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Japans NP again

  1. Jul 18, 2007 #1


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    http://www.bloomberg.com/apps/news?pid=20601101&sid=a8qFB6xPyJyk&refer=japan [Broken]

    Japan Nuclear Plant, World's Biggest, May Be on Fault (Update1)

    By Megumi Yamanaka and Jason Clenfield

    July 18 (Bloomberg) -- The world's biggest nuclear power station, located in central Japan, may be on a seismic fault that shifted in a magnitude 6.8 earthquake this week, causing a radioactive leak into the ocean.

    Reports by Japan's weather bureau suggest ``a fault line runs under the plant grounds,'' owned by Tokyo Electric Power Co., Akira Fukushima, deputy director-general for safety examinations at the nuclear and industrial safety agency, told reporters in Tokyo today.

    The Kashiwazaki-Kariwa plant was not designed to withstand an earthquake as powerful as the one that killed nine people in Niigata prefecture July 16, nor does the facility meet the trade ministry's new earthquake standards put in place last year, Fukushima said.
    Last edited by a moderator: May 3, 2017
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  3. Jul 18, 2007 #2


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    That's scary. Why wouldn't they do a geological survey before building a nuclear plant (or any power plant...no matter your source of energy, you don't want the whole plant going down in case of an earthquake) and put it in a different location rather than on a fault line? What's the likelihood of missing a fault line during a geological survey and only realizing it's there after an earthquake? (That's a real question, not a rhetorical one...I don't know if there are factors that would make it possible to honestly miss the presence of a fault line.)

    Or, are there truly no other options in Japan as places for putting a plant?

    I haven't seen any updated reports on the leak, but at least according to the first day's reports, it really was minor. I know people panic when they hear radioactive leak, but there is natural radioactivity all around us, and if it's being quickly diluted into the ocean, it may not be much of a concern at all as long as they stopped it from continuing. In a way, it actually speaks more to the safety of the plant that it withstood such an earthquake, sustained the type of damage it did, and did NOT have a catastrophic failure.

    It seems a little odd to be expecting it to meet brand new earthquake standards though. Even if there is a requirement to retrofit to meet the new standards, that's not likely to be something that could be accomplished in less than a year unless they were already very close to meeting those standards.
  4. Jul 18, 2007 #3


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    The article does a good job of putting the leak into perspective - we'll have to wait and see, though, what the later reports say about the actual magnitude and failure mode.

    I think the point of bringing up the new earthquake resistance standards is to imply that the standards should have been tougher previously. That may be true.
  5. Jul 18, 2007 #4


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    I can't think of any country that has taken earthquake resistance as seriously as Japan.
  6. Jul 18, 2007 #5
    And yet, they built a reactor on a fault line. Yikes.
  7. Jul 18, 2007 #6


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    Pretty much the whole country is a fault linem, as silly as rebuilding San Francisco in the same place.

    In the past they tried alternative ways of securing acess to nearby fuel reserves but that also caused quite a bit of trouble.
  8. Jul 18, 2007 #7
    The malfunctions and a delay in reporting them fueled concerns about the safety of Japan’s 55 nuclear reactors, which have suffered a string of accidents and cover-ups. Nuclear power plants around Japan were ordered to conduct inspections.


    So it's not that they take earthquake resistance more seriously than the rest of the world, it's just that they cover it up more?
  9. Jul 18, 2007 #8


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    They would and they are required to do so. But they could have missed a particular fault, especially if it had been inactive. On the other hand, I don't know the details of TEPCO's geo-survey's. Seismic analysis is part of plant design and qualification.

    Here is the historic seismic activity map from USGS
    Note the star, which corresponds to the 6.6 mag earthquake of July 16.

    http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2007ewac.php#details [Broken]
    http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2007ewac.php#maps [Broken]

    Today I read that the Kashiwazaki_Kariwa NPP has been shutdown indefinitely, and I imagine that some managers will be dismissed. It is troublesome with the spills of contaminated material and malfunctions.

    First KK unit went online in 1985, and they just continued building at the site. They really do not have a lot of options to build elsewhere in Japan.
    Last edited by a moderator: May 3, 2017
  10. Jul 19, 2007 #9
    Inspectors reportedly identified four fault lines in the area while conducting a geological survey before work began on the Kashiwazaki plant in 1980 but concluded that they were inactive, according to the Asahi newspaper.

    The Citizen's Nuclear Information Centre said that the fault believed to have triggered the earthquake was not discovered during pre-construction surveys. "Clearly Japan's earthquake safety standards are inadequate," it said in a statement.


    The scary part here is that no one else takes this stuff more seriously than they do.
  11. Jul 19, 2007 #10


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    The US and Europeans take nuclear energy pretty seriously.

    I get involved in some matters, and believe me - we take it very seriously - and that just adds to the stress.

    Nuclear Plant Safety at Issue After Japan Quake
  12. Jul 19, 2007 #11
    But FredGarvin was focused on earthquake resistance. Do the US and Europeans take it more or less seriously than the Japanese? My impression at the moment is that Japan doesn't take it all that seriously, and if Fred is right, we're in deep trouble here.
  13. Jul 19, 2007 #12


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    Seismic analysis is an important part of ensuring the structural integrity of a nuclear system, and the core and primary system, and the containment and auxilliary structures are built to certain standards in order to ensure that the public is protected against the consequences of an accident.

    For new plants, particularly in the US and Europe, not only do they have to meet strict seismic codes, but we now have to ensure that heavy commercial aircraft fully loaded with fuel will not penetrate containment or auxilliary building, and will not compromise the integrity of the core or any spent fuel storage systems.

    There are some considerations here with respect to the KK NPP:

    1. They very well could have missed an inactive fault. Presumably an investigation will shed some light on that.

    2. There are many systems supply the nuclear plant that are not necessarily built to the same critical standards as the core/primary and containment systems. We'll have to wait for a final report on the plant's response and the various malfunctions. That so many malfunctions occurred is worrisome.

    3. As with any human-based system, there are 'human factors' involved, and one of those could be complacency, which the industry has to struggle with all the time.

    We'll just have to wait for the report and findings.
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