VERNON — Days after Entergy announced it placed Vermont Yankee up for sale, boasting a record of reliable operation, on-site officials shut the 605-megawatt nuclear plant Sunday night to investigate a leak in the feedwater system piping.
“The decision to shut the plant down was conservative and based on industry experience with feed water systems as well as worker safety,” said Entergy spokesman Larry Smith, who asserted that the leak “poses no threat whatsoever.”
The leaking water, containing multiple radioactive isotopes, including tritium, was captured within a larger system that funneled it back into the feedwater system.
This is the first time the plant has been deactivated for such a repair in the last year. Three similar leaks occurred previously, but Vermont Yankee continued to operate as crews fixed those problems.
According to Smith and Nuclear Regulatory Commission spokesman Neil Sheehan, the leak occurred when a two-inch access plug in the 24-inch feedwater pipe gave way. In the 1970s, engineers drilled the access holes during construction for radiography on pipe welds.
Sheehan said the NRC considers the main water feed pipe to be a non-safety-related system. The agency has sent metallurgical experts to the site who are evaluating the integrity of the piping and other “ports” on the line.
“We want to better understand the faulty weld or other aging and degradation issues,” Sheehan said. “It's better to know this is a port, rather than the pipe wall itself.”
Repair work on the feedwater pipe began Monday evening and took about 24 hours to complete. Technicians, said Smith, plan to replace a degraded seal weld on an access plug with a “more substantial fillet weld.”
The plant will power up once repairs are complete, he said.
This is the first time the plant has been deactivated for such a repair in the last year. Vermont Yankee continued to operate when crews fixed three previous isolated leaks.
VY, a boiling water reactor (BWR), had operated for 163 consecutive days since its last refueling outage before the shutdown.
Plant operators noticed the leak at 9:30 p.m., at the end of the loop before the reactor, during normal hourly observation rounds Saturday. Sheehan said the flow from the “flaw” in the pipe was 120 drops of liquid per minute on Saturday. Smith said leak was 60 drops of liquid per minute and that workers had to pull away piping insulation before finding the leak.
With one line in the system, without any redundancy built in, the plant needed to be shut down, said Smith. The plant shut down around 7 p.m. Sunday.
At the time, said Smith, VY had been operating at 80 percent power during a scheduled rod pattern adjustment and in conjunction with grid line work by Public Service Company of New Hampshire. Rod pattern adjustments, said Smith, occur when the power rods' positions around the core are changed so they control power generation evenly.
The feedwater system
According to the NRC website, BWRs boil water to create steam, which turns the plant's generators. The water runs continuously through the closed feedwater loop.
Smith said the leak occurred in a controlled section of the plant and none of the radioactive water from the leak made it to the environment. The escaped water funneled into floor drains before sub pumps returned it to the feedwater system.
David Spindler, VY senior resident inspector for the NRC, said he had not seen anything in connection with the latest leak to warrant holding the plant back from operating once technicians complete repairs.
But he did say the event was unusual.
“Any plant could develop a leak in any system, but generally you do not find leaks in big systems [like feedwater],” he said.
Dominoes or popcorn?
Arnie Gundersen, a nuclear expert and a member of the legislative Public Oversight Panel, described a similar leak from a port discovered last year. That problem took three days to repair, he said.
“There are dozens more [plugs] throughout the big pipe in the plant,” Gundersen said. “I think you will see more [leaks] in the future. The question is whether they'll go like dominos, or if they'll go like popcorn.”
Gundersen said the problem with degraded welding around the plugs speaks “to the 40-year life issue.” The boiling water reactor wasn't designed to continue operation for more than four decades, he said.
In and of itself, Gundersen said, the main feed is not a “safety-related piece of pipe.” However, he described the pipe as “high energy” - containing water at 400 degrees and under 400 pounds of pressure.
“If the seal had gone [disappeared] all the way around [the port], it would have been a big deal,” Gundersen said.
The NRC has jurisdiction over safety matters, and Sheehan said the agency is concerned with maintaining the reactor itself and the cooling system in the event of an accident.
Vermont's Public Oversight Panel has warned the NRC and the Department of Public Service that Entergy has neglected non-safety systems.
Previous problems with such systems at the plant under the company's ownership - including a transformer fire, the collapse of a cooling tower and the recent discovery of tritium and other radioactive isotopes leaking from the facility's buried pipes into soils - have intensified public and legislative scrutiny of the 38-year-old nuclear power facility. The NRC and Entergy say none of these issues have had an impact on public safety.
Gundersen said that although any one of these problems might happen and it wouldn't be all that worrying for the agency, “you start building this pile and the NRC has got to be saying, 'What are these guys are doing wrong?'”
