Coolant water is leaking to the next turbine building of reactor1

In the roadmap that Tepco released on 9/24/2012, Tepco reported coolant water injected into PCV and RPV is leaking from the North-East side of the reactor building through the access hole.
The leaked contaminated water is presumed to flow into the next turbine building.

Coolant water is leaking to the next turbine building of reactor1

Tepco presumes injected coolant water is leaking from the crippled PCV and RPV to flow out of the reactor building. In order to identify the leaking point, they attempted to measure the water levels of four corners of the basement floor in reactor building, where torus room is located on 9/20/2012.
Because of the high level of radiation, they only measured it at the two corners of the floor, North-East corner and North-West corner of the floor. From the investigation, they found the water level is 50cm deeper in North-West corner to suggest the water is leaking out of the reactor building from North-East corner.
From the water retaining in North-East corner, they measured 4.1E+10 Bq/m3 of Cs-134 and 7.4E+10 Bq/m3 of Cs-137.

Source 1 2



Français :

L’eau de refroidissement fuit dans le bâtiment de la turbine voisine du réacteur 1

Dans la feuille de route que Tepco a publiée le 24 septembre 2012, Tepco rapportait que l’eau de refroidissement injectée dans la PCV (= Enceinte de confinement primaire) et la RPV (= Enceinte pressurisée)  fuit par le Nord-Est du bâtiment à travers le trou qu’ils ont fait pour y entrer. (…)
L’eau contaminée de la fuite est supposée se répandre dans le bâtiment de la turbine voisine.

L'eau de refroidissement fuit dans le bâtiment de la turbine voisine du réacteur 1

Tepco suppose que l’eau de refroidissement injectée fuit des PCV et RPV ravagées pour s’écouler hors du bâtiment du réacteur. Afin d’identifier le point de la fuite, le 20 septembre 2012, ils ont tenté de mesurer les niveaux de l’eau aux quatre coins du rez-de-chaussée du bâtiment du réacteur où se trouve la salle du tore.
A cause du haut niveau de radioactivité, ils ne l’ont mesuré qu’en 2 des 4 coins, au NE et au NW de l’étage. De ces investigations ils ont établi que le niveau de l’eau est plus profond de 50 cm à l’angle NW suggérant ainsi que l’eau fuit hors du réacteur par l’angle NE.
Dans l’eau retenue du coin NE, ils ont relevé 4,1 E+10 Bq/m3 de Cs-134 et 7,4 E+10 Bq/m3 de Cs-137.
(ndt : E+10 = 10 000 000 000 = 10 milliards)

Sources : 1 2

  1. Those numbers are so high as to be hard to comprehend. And its likely also flowing into the ocean there as well. Does anyone have a recent saltwater sample/test results from the waters off Fukushima? Test for radiation of course..all possible nuclides..I131, C-134/137, PU..and the rest…has anyone fessed up? We know the US Carrier, Ronald Reagan, got a strong dose just after 3/11..and a few tests released for the waters by various governments..but no long term testing that I know of. Hope someone has the data..somewhere.

  2. is that measure BQ/M3 or BQ/CM3, i would be surprised if it’s 41 BQ/M3 as that’s only a low level rad dose,
    but the other would be very intense but not crazy compared to many of the other numbers we’ve seen

    1. Watch out, the number is given as 4.1E+10 Bq/m3.
      The E stands for *10^, so you have to read it as 4,1*10^10 Bq/m³.

  3. The becquerels are expressed in exponential notation, so 41000000000 Bq/m^3 of Cs-134 and 74000000000 Bq/m^3 of Cs-137. More compactly, 41 GBq/m^3 and 74 GBq/m^3 respectively.

    From the releases regarding the steel dropped in the spent fuel pool we could read its activity around 2500 Bq/cm^3 and 4000 Bq/cm^3. Now there’s a million cm^3 in a m^3 (100*100*100) so those numbers come out to 2.5 GBq/m^3 and 4.0 GBq/m^3.

    I did a quick calculation then and figured that radioactivity might account for most of the 200mSv/h reported above the pool; if so then it’s reasonable to expect about 4Sv/h over the water in the containment. This would lead directly to death in about a hour, so certainly wouldn’t want to be in the pants of people making those measurements, even though they’re insulated from the water by a wall. Water is also a good moderator medium in itself, if this stuff dried out it would be fatal in many ways.

    There’s quite a huge difference between those figures, almost 20x times in the containment compared to the spent fuel pool, but not large enough to suspect there’s any unit confusion at play here. It does, however, support the contention that the water in the containment is in direct connection to the melted, recently active core, and the fuel rods in the SFP3 may not have experienced recent criticality. Of course total amount of water and amount of material undergoing fission play huge role here and I doubt anybody knows either for sure.

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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.


September 2012