Mainichi: Location of melted fuel unclear — Why test for xenon when neutron detectors can directly indicate criticality?

Published: November 3rd, 2011 at 8:07 am ET
By
Email Article Email Article
17 comments


Nov. 3 — Excerpts and highlights of today’s editorial in Mainichi: Closer monitoring and more explanation of Fukushima reactors needed

  • “Xenon was detected in the containment vessel of the plant’s No. 2 reactor, and the finding was confirmed by the semi-governmental Japan Atomic Energy Agency”
  • “The finding suggests that nuclear fission is occurring in the reactor”
  • “The government and TEPCO need to find out why the fission has occurred and take appropriate responses”
  • “The possibility that it might reach criticality has surely caused anxiety to the public”
  • “At least one expert says it would be no surprise if nuclear fission has been occurring since well before these latest findings”
  • “The gas inside the containment vessels of the Fukushima plant’s No. 1 and 3 reactors has not yet been analyzed”
  • “Officials should consider equipment that can detect neutrons, as they can be used as a direct indicator of whether criticality has occurred”
  • “The discovery of xenon in the No. 2 reactor’s containment vessel suggests nuclear fission is occurring even though the temperature at the bottom of the pressure vessel is thought to be below 100 degrees Celsius — It raises questions as to whether such a reactor can be considered stable, even if it is under that temperature threshold”
  • “The conditions and locations of melted fuel in the plant’s No. 1 to 3 reactors as well as the details of the damage to the reactors remain unclear”
Published: November 3rd, 2011 at 8:07 am ET
By
Email Article Email Article
17 comments

Related Posts

  1. Mainichi: “It remains unclear where the melted fuel is situated” — “Temperatures of the pressure vessels alone are far from convincing” September 21, 2011
  2. Mainichi: Melted nuclear fuel seems to be leaking out from reactor buildings November 14, 2011
  3. Mainichi: “The melted nuclear fuel is sinking toward water under the ground” June 27, 2011
  4. AP: Nuclear fuel moved as it melted — Little known about location and condition of reactor cores — Limited info on spent fuel pools December 9, 2011
  5. Top Japan Official: There have been various discussions on location of melted fuel — We ‘think’ we are able to cool fuel inside primary containers and pressure vessels November 19, 2011

17 comments to Mainichi: Location of melted fuel unclear — Why test for xenon when neutron detectors can directly indicate criticality?

  • Flapdoodle Flapdoodle

    My take on this is TEPCO has only been interested in the temperature so that they can claim it is in cold shutdown if it reads below 100 degrees C. regardless of what is being emitted.


    Report comment

  • watcher watcher

    In the reactor? or under?


    Report comment

  • watcher watcher

    Is occurring? or continues to occur?


    Report comment

  • Bleifrei Bleifrei

    Not real ..:
    the reactor is cool
    suprice the danger melt is gone “head-scratching” where ever ´
    but the reactor is cool !

    nuklide outside is from anyone ,tepco don´t now !
    come on JP GOV your the boss and its yours “PAY NOW”!
    (people like This are worse than any other ..
    make me sick

    My conscience tells me :go to clean and reload the pumpgun


    Report comment

  • Steven Steven

    So, tons of active nuclear fuel that needs to be kept separated and continuously cooled with large amounts of water (which incidentally heats up so much it turns to steam) goes AWOL and ends up in some sort of blob on/under the floor. Is anyone really suggesting that somehow criticality has stopped? That if you mix it all up together it cools down and goes to sleep?

    Is there not some sort of intelligence test for people entering the nuclear industry?


    Report comment

    • NoPrevarication NoPrevarication

      @Steven

      “Is there not some sort of intelligence test for people entering the nuclear industry?”

      Clearly there is such a test. In order to pass it, once must test out as being of subnormal intelligence.


      Report comment

      • StillJill StillJill

        NoPrevarication,…they often look for something NOT intelligence.
        They look for character weakness, hubris, ability to be cruel and detached,…..they sure don’t want ANY *spirit*!

        I’ve worked for three county’s,…in their Mental Health departments, with much public speaking demands. When I choose NOT to join the Union after my 6 month probationary was drawing to an end,…they let me go. Another time I would not falsify ‘delivery of service hours’,…they let me go,….Cali is an ‘at will hire’ state. They can fire you for any little whim they may get,….and they don’t even have to tell you why.

        To be clear,….If you have integrity,….are a truth teller,….you will not advance,…you will have (people) trying to ruin you, CONSTANTLY.


        Report comment

    • pure water

      Steven,
      They seems to have gone some sort of mind shift. I have heard enough from several of them, who were normal in the past. About bananas, about radon, about flights, about sleeping next to other person, about things being done the best possible way in Japan… What bothers me is they repeat one and the same things, like they can not find any argument of their own.Or may be they expect sudden quantum escape of coriums to another dimension.


      Report comment

  • dosdos dosdos

    “Officials should consider equipment that can detect neutrons, as they can be used as a direct indicator of whether criticality has occurred.”

    Then they’d have report the figures, which they do not want to do. It would cost TEPCO and the government more money.


    Report comment

  • dosdos dosdos

    From shill central….

    http://www.world-nuclear-news.org/RS_Fukushima_xenon_from_spontaneous_decay_0311111.html

    “Tepco said it considered the source of the xenon to be spontaneous fission on those grounds that it had injected boric acid to the reactor vessel to reduce the likelihood of chain fission reactions but was still able to detect xenon. Temperature and pressure data from the unit also showed no change around the time of the xenon’s discovery in another indication that chain reactions were not taking place.”

    Either as they explain, or the boron is not reaching the fission in progress under the reactor.


    Report comment

    • pure water

      Well, we have met the expression critical mass, and some of the fuel is still there. Especially in reactor 2


      Report comment

    • jimbojamesiv

      So, what you’re saying, DosDos, is that similar to, I believe, the movie, The China Syndrome, the officials are claiming that the gauges never moved so there couldn’t have been anything going on untoward because the gauges would have told us so, but, unlike the movie where the officials were simply lying, in Fuku, the reason the gauges haven’t changed is because the fuel rods, or now the pile of goo, are no longer in the reactor and I wonder exactly how far deep beneath the reactor, causing the gauges to have reported no changes?

      Is that really what’s going here?


      Report comment