year — findings that were waved off by state regulators as well as Duke.
"Instead of disputing our science and our testing, now they have their own results confirming what we've said all along: Wells close to Duke's ash ponds at Buck contain heavy metals and other pollutants that are also in coal ash," she said.