Indian Point Transformer Fire

Diane Screnci
Senior Public Affairs Officer
Region I

NRC inspectors are following up on a transformer fire at Indian Point Energy Center over the weekend. The NRC Resident Inspectors for Indian Point – who work at the plant on a daily basis – are monitoring activities at the site while plant workers are troubleshooting and looking for the cause of the fire on the Unit 3 main transformer.

The transformer fire happened at about 6 p.m. on Saturday night. A sprinkler system initially extinguished the flames, but it reignited and was put out by the onsite fire brigade and local fire departments. The fire caused the reactor to automatically shut down, as designed. All safety systems worked as designed. There was no danger to the public and no release of radiation. The reactor is stable. Unit 2 continues to operate at full power.

Plant operators declared an “unusual event” – the lowest of the emergency classifications – in accordance with plant procedures. All plants have procedures, approved by the NRC, that dictate how events are classified to ensure appropriate steps are taken to respond to the event and to communicate the event to local and state agencies and the NRC.

In addition to cooling provided by fans, the main transformer is also cooled by oil flowing through it. On Saturday, oil from the transformer spilled into the plant’s discharge canal. Entergy has been working to determine how much oil was spilled.

The transformer that failed carries electricity from the main generator to the electrical grid. The same type of equipment can be found at any plant that generates electricity. It is on the electrical generation side of the plant – not the nuclear side.

As far as next steps go, plant employees will determine what happened and why. They will repair or replace any equipment that was damaged in the fire. The plant can restart when ready. NRC inspectors will be monitoring Entergy’s actions every step of the way, ensuring workers are taking all appropriate actions.

As we do with any event at a plant, we’ll continue to review what happened and how the plant responded. If need be, we’ll send additional inspectors to the site to look further into the event and its effects.

Author: Moderator

Public Affairs Officer for the U.S. Nuclear Regulatory Commission

41 thoughts on “Indian Point Transformer Fire”

  1. Most nuclear power plants have several dozens of institutions and programs, each of which could have or should have prevented this event and each of its harmful outcomes by simple, prudent, compliant, competent, businesslike activity. Please list them all. Please ask IPEC to list them as failed, missing, and/or ineffective barriers in the root cause evaluation/ analysis.

  2. Who were the individuals and organizations that had opportunities to identify the harmful conditions, behaviors, actions, and inactions that resulted in the failed transformer, the failed fire suppression (reflash), the loss of the oil, the failure of the flood barriers, the failure of the pollution prevention measures, etc. before the event?

    How come each of them failed?

    How come they all failed?

    Is this a fair sample of how the U.S. nuclear power community performs?

    What is the extent?

    You can get an inkling by reading NRC Information Notices.

  3. Dan,

    Your concerns are valid.

    I would like NRC and the industry to arrest the serious trend in downstream identified safety noncompliances that threaten nuclear power as a non-GHG emitting power option.

    What’s your approach?

  4. Are you going to hold an entrance meeting for this special inspection you’re conducting here? Will you be billing the NRC for all these postulated questions, or is this just your display of altruism? Do you have a bottomless barrel of questions?

  5. If there are any NRC requirements, which, had they been adhered to, would have prevented the actual discharge to the river the way it happened, then noncompliance with them was a cause of the discharge.

    These requirements could involve the care of the transformer, the care of the berm/moat, the root cause analyses of earlier events here, and/or the handling of industry operating experience and industry “standards.”

    This should be a line of inquiry.

  6. A colleague posted elsewhere:

    While the oil leak is embarrassing, to me the bigger issue is the transformer failure. To be honest, I don’t care about the oil in the Hudson. The oil spill shouldn’t have happened, and needs to be investigated, but the oil can be cleaned up. It’s not the significant issue though.

