Safety violations at Diablo Canyon nuclear plant

May 31, 2011

On April 26, Nuclear Regulatory Commission staff did a safety inspection at the Diablo Canyon nuclear power plant, as part of NRC inspections of all U.S. reactors that were triggered by the Fukushima Daiichi nuclear plant disaster in Japan. [NewYorkTimes]

Even though the NRC’s inspection report did not flag PG&E for a serious violation of the rules, it did list more than a half-dozen issues that could jeopardize the plant if it were confronted with the kind of chain reaction of unexpected disasters that struck the Fukushima nuclear complex.

The NRC investigators reported:

•    The plant had a single diesel-driven pump to provide emergency cooling water to a single reactor in case an earthquake cut off normal water flow. The pump could not have serviced both of the plant’s reactors if they lost normal water supply simultaneously, the NRC staff said.

•    Some doors at the plant required to protect against flooding of major safety equipment would not self-latch as required. One latch was “degraded,” they said.

•    The plant’s six emergency diesel generators were located in the same plant area, and thus vulnerable to a “common mode” failure.

•    An earthquake could cause a structural failure in the building where the fire truck is stored, and debris could block crews from using the truck.

•    PG&E planned for a contractor to provide seawater for emergency cooling, but had no backup plan if an earthquake and tsunami blocked highways to the plant. PG&E intended to rely on the California National Guard to deliver diesel fuel for emergency generators if roads were impassable, but had no memorandum of understanding in place for the deliveries.

•    Four 20-foot extension cables, used to operate fans that cool portable generators, were missing from their storage location.

PG&E spokesman Paul Flake told the New York Times issues reported by the NRC had been identified by the company’s own review after Fukushima, and an inspection by the Institute for Nuclear Power Operations, the industry’s confidential safety monitor. “All of the issues identified in the [NRC] inspection report are being addressed. We continue to work with the NRC to introduce safety improvements” required to protect the plant, he said.




  1. amusselm says:

    Anybody got a link to the NRC report itself? This statement confuses me:

    The plant had a single diesel-driven pump to provide emergency cooling water to a single reactor in case an earthquake cut off normal water flow. The pump could not have serviced both of the plant’s reactors if they lost normal water supply simultaneously, the NRC staff said.

    Is that a single pump for the entire plant, or a single pump per reactor that only has enough output to service the reactor its attached to? Does that mean that there is no other backup system for emergency core cooling? I can’t believe that PG&E would risk $2 billion in reactor cores like that.

    (0) 0 Total Votes - 0 up - 0 down
  2. willie says:

    I heard Germany has decided to shut down all of its nuclear power plant within a year or two and will NOT even consider building new safer Thorium typel plants.
    If this is true, I would not say they are thinking ahead of us (in terms of advancing technology) but rather surendering to a more simple life (environmentally friendly).

    On this issue, if the proverbial one hit, we would be in the same shit as Japan, and manual labor would be required (human sacrafice – its always been the case) to regain control cooling off the fuel rods (robots won’t solve the the emergency).

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    • willie says:

      If this is all true
      If the proverbial BIG ONE does hit us
      (Maybe I should say “when” instead of “if”
      Then we are all in deep booboo, just like Japan
      Because the Ricter Scale as I understand it, is 40 times greater intensity from 7 (major damage) to 8 (major to total damage).

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  3. ApathyWillKillYou says:

    Does anyone remember Pacific Gas and Electric Co.’s unsuccessful, $46 million attempt to pass Proposition 16 last summer?

    46 million might buy another back up diesel-driven pump to provide emergency cooling water.

    And they planned on getting the diesel fuel from the National Guard only they forgot to tell the National Guard!

    Bottom line… if the back up cooling is needed from auxillary diesel pumps and back up electrical generators then the proverbial sh*t has hit the fan!

    And how LONG do you think it will take for that one brave official to declare a county wide emergency evacuation in case of a severe radiation leak…. well I hope it happens at night because we will all be glowing in the darek by then!

    (2) 2 Total Votes - 2 up - 0 down
  4. bobfromsanluis says:

    I for one would like to know how much of this information was known by the plant manager when he was on the Dave Congalton Show touting how “safe” Diablo Canyon is. Is the management of the plant simply devious in not disclosing these incidents or inept in not realizing these shortcomings were happening? Either way, the “bottom line” for most corporations is to protect their company from any perceived safety violations and I don’t trust the management at all.

    (4) 10 Total Votes - 7 up - 3 down
    • willie says:

      If you think this something, what do you think about the bull on the “Smart Meter” alledgely having null effects on human tissues and organs?

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  5. MaryMalone says:

    What do they mean, “…did not flag PG&E for a serious violation of the rules…”?

    Having one diesel generator which can only service one reactor, when there are two on site, isn’t “serious”?

    Having malfunctioning doors that are in place to save important safety equipment from flooding…that’s not “serious”?

    Having all of the emergency backup generators stored in one area isn’t “serious”?

    If there was a good-sized earthquake and one of the faults underlying Diablo ruptured, resulting in blocking of the one access road to Diablo, critical damage to buildings where safety/emergency equipment, or any of the kinds of damage one can see in a big earthquake–that could lead to a Fukushimaesque situation.

    I’m shocked. How Diablo’s management could play fast and loose with the lives of the considerable number of people who would experience radiation should a big earthquake hit, is completely beyond me.

    (6) 20 Total Votes - 13 up - 7 down
    • R.Hodin says:

      Sounds like the NRCs reasoning goes like this:

      a) There’s a design flaw in the safety systems that would be an issue if the plant suffered a catastrophic event such as Fukushima.

      b) The NRC never required plant safety design for anything even remotely as serious or complex as the Fukushima catastrophe

      c) Diablo isn’t currently suffering a catastrophic event such as Fukushima.

      d) The design flaw is not a serious issue.

      e) Everything is under control, go home now.

      (8) 10 Total Votes - 9 up - 1 down
  6. Typoqueen says:

    Holy Cr@p! Shut it down now! Each one of these issues are big and everyone should be concerned.

    (0) 32 Total Votes - 16 up - 16 down
    • choprzrul says:


      With all of that leaking radiation, I’m not sure how anyone down wind is surviving…..

      (14) 16 Total Votes - 15 up - 1 down
      • Typoqueen says:

        I didn’t see anything about leaking radiation in this article. Is that what has to happen, do we have to have a leak before something gets done?

        When we have something that has the power to damage as much as this plant has then every thing had better be in top working order, no fudging on safety no second best. We are talking about a nuke plant on an active earthquake fault which shouldn’t have built there in the first place.

        (0) 12 Total Votes - 6 up - 6 down
        • r0y says:

          I’ll go out on a limb and guess choprzul was being facetious regarding the “OMG! D000000m!” comments.

          Not that I trust the government any more than PG&E for my safety, what I’d like to see is the most profiting individuals and their families to live within 20 miles or so of the plant. Their motivation for safety *might* then be taken seriously.

          (3) 7 Total Votes - 5 up - 2 down
          • Typoqueen says:

            I knew chop was being sarcastic,,,so was I. I like your idea regarding the families living close to the plant.

            (2) 4 Total Votes - 3 up - 1 down

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