Waterford — A citizens' panel charged with overseeing safety-related issues at Millstone Power Station grilled representatives of the nuclear power plant Wednesday about whether three recent special inspections by the Nuclear Regulatory Commission signal a systemic problem there.

"Are you looking to see if alertness is slipping, or if the care is slipping, or if the attitude is changing?" Bill Sheehan, chairman of the Nuclear Energy Advisory Council, asked three representatives of Millstone owner Dominion during the panel's regular meeting at Town Hall. "Have you looked for a pattern in what seems to be occurring in these dissimilar events, related to materials, or personnel, or training? It worries me that I'm seeing a slow increase" in problems prompting increased scrutiny from the NRC.

"I've got to back Bill up on this," said council member Bob Klancko. "You focus very well on monitoring, but it seems to me that on engineering depth-of-expertise on the operations side, you may be too lean."

Their comments came during the annual presentation by Millstone representatives to the council on the past year at the plant, a meeting that is not typically characterized by pointed remarks and lengthy, skeptical questioning by the council. Wednesday's exchange came after the plant had been subject to a special NRC inspection in May after an unplanned shutdown of both operating plants at the power station, followed by a special inspection of a backup safety pump at Unit 3 this summer and another special inspection of a different problem with the same pump in August.

The May inspection resulted in the NRC issuing a "severity level 3" violation for the plant's power line outage detection system. The NRC determined that plant staff could have taken steps to avoid the sequence of events that led to both units going offline.

The second inspection resulted in a more serious finding, a "white" safety violation of "low-to-moderate" significance, the second-lowest on the four-tier scale used by the NRC. If the finding is finalized, the plant would be put under increased NRC scrutiny for a year.

The third special inspection, prompted by repeated failures on tests of the same pump, began Monday and is ongoing, Millstone spokesman Ken Holt said. The pump has since been repaired and is fully operational, he said.

In response to questions by the council, Lori Armstrong, director of nuclear safety and licensing at the plant, said the first problem with the pump was the result of the installation of a replacement bearing that was mislabeled by the manufacturer. The bearing looked identical to the one it replaced, she said, but it was missing a critical bronze component. It was ultimately detected by "an engineer with a very inquisitive mind," she said.

Klancko asked whether the plant's quality control procedures for replacement parts have been examined, and whether the plant has sufficient staff with metallurgy and materials expertise.

Armstrong said that in response to the inspections, 180 Millstone staff have participated in training to improve "rigorousness of troubleshooting." She agreed with one member of the council that three special inspections in less than six months is "a lot."

"We have recently hired some additional talent, including a corrosion engineer," she added.

Council member Jeffrey Semancik, director of the Radiation Division at the state Department of Energy and Environmental Protection's Bureau of Air Management, also suggested that the repeated special inspections should cause the plant managers to be circumspect about reaching conclusions about the three incidents too quickly.

"Is there a common cause, something that you're missing?" he asked.

Sheehan said Thursday that he was satisfied by some of the responses from Millstone representatives, but not by others. He said the critical issue now is how Millstone pursues the issues raised by the council. In addition to hearing reports from Dominion about Millstone, council members also receive reports from the NRC about the inspections.

"You don't fix this overnight," he said.

NRC spokesman Neil Sheehan, who is not related to Bill Sheehan, said Wednesday that the agency is "always looking for commonality as far as issues at the plant."

"We do want to know if it's a training issue or if it's systemic," he said.

After the current special inspection concludes, he said, the inspectors will conduct an exit meeting with Dominion officials and issue a report within 45 days. During the meeting, the inspectors will tell Dominion their preliminary conclusions. The malfunction of the pump, he added, is a serious concern because "it's an important component" needed to operate the plant safely.

He said the NRC has not yet heard from the advisory council about its concerns but added that the agency is in regular communication with DEEP staff and "would encourage them to share any details of concerns brought up during the session."

Holt, the Millstone spokesman, said the in-house investigation of the three incidents that prompted the special inspections did include a root cause analysis of whether there is a common underlying problem.

The NRC has not levied any fines as a result of the three incidents, but it is charging Dominion for the cost of the special inspections.

j.benson@theday.com

Twitter: @BensonJudy