The state Department of Environment and Natural Resources said the two notices relate to separate violations of wastewater and stormwater regulations. The agency could levy fines against Duke for the violations, but the amounts have not yet been determined.
The spill began Feb. 2 when an old stormwater pipe running under a 27-acre coal ash dump at a Duke's Dan River Steam Station in Eden collapsed. It took the company nearly a week to fully plug the leak.
State environmental Sec. John Skvarla, whose agency has been widely criticized in the wake of the spill, issued a brief statement: "These are violations of state and federal law, and we are holding the utility accountable."
The violation notices were issued three days after The Associated Press filed a public records request for a copy of Duke's stormwater permit for the Dan River plant, which the company was required to have to legally discharge water draining from its property into the river. Such a permit may have required testing and inspections that could have given early warning something was wrong before the collapse.
The agency responded that no such permit existed.
In a written statement, spokeswoman Bridget Munger said the state had historically considered the stormwater pipes at the plant to be part of the facility's wastewater permit covering discharges from the ash basins. State regulators had been talking with Duke since 2011 for the company to apply for the required stormwater permit, but that issue had not been resolved by the time of the spill, she said.
"Staff members in the department's stormwater permitting unit have been working since that time with Duke Energy to develop a template for individual stormwater permits for all of their facilities that have coal ash ponds," Munger said Wednesday. "Some progress has been made but there are still many issues to be resolved, including monitoring, parameters for testing and other requirements."
Asked for clarification Wednesday on whether Duke was in violation of state and federal laws for not having the required stormwater permits, the agency refused to answer. It was not clear why Duke was not issued notice it was in violation of environmental standards for lacking the required permit during the years before the spill.
After issuing a news release on the issuance of the violation at 5 p.m. on Friday, agency communications director Drew Elliot did not respond to voicemail or email messages seeking comment.
Frank Holleman, a senior attorney for the Southern Environmental Law Center, expressed dismay that the state regulators had knowingly allowed Duke to operate without the required permit for years.
"It is unbelievable that Duke would knowingly have discharges from these stormwater pipes without a permit and that DENR would allow them to do it," Holleman said. "Someone needs to explain why this happened."
The second violation notice issued Friday was for failing to prevent the massive spill and exceeding state water-quality standards in the river, which tests showed had high levels of arsenic, lead and aluminum — metals contained in coal ash. Public health officials have advised people to avoid contact with the river water and to not eat fish.
The notices of violation invite Duke to respond within 15 and 30 days with any information on why the company should not be issued fines.
Asked for comment Friday, Duke Energy spokeswoman Paige Sheehan responded: "We will reply to the state."
Amy Adams, a former state water-quality regulator who now works for the environmental group Appalachian Voices, said the violations come too late to help the Dan River.
"This is protocol. It's just a piece of paper until and unless there is rigorous enforcement that follows," Adams said. "This would have been appropriate had the coal ash spill come as a surprise, but the fact that DENR and Duke Energy both knew full well and long ago of significant coal ash problems at all of the company's facilities, well, the phrase, 'too little, too late,' comes to mind."
Duke operates 14 sites across North Carolina that contain at least 32 coal ash dumps.
Word of the violations for the Dan River spill came as state regulators also expressed concern Friday about potentially contaminated water trickling from a stormwater pipe at a different Duke coal ash dump, this time at the Cliffside Steam Station in Rutherford County. That pipe drains an emergency stormwater basin built on top of an old coal ash dump, but is only supposed to drain water in severe storms.
State officials said the corrugated metal pipe is heavily corroded and taking in groundwater, which is draining out at a rate of more than 1,100 gallons a day. Duke staff are sampling the potentially contaminated groundwater coming from the pipe for toxic metals associated with coal ash.
The pipe empties into rocks a few feet from the Broad River, but the agency said there is no indication the flow has reached the waterway.
"Fortunately, we observe no environmental impacts from this discharge," said Tom Reeder, director of the N.C. Division of Water Resources. "However, we need to emphasize increased attention to all aspects of the infrastructure at Duke Energy's facilities across the state."