Major Study: Reactor No. 5 releases may explain why so much radioactive xenon detected… or “recriticality has occurred in one of the reactor units”

Published: October 28th, 2011 at 11:25 am ET
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SOURCE: Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant, Stohl, A., Seibert, P., Wotawa, G., Arnold, D., Burkhart, J. F., Eckhardt, S., Tapia, C., Vargas, A., and Yasunari, T. J., October 20, 2011

“Fortunately, due to the maintenance outage and the survival of one diesel generator, it seems that unit 5 reactor cores as well as spent fuel ponds have not suffered major fuel damage,” says the study.

Though, Reactor No. 5 is mentioned again several pages later:

“Total a posteriori [experienced levels] 133Xe emissions are 16.7 EBq, one third more than the a priori value [predicted levels] of 12.6 EBq (which is equal to the estimated inventory) and 2.5 times the estimated Chernobyl source term of 6.5 EBq.”

If there was only 12.6 EBq of xenon-133 inventory that could be emitted from reactors 1-3 and spent fuel pool No. 4 — yet 16.7 EBq was experienced — where did the extra xenon come from, according to the study?

  • There is the possibility of additional releases from unit 5.”
  • Another possibility is that recriticality has occurred in one of the reactor units.

The study says the a priori emissions could have been overestimated, but discounts the notion that the initial 12.6 EBq figure so poorly underestimated the amount of xenon in Reactors 1-3 and SFP 4, “It is unlikely that the 133Xe inventories of the reactor units 1–3 were one third higher than estimated.”

ABSTRACT: ACPD – Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant: determination of the source term, atmospheric dispersion, and deposition

SOURCE: Discussion Paper

See also: Report: Fukushima Reactors No. 5, 6 now in crisis — Cesium outside release points up 1,000% in recent days — Local says Hitachi engineers coming to help (VIDEO)


Published: October 28th, 2011 at 11:25 am ET
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16 comments

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  2. NYT on Recriticality: Japan nuclear prof. says chain reaction at Fukushima can’t be ruled out — Disagrees with expert in America who says it’s unlikely December 14, 2011
  3. Fukushima Reactor Designer: Meltdowns would have likely occurred WITHOUT tsunami — A serious investigation on horizon? -NYT January 16, 2012
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16 comments to Major Study: Reactor No. 5 releases may explain why so much radioactive xenon detected… or “recriticality has occurred in one of the reactor units”

  • radegan

    “Another possibility is that recriticality has occurred in one of the reactor units.”

    There’s your nugget of truth buried under several paragraphs of horsepoop.


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  • PoorDaddy PoorDaddy

    Sheeee-it! Fire number 5 back up!
    Whats a little more xenon and cesium among friends?
    Once you get the dial maxed out on your detection equipment, the whole world is your oyster.


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  • Cindy

    Did you guys see this ?

    If birds are dropping dead, people would have gone first …

    Its a radiation lethal dose chart for man and animals … man goes first , LOL

    http://www.nuc.berkeley.edu/neutronics/todd/dose.html


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    • hanaloa hanaloa

      Cindy, I just canʻt find the humor in this:

      “Its a radiation lethal dose chart for man and animals … man goes first , LOL”

      As I review your posts I am concerned that you are suggesting that the radiation isnʻt a concern, that we are simply and comically exaggerating the dangers. I welcome and even yearn for healthy skepticism– I shared many of the same thoughts as you when first observing the “fog” coming from Reactor 3 (Report: “Abnormal Smoke from Reactor 2″ 10/27/11 1116 EDT). But you seem adamant in debunking the concern.

      Furthermore, I wish you gave more background on this chart you posted for us. What is the scientific basis for this data. It seems like a rhetorical question, but I have to ask, what is your intention for posting this. These charts do nothing to allay my concern over mounting die-offs.


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    • Anthony Anthony

      Birds started dropping dead beginning months of 11… thousands of them, across species, across the globe. All of a sudden and grouped together.

      Millions of fishes also perished. All of a sudden, all at once, across the species, all around the world. All of a sudden and grouped together with themselves.

      And the Birds.

      Then Fukushima.

      Now.


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  • Bobby1

    “possibility that re-criticality has occured…”

    Huh? They based their whole analysis on CTBTO isotope data. Didn’t they see the iodine graphs from their own dataset?

    http://www.bfs.de/de/ion/imis/ctbto_aktivitaetskonzentrationen_jod.gif

    MAYBE there was re-criticality?


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  • pure water

    I remain on my previous opinion, that this report is blatantly and stupidly censored! I wish I knew exactly how! See just this:
    “reactor cores” and then “reactor 5″. Reactor 6 just disappearing! But someone has left plural for cores.
    If I am wrong with the linguistics, please, correct me.


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  • nuckelchen nuckelchen

    but we don’T lives at babel.
    we got translators and ex-skf today.

    it takes me wonder how tepco plays out informations like here.
    like some kind of a joker-card.

    and more and more i become a picture of something constructed.
    japanese false flag to get of their atomic debris.


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  • Hot Tuna Hot Tuna

    Meanwhile, R1 cooking at 413 sv/hr today. This won’t go on for the next 10,000 years, right?

    http://atmc.jp/plant/rad/?n=1


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  • nono, see, it was 496 3 days ago, so now it is going down, a clear sign


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  • Hot Tuna Hot Tuna

    I still want to know what they’re doing with that little crane in front of R1. Maybe drill down to the corium? Then what? Plug the steam fissures with concrete?


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