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.

Author: Moderator

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

24 thoughts on “Continuing to Learn the Lessons of San Onofre”

  1. 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. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. MikeMcpuck
    No question in my mind that you are right. The plant response to the initiating event demonstrated that San Onofre was well equiped to prevent this difficult technical problem from introducing even the tinyiest risk to the community, and the initial approach for restarting this valuable zero-CO2 energy producer in Southern California had an over abundance of conservative measures to protect the public safety interest. There are no technically competent arguements to the contrary, including within the NRC.
    Edison was being paid a marginal return on the operating costs for this $4 Billion plus investement from me and other ratepayers. Given the choice between pandering to incompetent politicians and self proclaimed nuclear ‘experts’ for fraction of the yearly San Onofre operating costs, or abandoning my $4 Billion investemen in favor of selling me another $4 Billion CO2 pumping generator while gaining access to yet another $4 Billion plus Decommissioning Piñata, what responsible Board of Directors would ever walk away from an opportunity like that?
    No, the NRC failed to be decisive with information they fully understood for supporting restart, and set the stage for the sleeping California Public Utilities Commission to step in and protect the public from the only real threat in this whole sad story. I blame the CPUC for not protecting me and my environment.

  8. 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.

  9. This is my “Ode to Joy”. (:-) Very good comments! I think that the real culprit is indeed the nuclear industry. Through their mouth-piece and lobbyist, the Nuclear Energy Institute (NEI) they line the pockets of congressional reps who “oversee” the NRC. The NRC is thereby really “captured” by a God-awful nuclear industry who is only interested in perpetuating their own selfish interests.

  10. 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.

  11. What is the extent of this dysfunctional performance?
    What is the causation of the extent?

  12. For decades San Onofre held very bad safety records. Only when it became very public did NRC step up, after Senators asked for criminal investigation. Now ex-head of Cal PUC is under investigation. The entire nuclear energy industry is a dying dinosaur in it’s death throes. Clean renewables are out pacing nuclear hazardous energy. We are left with what to do with 60 yrs. of highly toxic waste.
    It’s a tragic story of our contemporary times. Not enough proper oversight of Big corporate endeavors.

  13. Rebecca Sigmon – I suggest that you and your team begin by reviewing all the statements submitted to the NRC (which also includes your Office) about the Inspector General investigation (which was in itself was a white wash) into the San Onofre AIT Report .

    At least one Ph.D. now retired NRC Senior nuclear engineering expert has submitted documentation describing our current situation, where the NRC no longer has the in-house capability to analyze replacement steam generators designs and now must depend upon Utilities to submit plans that they and their sub-contractors have “verified” as being workable! Said another way, the Utilities are now self approving their own designs which then the NRC accepts and then approves as meeting NRC guidelines. This practice is not acceptable!

    If nothing else, San Onofre proved that Utilities are focused on making profits and that includes bringing to market replacements that allow them to keep their downtime to a minimum. SCE came so very close to causing a nuclear incident(619) accident because they figured that they could self design something that their own engineers had no business designing, especially since it would not be reviewed by either the NRC or the public for compliance!

    Here is a January 2012 industry article from Nuclear Engineering International by Boguslaw Olech and Tomoyuki Inouetwo, two engineers (one from SCE and one from MHI) where they “brag” about all the things they did without having to submit to a full 50.59 process. It is interesting to note that the RSGs for San Onofre Unit 3 failed the same month this was published:

    Improving like- for-like RSGs
    https://s3.amazonaws.com/s3.documentcloud.org/documents/347889/col-nrc-tech-paper.pdf

    SCE installed Unit 2 and ran it conservatively until it was due for a scheduled fuel replacement at just about the same time they fired up Unit 3 and pushed it over the stated limitations because they thought everything was OK with their design. They had no idea that these new replacement steam generators had more internal damage that all the rest of the US Nuclear fleet combined. https://sanonofresafety.files.wordpress.com/2011/11/steamgeneratortubesplugged1.pdf

    I wish you well and suggest that you reach out to those that have submitted papers to the NRC about San Onofre, since they can best help you to prevent another San Onofre multi-billion dollar safety debacle!

  14. Good point 7.
    What concerns me that with the EPA, for example, if you can’t comply and can’t afford to get into compliance you go out of business. With the NRC they simply relax the rules for the nuke industry.

