Business & Economy

Entergy replaces radiation monitors; state asks the NRC to investigate “spurious” radiation spikes at Vermont Yankee

Vermont Yankee on the banks of the Connecticut River
Vermont Yankee on the banks of the Connecticut River

Four times since mid-June, monitors have recorded “spurious spikes” in radiation levels inside the Vermont Yankee plant.

The “false positives” for high radiation levels were a result of faulty equipment that produced inaccurate results and did not indicate there were actual increases in radiation in the building that contains the spent fuel pool, according to Rob Williams, a spokesman for the plant.

Entergy notified the Nuclear Regulatory Commission of the equipment malfunction last week.

On Friday, the Vermont Department of Public Service sent a letter to NRC asking for a “full accounting” of the incidents. In addition, Darren Springer, deputy commissioner of the department, insisted the NRC require Entergy to report serious equipment “failures” immediately. The first spike occurred on June 14; the state was notified of the incidents on Thursday. Under NRC rules, Entergy has 60 days to file a report.

Chris Recchia, commissioner of the department, said the false positives are alarming because the radiation monitors are the fundamental warning system for the plant. The monitors, he said, must be perfectly calibrated so that the readings are accurate. “What happens if there was actually a radiation leak and the equipment didn’t register anything or didn’t register the proper amount?” he said.

Springer expressed this sentiment in the official letter to the NRC, which the agency is obliged to respond to. “Failure of the radiation monitoring equipment is a serious issue, and could have under other circumstances led to significant harm if the failed equipment had not detected a radiation release at the plant,” he wrote.

Recchia is concerned about the integrity of the aging nuclear power plant, which was built more than 40 years ago. He says he doesn’t know to what extent the NRC tested safety systems before it relicensed the plant in March 2012 for 20 more years of operation. Springer has asked for “any information on the age and functionality of the failed radiation monitors” that was part of the NRC’s relicensure decision.

“It feels like these systems need to perform accurately, as intended, and we feel like all the systems are aging,” Recchia said.

In mid-June, Entergy officials blamed a loose electrical connection for the “spurious spikes” in radiation, but were unable to locate the source of the electrical problem. When the monitors showed elevated levels of radiation again on July 11, July 23 and July 24, the readings triggered the standby ventilation and isolation safety systems at the plant.

Entergy determined the radiation monitors were faulty and will replace four of the devices. Williams says the monitors “did not fail.” “They remained in service and fully able to perform their safety function,” he said. “We made the prudent decision to replace them.”

“We traced the problem back to the monitors themselves,” Williams said. “It was a false signal.”

Williams said the manufacturer had experienced problems with that particular “lot” of monitor devices. He declined to give the name of the manufacturer.

The radiation incidents are now part of the plant’s corrective action program, according to Neil Sheehan, the spokesman for NRC’s Region 1.

“Replacing the detector and electrical equipment should resolve the issue,” Sheehan said.

The equipment failures did not pose an imminent threat to human health, Sheehan said, because there are other checks and balances in place to protect the safety of workers and the public.

Recchia says he doesn’t understand why the monitor failure is “such a low level incident in NRC’s minds.”

The Vermont Department of Public Service takes a less sanguine view of the incidents. “Common sense would dictate that radiation monitoring equipment be functioning properly 100 percent of the time, and that such equipment failures would be immediately reported to regulators and corrected,” Springer wrote.

Arnie Gundersen, a nuclear analyst and critic of Entergy’s operation of Vermont Yankee, compared the radiation monitoring failures to a faulty check engine light. In this case, it was the light on control panel detecting high radiation near the spent fuel pool, he said.

“It’s another age-related problem,” Gundersen said.

Vermont Yankee has had operational and physical plant problems over the last decade, including a water tower collapse, a transformer fire, tritium leaks, missing fuel rods and condenser issues.

In the last year, the fair market value of the plant has decreased by 69 percent.

According to internal documents from Entergy, the company plans to lay off 10 percent of its workforce at Vermont Yankee.

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Anne Galloway

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  • Mike Kerin

    Another case of Entergy lying and bending the truth. They say the readings were false but they didn’t fail?
    I think Entergy has failed to do what they signed up to do when they bought the plant.

    Shut the plant down and do it right. Fund the decommissioning fund properly.

  • Remember those Louisiana Entergy Yankee leaking pipes that didn’t exist in 2009 but had been reported to the NRC a couple years earlier?

    And now from the very same corporation comes the non-functioning radiation detectors that remain “in service and fully able to perform their safety function”.

    Louisiana Entergy Yankee sounds like the tobacco companies protesting the link between cigarette use and a host of health problems.

  • Craig Kneeland

    The suggestion that 4 or more monitors all failed at the same time is ridiculous. It sounds like a case of shooting the messenger bearing bad news of something more serious.

    The initial response by Entergy that the readings resulted from arcing electrical circuits is equally troubling. We can only imagine the degraded circuits buried underground for 40+ yrs.

  • david klein

    When my ‘check engine’ light goes on in my car, I was told to ignore it by my mechanic until I have to get the car inspected, 99% of the time it only means my catalytic converter is not functioning properly. Yet, when I see the light on, I start to worry. I can’t help it. It is so obvious that this plant is beginning to fall apart, just as the earth’s climate is, yet we carry on, business as usual.

  • Jim Christiansen

    “Arnie Gundersen, a nuclear analyst and critic of Entergy’s operation of Vermont Yankee, compared the radiation monitoring failures to a faulty check engine light”

    Even Arnie couldn’t get worked up over this one.

    I’m no advocate of nuclear power, but claiming the sky is falling anytime a sensor fails does little to strengthen the argument for closure.

    Complex machines break, and they have redundant systems in place for when they do.

    If you trust your government with your health care, certainly you can trust them to inspect a machine.

  • Kathy Nelson

    It seems to me that the staff of VY acted quickly to correct a problem. They also reported the problem and didn’t declare their problems to be a “trade secret” like wind turbine operators do. I’m incline to use David Blittersdorf’s condescending line about wind opponents to describe the nukaphobes as being “just short of crazy”.

  • Howard Shaffer

    The FIRST rule about instruments nuclear power plant operators (and all operators of complex systems) learn is believe your instruments, and act accordingly. History is filled with events where operators said the instrument was wrong without checking.

    The second rule is check other instruments and the plants performance to see if it is behaving as the instrument that alarmed says it is.

    The third rule is verify conditions by backup means.

    For these radiation instruments, there would have been no indication of a leak, low level in the fuel pool, or other things causing a high radiation. Health Physics technicians would have checked locally with portable survey instruments.
    All this will be found in the written procedure to follow for that particular alarm.

    Commenters have forgotten that the Instrument Manufacturer reported problems with this batch of instruments. Have they ever heard of a recall on cars? Same thing.

  • Jim Barrett

    The state didn’t ask for anything but Shumlin and his cronies did ask the NRC to look at VTY. Shumlin constantly throwing stones at private companies for some reason and maybe it is because he is a socialist. The government should control and own everything in his eyes and can do no wrong when in fact we read and hear of how government has and is failing the people they are supposed to serve. The government secrets of invasions of Americans private lives, the lack of our America finding those who gave their all in wars and left to die without accountability to the loving families. Now Leahy pushing for a law that makes it illegal for this government to look at your private emails when many thought our constitution already protected us. This country and government is out of control and m,ay be lost forever.