Former NRC chairman not confident in San Onofre restart or risk assessment based on probabilities

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Jaczko at California Discussions

Former chairman of the Nuclear Regulatory Commission Gregory Jaczko spoke at a meeting in San Diego today about the future of nuclear energy as a member of an expert panel which included former Japanese Prime Minister Naoto Kan, Fairewinds Chief Engineer Arnie Gundersen, and former NRC commissioner Peter Bradford.

Jaczko said his thinking about the role of regulatory decision-making evolved during and after the Fukushima Daiichi accident.  It is the very nature of dealing with nuclear power plants to be forced to deal with unlikely situations which can yield unearthly economic consequences.  During his tenure with the NRC in response to the Fukushima Daiichi nuclear disaster, Jaczko was continually questioning NRC staff why they had not considered these things beforehand.  He shared at the meeting how he was repeatedly told that the probability of these events were not deemed very high and therefore was not considered likely and that at the time regulators couldn’t justify the expenditure of manpower and resources.


“It’s a fairly novel idea to allow a plant to operate at a reduced power level because of a safety issue. When you’re operating at reduced power levels, it indicates a lack of confidences and raises a lot of questions.”

Former NRC Chairman Gregory Jaczko on the proposed restart of San Onofre Unit 2


The public was warned that they must pay closer attention to the consequences of a severe accident, for though no one can predict what will happen, it is now known through experience that the consequences can be tremendous.  Jaczko shared a personal story which took place after he resigned as commissioner of the NRC.  Jaczko traveled to Japan and met with a grandmother and grandfather who had been evacuated from near Fukushima Daiichi.  The couple had showed Jaczko pictures of their children and grandchildren.  Before they evacuated they had lived in the same village as their family but after the accident they were now all spread out.    It reminded him of the importance of family.  “These are among the people most affected by the accident,” he said, “We must prevent this from happening in an absolute way.”

The former commissioner also questioned the risk analysis tools used to guide the approach taken by the industry to mitigate the dire consequences of nuclear accidents.  Over the years, Jackzo explained, the NRC began to rely more and more on probability to address issues of concern, but there are many issues which are difficult to put into numbers, which has lead to a lot of resistance to addressing these problems.  Clearly, the accident at Fukushima Daiichi showed the world that low-probability events can occur, and that both the regulatory bodies around the world and the societies which make up different nations must consider the costs of severe accidents themselves.

Nuclear power plants can be shutdown, but they cannot just be turned off.  When a plant loses electric power for an extended period of time, what is known as a station black-out event, it will almost always lead to a large release of radiation.  While experts have known this for a long time, what was missing was an appreciation that it could happen.  He urged attendees to remember that accidents do happen, the very definition of accident being ‘something which will happen’, and that the Nuclear Regulatory Commission needs to take another hard look at what can happen when things go wrong.

Jaczko said the proposed restart by Southern California Edison has raised doubts about the nuclear facilities operations, “It’s a fairly novel idea to allow a plant to operate at a reduced power level because of a safety issue. When you’re operating at reduced power levels, it indicates a lack of confidences and raises a lot of questions.”

Jaczko ended his discussion with a plea for the United States adding, “It is time we reconsider prolonging the life of the aging nuclear fleet in the United States.”  He urged the public to acknowledge that it is time they tap into the true courage inherently inside of all people and face these issues.  He said that he has always been amazed by the courage of the human spirit to overcome obstacles and tragedies in all forms and sizes and to address the future in a mature and resilient manner.

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  1. As I see it: The trouble with evaluating risk is what funds are available to support the costs to make plants safe, at some point it will be to hell with any more costs lets build the plant with the amount of safety we can afford. From my under standing of 3/11 is that after getting a order to build the plants they soon found out that the fixed price turnkey project was way way to low, they had to reduce costs to keep from losing to much. They reduced the the location by many feet in height from sea level which reduced the pump size required saving many dollars at the risk of small tsunami swamping the plant. They used above ground pumps instead of submersible pumps that work under water and can not be destroyed by being flooded(I believe all plants are using these above ground pumps even Fort Calhoun!). They either ignored the fact that earth quacks and tsunami occurred near their site with in 100 years before or did not do any research as people in the area had grandfathers who died in the tsunamis. They must have known that by reducing the site by removing the soil put the plant almost in the ground water, this has to be a concern if a plant has a melt down, it is easier to poison the surrounding area and more or impossible to get under the plant like at Chernobyl. If they hadn’t removed the soil it surly would have been a stable site against the earth quacks that jiggle the water saturated soil. It went on with many more compromises. I have wondered if a construction compromise is dune at one plant, is it sited by other plant builders to be used at another plant because it is of like kind even though it was a compromise at the original plant use. Or does this infuse through time as fewer people know why compromises where made so OK the requests, this happens in many industry that is growing for a long time.

  2. There is a terrible understanding throughout of statistical risk, probability, and the models from which the numbers are gleaned. It’s just that simple. The fact that they’re running the models at all implies risk, doesn’t it? While the math wizardry is well known, need one point out our ever-present and perpetual flaw of hubris? Is that ever considered in any model? If not, it surely ought to be. Just the exclusion of that one item (hubris) in the model should give one to question what else wasn’t considered.

    Personally, I’m getting pretty sick with the prevalence of what is misunderstood as science, especially in the sphere of the general public. What we have here is not science, but technology, two totatlly different things that may be mutually dependent, but they are more like fraternal twins. Misapplication of technology in science leads to failed experiment; misapplied science in technology can lead to quite a bit worse, it seems.

  3. Here is a note to those in leadership roles in particular, who have constantly lambasted us for raising concerns about San Onofre when we were not qualified to do so. I hope they will heed their own advice now and “leave it to the experts”. They should stop listening to Edison as if they were something more than a reliable source of income for the community. The stakes are too high to ignore the message from those who have lived the nightmare of a nuclear disaster. For people who want to do the responsible thing, please sign our petition to Keep San Onofre Shut Down now.

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