    This isn’t a recent problem of aging transformers. Many relatively new transformers (like this one) have failed. INPO issued Significant Operating Experience Report SOER 02-3 “Large Power Transformer Reliability” in 2002, but the industry continues to have significant issues in 2015. I’m sure that you know that SOERs are rare because they deal with “significant” issues. This isn’t just a large power transformer issue. Many plants have had lower voltage transformers fail, resulting in a fire and declaration of an Alert. I’m not sure why EPRI hasn’t addressed this. This is not only embarrassing to the industry, this is a safety concern since an Unplanned Scram or loss of a safety bus challenges safety systems.


  8. If there are any NRC requirements, which, had they been adhered to, would have prevented the actual discharge to the river the way it happened, then noncompliance with them was a cause of the discharge.

    This should be a line of inquiry.

  9. There is a rock-filled moat surrounding the main transformers at Indian Point. Its purpose is to capture oil that is released from a transformer should it fail. We are still reviewing the event.

    Neil Sheehan

  10. Our review of the May 9th transformer failure event at the Indian Point 3 nuclear power plant is still under way. We will be providing our findings in an upcoming inspection report.

    Neil Sheehan

  11. The question is still relevant and valid.

    Please list all of the NRC requirements, which, had they been adhered to, would have prevented the actual discharge to the river the way it happened?

  12. As the moderator stated elsewhere, oil discharges to bodies of water af under the purview of the New York Department of Environmental Quality and apply not only to nuclear plants but at any generating facility using oil filled transformers.

  13. Please list all of the NRC requirements, which, had they been adhered to, would have prevented the actual discharge to the river the way it happened?

  14. Was it a “dike”, a “dyke”, a “berm”, a moat”, or what? How is it described in the plant drawings? How is it described in the Updated Final Safety Analysis Report?

    At any rate it did not do what was required. This means, in plain engineering English, it failed.

    An item fails when its service demand is not met by its service capability.

    What conditions, behaviors, actions, and inactions resulted in the failure?

    What were the earlier, better, cheaper, safer, more compliant ways that those conditions, behaviors, actions, and inactions and their causations could/should have been discovered?

  15. That’s a question for the New York State Department of Environmental Conservation.

    Diane Screnci

  16. Dan W,

    I was at that meeting. I felt uncomfortable and wished the police would have yanked him from the room. There were four or five police officers in the room, plus a contingent of other than NRC federal officials in the room. For those few hours, I am convinced it was safest space in all of New England. Believe me, they were all checking me out?

    I spent my time up at the podium profusely thanking the police officers for putting up with our antics and for doing their difficult day to day jobs in our area. I also thanked the NRC for being there. I was trying to say, I was going to miss the big foot print of the NRC operating staff.

    I was the only one there both pro, anti and NRC who thanked the local police at the podium for doing their difficult job over the ending of operating Vermont Yankee.

  17. Unfortunately, the NRC has had “inconsistent” results in conducting public meetings outside the confines of Rockville, MD. Their recent experiences in Vermont have done little to “create much better public transparency” or to “enhance” their credibility. And I suspect you know full well how such a forum as a premature press conference would be co-opted by the likes of Gary Sachs and turned into a circus. Witness…

  18. “Transformer oils (mineral oil) are subject to electrical and mechanical stresses while a transformer is in operation. In addition there is contamination caused by chemical interactions with windings and other solid insulation, catalyzed by high operating temperature. The original chemical properties of transformer oil change gradually, rendering it ineffective for its intended purpose after many years. Oil in large transformers and electrical apparatus is periodically tested for its electrical and chemical properties, to make sure it is suitable for further use. Sometimes oil condition can be improved by filtration and treatment.”

    It is interesting, they traded increased flammability and the instability of mineral oil for the human health concerns and inflammability of the horrendous PCBs. When the plant was new these transformers were loaded with PCBs,

    Has the flammability of mineral oil versus the inflammability of the notorious PCBs been accounted for in plant licensing? Nonflammable PCBs in transformers was the choice in the construction era for most plant licensing…have they updated all their licensing documents for flammable and instable mineral oil on all plant transformers?

    Basically mineral oil is a distillate of petroleum….

    Mike Mulligan
    Hinsdale, NH

  19. Transformer oil is a light-weight mineral oil. Entergy is still working to quantify how much oil was spilled and how much may have made its way to the river.