“It's not anything they [the plant operators] do on a given day,” Gundersen added. “It's the corporate plant managers fighting for money.”
He said Entergy's 11 plants have less money for the repair of non-safety components. “There is a long list of things they know need to be done and they aren't getting done because there isn't enough money in the pot,” Gundersen said.
A sign of larger issues
Last weekend, as the VY leak was discovered, Entergy-owned Indian Point Nuclear Plant in New York experienced an automatic emergency shutdown of one of its generators when a transformer exploded. According to The Associated Press, no one was injured and no radioactive materials leaked into the environment there.
“The gods are not with them,” said Jim Riccio, Greenpeace energy policy analyst.
Riccio said VY and Indian Point share the dubious honor as “problematic” plants in communities with “highly aware populaces.” Also, both reactors, along with Entergy's Pilgrim plant in Plymouth, Mass., are up for relicensing.
“The NRC at this point will relicense anything,” Riccio charged.
According to Riccio, the NRC has relicensed every reactor that has applied for a 20-year extension since Calvert Cliffs Nuclear Power Plant in March 2000. Yankee Rowe in Massachusetts shut down voluntarily before its initial license expired.
“That's not a process. That's a rubber stamp,” said Riccio.
In Riccio's opinion, the NRC “gutted” its regulation program regarding relicensing criteria.
There are good people at the NRC, said Riccio, but they don't hold sway like they used to - especially under former NRC Chair Shirley Ann Jackson, who held the post from 1995 to 1999.
Riccio pointed out that Entergy is also under investigation by the Department of Justice for “non-competition practices.” The DOJ has not responded to Greenpeace's requests for further information.
Furthermore, Riccio said, VY had a “bad reactor design to begin with.”
“Even when on their best behavior, [Entergy] can't operate the reactor without incident, accident or leak. What does that say to a potential buyer or the people?” asked Riccio.
The leak's implications
“[The leak] puts a wrench in the plans,” said Deb Katz of the anti-nuclear group Citizens Awareness Network.
Looking forward, Katz said, there's no reason for the state to issue a certificate of public good - required under state law for the plant to operate - to an aging reactor under the management of a company without a solution for storing nuclear waste anywhere but on the shores of the Connecticut River.
“[Bringing in] another corporation is an attempt to undermine the Senate vote,” Katz suggested.
In February, the Vermont Senate rejected legislation that would have given the Public Service Board the authority to grant VY the certificate of public good.
Katz described Entergy's attempts to win people to its side as a “terror campaign,” charging that the company tried to scare people with the threat of Windham County going bankrupt, households left without power and neighbors losing jobs.
If Entergy cared about its workers, Katz said, the company would have put adequate money into the decommissioning fund to keep workers employed during the estimated 10 to 15 years it will take to decommission the plant.
She said this year, CAN will push for the state to make Entergy accountable for the VY site cleanup after the plant closes in 2012.
Katz said Entergy's mismanagement and the aging plant contribute to the problems at VY. She said Entergy tells people “it's not big deal” when something like the weekend leak occurs on site. But these incidents add up to a “series of no big deals” for which Entergy needs to be held accountable, she said.
“If it's such a good reactor, why are they selling it?” Katz said. “I have no reason to believe any other corporation could do a better job.”
Gundersen similarly warned that the recent crack in the feedwater system pipe, and the January 2009 leak in a gamma port, also in the feedwater system, are indications of an overall cultural issue at VY.
Plant employees have become habituated to Entergy's delayed-maintenance way of doing business - a corporate culture that new leadership can't undo in a few short months, Gundersen predicted. He said the backlog of eight to nine years worth of deferred maintenance at the plant could inhibit a sale.
“I don't see how they're going to get a penny for it,” Gundersen said. “Mother Teresa couldn't turn this plant around in 11 months. We would wind up taking it on faith, and we've taken a lot of stuff on faith already. I don't know how someone can say that by March 2012 it'll be brand spanking new … you can't clean it up that fast.”
Gundersen agrees with Smith that, given the leak's location, the drip will have “no radiological effects on the community.”
He laughed, saying sometimes the two men occasionally agree.
But that's not his concern, he pointed out.
Rather, Gundersen said, he's concerned that other nuclear plants looking to relicense are watching VY.
Seabrook, a 20-year-old plant in New Hampshire, is seeking a 20-year extension to its original 40-year license. To circumvent some of the aging plant issues VY is experiencing, Seabrook is seeking relicensing now based on its current condition, Gundersen said.
Gundersen said seeking a 60-year license on the basis of a plant's 20-year track record is like telling senior citizens they can run a marathon because most adolescents can.
“It's not about physically confirming the condition of the plant,” he said.