NRC allows nuclear plants to propose alternatives to its new seismic safety assessment

On Friday, the Nuclear Regulatory Commission (NRC) wrapped up a two-week long inspection of Vermont Yankee’s emergency systems.The biennial inspection is meant to target any holes in the nuclear plant’s emergency preparedness program. Regulators looked at how the facility has responded to emergencies in the past, analyzed staffing levels and tested alarm systems.

While federal inspectors have 45 days to issue a report of their findings, NRC spokesman Neil Sheehan said that a preliminary review of their inspection did not unearth “any significant issues.”

This inspection comes after the NRC issued a new guidance on Sept. 4 for assessing seismic hazards in nuclear facilities across the country. The “supplemental guidance,” as the NRC puts it, is based on recommendations made by a high-level federal task force, which was formed in the wake of the Japanese Fukushima Daiichi disaster to review NRC regulations and processes to identify areas of improvement.

The new guidance is not mandatory, and a leading nuclear expert doesn’t think it goes far enough to protect the public.

Earlier this summer, NRC regulators began inspections with nuclear plant personnel, called “walkdowns,” where personnel and inspectors looked for readily identifiable flood and seismic hazards. But the new guidance, said Entergy spokesman Rob Williams, would require a further-reaching scientific analysis of a nuclear plant’s ability to stand up to an earthquake.

“The seismic evaluation is about the math involved and how the plants are analyzed,” said Williams.

NRC is allowing nuclear facilities to weigh in on the new regulatory measure until Oct. 10, and facilities can propose their own methodologies for how their plants should be inspected for failures.

When Sheehan was asked about nuclear operators preparing their own guidelines, he said NRC could veto their proposals.

“We could deem that methodology and the result unacceptable,” he said. “There is that risk on the part of a company.”

But, he said, most plants appear to be in favor of the assessment process. “Most of the plants have indicated that they plan to adhere to this guidance,” he said.

Williams, however, did not indicate whether Vermont Yankee would conform to the federally proposed guidance.

“We’re going to be reviewing that guidance with the rest of the industry and responding as a group within the timeframe they expect,” he said.

Not enough?

Burlington’s Arnie Gundersen, a nuclear engineer and one of the world’s leading authorities on nuclear safety, said the new guidance doesn’t go far enough to ensure citizen well-being.

“They nibble at the edges of the problem,” Gundersen about NRC’s new guidance. “You’re not going to find the significant changes that really need to be implemented because the plants can’t afford to implement them. You can’t make the changes in an (old) operating plant, and the NRC knows that, so they’re going to try to go around the margin.”

He said the guidance, as proposed, might lead to slight structural improvements but wouldn’t bring about the replacement of 30- to 40-year-old plants, which he considers necessary to prevent nuclear disasters.

One of the central issues with the U.S. nuclear industry, as Gundersen views it, is that low-probability, high-consequence natural events have threatened and, in the case of Fukushima, caused nuclear disaster. As examples of close calls, he pointed to the earthquake in Virginia near the North Anna Power Station and the floods near the Fort Calhoun Power Plant in Nebraska that pushed but didn’t exceed the boundaries of those plants.

“If you look at what we’ve learned in the past five years, we’ve learned that Mother Nature is unpredictable and our predictions have been wrong four times,” said Gundersen.

John Ebel, director of Boston College’s geophysics laboratory Weston Observatory, said it’s very difficult to predict earthquakes in New England because of the short historical record that is available. The largest quake on record in New England hit Cape Ann, Mass., in 1755 and came in at around 6.0 on the Richter scale.

Weston Observatory records show that in 2002 there was a magnitude 5.1 earthquake in New York across Lake Champlain from Addison County, and in 2010 there was a magnitude 5.0 quake just northwest of Montreal.

Despite the seismic unknown of New England’s future, Ebel maintained, “Engineers can design and build structures that can survive even the strongest earthquake shakes.”

But, said Gundersen, the finances aren’t in favor of replacing the country’s aging nuclear plants.

“It does boil down to money,” he said. “A nuclear plant can be safe or it can be competitively priced, but it can’t be competitively priced and safe from these low-probability events.”

The fiscal element of the nuclear equation, said Gundersen, is the reason the industry has so much sway over regulatory policy, as it does over the guidance just issued by the NRC.

“That’s typical,” said Gundersen of the non-mandatory guidance. “That’s the industry influence, where if (federal policy) gets too expensive we won’t hold you to it.”

“Look at each one in a vacuum”

In March, Vermont Department of Public Service Commissioner Elizabeth Miller wrote to William Dean, NRC regional administrator, to ask why a string of human performance errors at Vermont Yankee didn’t require additional oversight from the NRC. Such errors led to the loss of shutdown cooling and some malfunctioning equipment.

Dean responded to Miller, writing that all of these errors were labeled “green,” which means they have ”very low safety significance.” Since none of the findings exceeded the NRC’s “green” threshold, Dean found no reason for additional oversight.

Miller wrote to Dean again in August about similar human performance-related errors, pointing to eight other issues that arose since her March letter. Such incidents included an absent risk analysis, a missing flood seal and a poorly installed condenser.

“My concern is that such incidents, while perhaps unremarkable in isolation, together may raise questions regarding the training and oversight exercised by the operator of the plant,” wrote Miller.

Gundersen has similar concerns.

“These incidents lead me to believe that either the procedures suck, the staff is too young or there’s inadequate training — none of which does the NRC want to address,” he said. “They prefer to look at each incident in a vacuum.”

When Miller was asked about the NRC’s method of analyzing isolated instances, she was frank.

“That’s just how NRC does everything,” she said. “It’s not for me to say whether their oversight should be more holistic or less holistic … It’s the NRC’s jurisdiction and oversight to exercise, but that doesn’t mean we shouldn’t ask questions. In fact, I think we should ask even more questions. That’s the spirit behind the first letter way back in March and the spirit behind the second letter.”

On Sept. 14, Dean wrote back to Miller. While he said that the incidents didn’t warrant increased NRC oversight, he did say that he welcomed a state engineer to join NRC inspectors during an upcoming inspection.

“We plan to conduct a PI&R (Problem Identification and Resolution) follow-up inspection in October 2012 focused on corrective actions to prevent human errors when taking equipment out of service in response to the loss of shutdown cooling in October 2011, and the trip of the ‘A’ emergency diesel generator fuel rack in November 2011.”

When Sheehan was asked about the frequency of the PI&R inspections, he said they should be conducted biennially. The last inspection of this nature, which he referenced, occurred in 2009.

“At that time, we found (Entergy’s) corrective actions addressed the identified causes of problems and were typically implemented in a timely manner,” wrote Sheehan in an email about the last PI&R.

Miller said she welcomes the October inspection, and appreciates Dean’s more thorough response to her concerns.

“I thought that the letter they sent this time, as opposed to last time, was more specific,” she said. “But, overall, my message to Bill Dean was that we do view (our) Department’s role, in part, to review these documents, raise questions when they come up and ask NRC for a response. So he should anticipate that.

“If there are further incidents with the plant, we’ll have further questions.”