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Continuing to Learn the Lessons of San Onofre

Rebecca Sigmon
Reactor Systems Engineer
Office of Nuclear Reactor Regulation

Almost two years after the San Onofre nuclear power plant shut down permanently, the NRC has kept an eye on what we can learn from the events that led to the plant’s closure. The latest product of this work reviews the agency’s procedures related to Southern California Edison’s (SCE) installation of new steam generators at the plant.

songsThis work builds on our response to the steam generator damage San Onofre discovered in January 2012. At the time, our inspections and reviews aimed to understand what had happened and ensure public safety would be maintained before the plant could restart. Even after SCE decided in June 2013 to shut San Onofre down, the NRC continued its reviews to try to prevent something similar from happening at other reactors.

A year ago, our Executive Director for Operations asked the offices of Nuclear Reactor Regulation and New Reactors, as well as our Region IV office, to review the NRC’s own actions. The effort focused on the event and the NRC’s response to find any areas for improving our processes. The review covers issues raised in a 2014 NRC Inspector General report.

The review examines eight basic topics and discusses 17 actions to enhance what are already effective tools for overseeing U.S. operating reactors. Some of the topics include: better identification of potential design issues before they lead to problems; better assurance that plants comply with our requirements in 10 CFR 50.59, “Changes, Tests, and Experiments;” and improving communications with the public.

The review touched on all aspects of the NRC’s involvement in the San Onofre event, from on-site inspection to Congressional briefings, from technical review to website maintenance. The review team discussed some of these issues with industry experts. The team also sought comments from members of the public who participated in meetings about the San Onofre event and subsequent technical analyses.

The review concludes, among other things, that the 50.59 process is appropriate for plant activities that replace large components, such as steam generators. The review also finds that the staff properly used a Confirmatory Action Letter as an oversight tool in responding to the San Onofre events.

The staff’s already working on many of the review’s 17 actions. For instance, the staff is working on documents that clarify several areas of NRC guidance on following the 50.59 process. The NRC is also working on additional training for agency staff to improve their 50.59 reviews and associated activities. All of this ongoing work will help ensure U.S. nuclear power plants continue to safely operate, maintain and repair their systems.

24 responses to “Continuing to Learn the Lessons of San Onofre

  1. Anonymous March 23, 2015 at 3:27 pm

    The NRC clearly doesn’t learn lessons from the past. SONGS steam generator replacement required prior NRC approval in the form of a license amendment. Per 50.59, a license amendment was needed because Southern California Edison used new and less conservative methods and assumptions in safety analysis supporting use of the new design. The same exact approach Pacific Gas and Electric used to conclude that the new (more capable) earthquake faults are within the Diablo Canyon design basis (Sept 2014). The NRC not only doesn’t learn from the past but also doesn’t enforce their own rules.

  2. perdajz March 19, 2015 at 8:47 pm

    The lesson is that if you shut down a nuclear plant it will be replaced by something dirtier and more dangerous. Plug that into your event trees and fault trees.

    • joy cash March 20, 2015 at 1:13 pm

      There is nothing “dirtier” than literally thousands of years of nuclear waste. Ask Chernobyl or Fukushima victims.
      Solar, wind, wind, hydro are our future. Creating far more living wage jobs, as well.

  3. joy cash March 19, 2015 at 11:52 am

    All nuclear plants leak radiation & create tons of raidioactive waste, for which we have yet to come up with a clear resolution. 60 yrs. is enough to learn this is an experiment gone very wrong. Chernobyl & Fukushima are just 2 examples of unending aftermath of our species arrogance in science. One caused by human error, one caused by nature’s laws. And yet we continue down this path of self destruction, deluding ourselves that we are in control. Facts speak for themselves, we are not in control. And to the extent we continue our folly nuclear path, we will reap what fools we be.

  4. Skeptical Observer March 19, 2015 at 8:03 am

    PPB, the problem with your analogy is, with the EPA there are forests, cows and ecosystems that are not in compliance with some of their hare-brained restrictions! NRC lives in the REAL world! If you would prefer to live in the ‘cold and dark’ I’m sure there are 3rd and 4th world countries that would love to have you.

    • Public Pit Bull March 19, 2015 at 11:06 am

      You make a good point SO. I think the EPA has over-regulated in some cases. But isn’t overregulation better than under regulation? Isn’t the public better served by erring on the side of safety?! I do not discount the fact that nuclear plants currently provide around 20% of our nation’s electricity on a 24/7 basis. They are indeed part of the backbone of our nation’s vital electric grid. But we can and should wean ourselves from nuclear power for a whole host of reasons, public safety first and foremost.
      Another indicator for me that the EPA is erring on the side of public safety is the fact that I constantly hear about how God-awful the EPA is; that they are just unreasonable; that they don’t bend on enforcing regulations. The nuclear industry rarely bitches about anything the NRC does. Don’t you find that somewhat ironic?! Also if the EPA doesn’t do its job the consequences aren’t nearly as grave as the NRC not doing its job. For example, existing nuclear power plant accident PREVENTION should be the top priority. However, the NRC is seriously considering allowing the nuclear industry to just better MITIGATE a Fukushima-type accident here and NOT PREVENT one here in the US?! Would you have supported just mitigating another Three Mile Island accident here years ago?! High time to phase out nuclear power. Certainly no new nuclear plants, no license extensions for existing plants, and much tougher enforcement by the NRC of existing regulations.

      • perdajz March 19, 2015 at 8:55 pm

        Do you think the NRC has a way or preventing earthquakes and tsunamis? Nothing happened at Fukushima. It is trivial as an industrial accident. If you disagree, it’s only because you are not familiar with industrial accidents.

        The existing regulations are absurdly over-conservative for the nuclear power industry.They are based on little more than hysteria and superstition. The shame is that other more dangerous forms of electricity generation, which would be everything except nuclear power, benefit from comparatively lax regulation and media disinterest in actual accidents.

      • joy cash March 20, 2015 at 3:15 pm

        My point exactly, we have had decades of industrial accidents. Only ones that leave behind literally hundreds/thousands of years of clean up efforts & human/environmental devastation are nuclear accidents. “Human error” is a known factor, nature’s unpredictably is known factor.
        If a solar system blows, clean up is relatively harmless when compared to any neclear accident.

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