  15. I have a technical question for Rebecca Sigmon. I do understand SONGS committed to return to 70% (with later S/D for tests) in their response to the CAL, maybe voluntarily. When I read the NRC document at the “reviews” link above, and specifically page 21 of the PDF, I note in RAI 32 that NRC simply asked a question. SONGS didn’t even attempt to answer it? They just asked for a license amendment instead! Wow, shows a total lack of understanding of design bases, TSs and TS bases, TS Action Statements and SR Tests and SR intervals, etc. and how it all fits together.
    When asked how “their” plan would demonstrate structural integrity performance criterion in Technical Specifications (TS) 5.5.2.11.b.1 at 100%, they simply should have said “like we and everybody else always does. We’ll go to 100% and run the appropriate STs for SG & RCS leakage; when that passes we’ll back down to 70%. That’s all any ST can do; a snap shot operability. But that would demonstrate functional integrity at 100% power. They had a time-at-high-power related problem, not an inability to prove integrity at 100% power. U2 ran a whole cycle and never sprung a leak. The whole TS package fits together as an integral process just for this reason, stuff can fail after passing tests. It’s like any plant that ever sprung a SG tube leak has invalidated their “proof of integrity” done earlier? I don’t think so, and never was the intent of the whole TS package.
    Would NRC have balked at such a justification, and it so specifically why?
    But of course that approach would require SONGS (and NRC) to both be absolutely convinced there was no problem at 70%. If they didn’t believe that, they never should have proposed it in the first place.

  16. Nonsense from NRC. I live about 10 miles from San Onofre and following the events. It’s my observation that NRC regs and actions gave the owners all the excuse they needed to shutdown two reliable reactors that only needed a single steam-generator fix.

  17. I have the best plan. It is called switch to Wind and Solar. I have a patent on a new type of Wind Energy Called WindJammer Generators which will be built by WindJammer Energy. They cost much less per unit than a Nuclear Power Plant and will make Nuclear Power obsolete. No one can predict every possible event that could destroy a Nuke in the blink of an eye. On one has developed a solution for the Indefinite Spent Fuel Storage Problem which will be a 250,000 nightmare for future generations. WindJammer Generators are Eco Friendly to People, Birds and Wildlife and can be installed in Big Cities or everywhere electricity is needed.

  18. It’s a pretty sad and limited viewpoint that holds that you can only improve processes if they are ineffective.

  19. You say that “The review also finds that the staff properly used a Confirmatory Action Letter as an oversight tool in responding to the San Onofre events.”

    However, going down that unnecessary and unmandated path led directly to the loss of non-carbon generating capacity in California. The Confirmatory Action process was effectively used to stop a safe plant from ever restarting. So my question is, while you were holding yourselves blameless for this destructive Confirmatory Action process, what alternatives did you consider that might have been used instead?

  20. Sad that the NRC is so conflicted. Let’s see…protect the public or the nuclear industry???? Really no choice at all-the survival instinct favors a bloated federal agency over anything else. Kill the cow and there goes the milk!

  21. Outside whatever issue, this steam generator incident could’ve and has occurred in other type power plants. It’s NOT unique nor related to nuclear and should not be willfully construed as such to the unwashed. End of facts.

  22. This is your oxymoron statement of the year NRC: “…17 actions to enhance what are already effective tools for overseeing US operating reactors.” If these tools are already effective why bother enhancing them?! Also how do you know existing tools are already effective in overseeing US operating reactors? On the contrary, sir, your oversight activities are flawed as numerous commenters have noted. Furthermore NRC, you can enhance away as long you don’t cost nuclear plants one dime. The NRC does not want to hurt, in any way, nuclear plant competitiveness. The NRC does not want to look a gift horse in the mouth. For example the NRC is seriously considering letting the nuke industry off the hook on the lessons learned after the Fukushima accident. They do not want to force the industry to actually do stuff to prevent a Fukushima-type accident here as it would be costly for the industry to do so. Instead of requiring appropriate design changes to our nuke plants to prevent such an accident, the NRC wants the industry to be able to better handle the consequences of such an accident when it occurs! In effect lets let the cow out of the barn but come up with a means to more quickly chase it down. How sad that the NRC would even be considering such a thing. Isn’t the primary responsibility of the NRC to protect the public?!

Comments are closed.