Breaking News: Possibility of recriticality again

Radioactive Iodine was measured in Gunma and Tokyo again. Officials announce the reason is unknown.

In Gunma, 4 ~ 10 Bq/kg of radioactive Iodine were measured at 3 sewage-treatment plants.
The samples were taken from 11/21~12/1/2011.
The sewage-treatment plants are in Tamamura cho, Kiryu, and Hiratsuka.
29 ~ 68 Bq/kg of Cesium were also measured at 5 sewage-treatment plants in Gunma.

Also, Iodine 131 were measured from incineration ash of garbage disposal facilities in Tokyo.


350 Bq/kg from Kita garbage disposal facility (11/9/2011)

28 Bq/kg from Suginami garbage disposal facilities (11/7/2011)

15 Bq/kg from Shin koto garbage disposal facilities (11/11/2011)

None of the official announcement has been published as always.


震災ファイル:3下水処理場の汚泥から放射性ヨウ素 /群馬
毎日新聞 12月11日(日)11時18分配信


  1. Along with many other people who follow the situation, I was slow in realizing that re-criticality keeps happening. I don’t think I completely understood it before late summer.

    Now one question which no one seems to have attempted to answer is how many re-criticalities we’ve gone through. Perhaps it’s a tall order, because we have at least? about? at most? 4 meltdowns, and no-one can agree even on that.

    As an academic, I know that people engage in all kinds of assumptions and conclusions. I also know that science is actually not neutral; it’s highly subjective. It’s usually used for military and financial purposes, and often twisted in its official presentation accordingly.

    But I am amazed at how no one has even tried to guess, based on the presence of elements with a very short half-life. Is re-criticality occurring once every two months now?

    1. theoretically recriticality happens when the cooling does not reach all the nuclear material, there is a bit more to it but that is it basically. with the material molten into clumps obviously the water does not reach every place, so recriticality on a minor scale happens many times a day. i haven’t been following fuku since months because it depressed me to see all the denial and accompliscence, but by that time we had covered that.
      for what i know recriticallity’s would not be admitted (weird because it stands out) let alone announced, as allowing a further erosion of trust in tepco and jap gov, but also ncr and western governments in with the deal.
      tepco never made the processes inside the reactors as insightfull as to allow an estimate or apprehension of the scale of releases, it means the figures are on the not so positive side. for recriticallity i would say that is an indication not of the nr of events (1000s or so per molten core at least) as much as of the scale of those. a bigger event would more probably cause a further release of significant isotopes. that they don’t tell about it when every indication is there thus probably means there are rather big events, wich, could be confirmed by iodine.
      probably the somewhat bigger ones would be simple to observe from within the plant due to pressure , sound and perhaps even light effects as well as irregular releases of extra steam, vapours, gasses or smokes, because of sudden differences in pressure. it’s just they want to announce things like ‘cool down’ cold shut down’, not: radiation still very hot.

  2. Well of course there is still nuclear fission going on at Fukushima Daiichi. The plant is still polluting the enviroment with radionuclides. The big easter egg for next year will be, where the melted nuclear fuel in the 3 reactors is. Lets keep the fingers crossed that there wont be a nuclear volcanic explosion until then!
    I am not a geologist but it would be interesting to know on which geological formation the plan is sitting on, in order to predict any China Syndrome effects?
    Guessing from the near location to the ocean the ground water (water table) must be 10 to 15 meters deep?
    Does anybody have any infos on that topic?

    1. yes, that is known or at least was so in march and april.
      it sits on a (small) granite cell, one of the very hardest and not that deep.(not as good as it seems, the cell is small and it’s context geologically active, but not as bad as it could be).

      melt downs into the crust , what i think you mean with china syndrome, do not appear to happen as projected in the years 50-60. (basically water and perhaps the burning of soil/rock, does not keep the mess ‘compact’ but disperses it enough that it does not smelt into the crust very rapidly or deeply, alltho perhaps there is an element of secrecy in play once more)

      some of the core appeared to have reached the groundwater , (that i think is at 6 (-8) mtr , but forgive me if i remember that incorrectly. ) at least some transuranids eufemistically also called ‘iodine, cesium, etc’ and ‘corium’ entered the groundwater by the end of april at a rate that could not be explained by leaking suppression pools only.

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About this site

This website updates the latest news about the Fukushima nuclear plant and also archives the past news from 2011. Because it's always updated and added live, articles, categories and the tags are not necessarily fitted in the latest format.
I am the writer of this website. About page remains in 2014. This is because my memory about 311 was clearer than now, 2023, and I think it can have a historical value. Now I'm living in Romania with 3 cats as an independent data scientist.
Actually, nothing has progressed in the plant since 2011. We still don't even know what is going on inside. They must keep cooling the crippled reactors by water, but additionally groundwater keeps flowing into the reactor buildings from the broken parts. This is why highly contaminated water is always produced more than it can circulate. Tepco is planning to officially discharge this water to the Pacific but Tritium is still remaining in it. They dilute this with seawater so that it is legally safe, but scientifically the same amount of radioactive tritium is contained. They say it is safe to discharge, but none of them have drunk it.


December 2011