    Diane Screnci

  20. From NRC Information Notice 2009-10
    A relatively high incidence of transformer failures has occurred in the last few years, the majority of which could have been avoided had the licensee fully evaluated and effectively implemented corrective actions and recommendations identified in industry operating experience. These corrective actions included a more effective maintenance program and a more proactive approach to addressing abnormal indications. In particular, some utilities have installed online automated oil analysis and monitoring system to support decisions regarding preventive and corrective maintenance to improve transformer reliability. The Institute of Electrical and Electronics Engineers (IEEE) provides industry guidance on this matter in Standard C57.140-2006, “IEEE Guide for the Evaluation and Reconditioning of Liquid Immersed Power Transformers.”

    What’s going on here?

  21. What were the constituents of the oil that got into the river?
    Did the berm fail?

  22. I wish the NRC was like the NTSB. The lead investigator just said the NTSB will release all factual information as it is discovered.They immediately released the passenger train was traveling twice the speed limit. I wish the NRC would become more like NTSB. The lead NTSB investigator is answering all questions by the media as I write less than 24 hours after the accident. So they copiously release all discovered factual information to the public, the local community and the victims, then go back to their office to write up the professional report.

    I request that the NRC reevaluate how they release information post all accidents or incidents. I wish within the first 24 hours the NRC would stand out behind a podium in a press conference and answer all press questions.

    This would create much better public transparency and enhance the credibility of the NRC.

    If the agency had a briefings and updates within the first 24 hours on every event like the Indian Point transformer fire, then if a much worst event occured, all of NRC officials will be better skilled and well seasoned at giving the professional style off the cuff a quick NTSB briefing and answering the press. This would lend to enhancing the NRC image in the more difficult events and accidents.

    Mike Mulligan
    Hinsdale, NH

  23. You are correct. The transformer fire did not affect the nuclear side of the plant.

    Diane Screnci

  24. This transformer had been in service since 2007. The life expectancy, typically, is expected to be about 40-50 years. Entergy has a monitoring and maintenance program for the transformers.

    Diane Screnci

  25. How long has this transformer been is service? And is their a life expectancy for a transformer like this? And is their a regular maintenance cycle for power transformer like this?

  26. Paul,
    I yanked that “run to failure” phrase right out of a Pilgrim plant NRC inspection report. They all know I am mocking heck out of the lot of them.

    It is more a addiction to gambling problem..maximizing short term profits over long term gains. They gamble because there are positive incentives, until there is not…

    I doubt they don’t have an onsite spare or it could acquire one quickly.

    The vast amount of transformers used in the USA aren’t manufactured in the USA (95%). I always like USA engineering codes and standards. What foreign country made that failed Indian Point transformer? They use foreign uranium also?

  27. Sounds like a non-event to me, only requiring the local fire department and environmental agency to worry about. Or is there a risk of collateral damage to the nuclear side of the plant?

  28. All NRC emergency classifications should require that at least one if not more independent experts Chosen from a Public Listing, not the nuclear industry be tasked with observing, that way nothing would get swept under the table, and the public would have yet another layer of safety.

  29. “Was it another run-to-failure maintenance philosophe with Entergy?”

    What would be Entergy’s incentive to run a major piece of equipment like this until failure? It’s not like there are huge spare transformers just sitting around. Do you think Entergy is saving money with the plant not producing power?

  30. The NRC resident inspectors are monitoring Entergy’s investigation into the cause of the transformer failure. We’ll assure their investigation is comprehensive.
    Diane Screnci, Sr. Public Affairs Officer

  31. Did the failed transformer have indications of the minor off gassing or contaminants in the oil indicating the transformer was failing prior to the fire? Was there other indications of maintenance problems being unaddressed prior to the fire?

    Was it another run-to-failure maintenance philosophe with Entergy?

    Should the plant have been shut down before the fire and they replaced the degrading transformer?

    Mike Mulligan
    Hinsdale, NH

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