7,200,000,000 Bq of All β nuclides in contaminated water leaked from Reactor 2

On 11/5/2015, Tepco announced the retained water in Reactor 2 building was found leaking on transferring.

From Tepco’s report, the leaked volume was approx. 0.23 m3. The leakage detector went off at 0:09 of the day.

The leaked water is assumed to be the coolant water leaked from the reactor 2 vessel and groundwater flowing into the plant building.


In total, 7,200,000,000 Bq of all β nuclides to include Strontium-90 and 3,037,500,000 Bq of Cs-134/137 are reported to have leaked out. The density of other nuclides was not announced.

Tepco is still investigating the exact leakage point. However, it is highly likely that the transferring pipe was damaged and it was made of Polyethylene.






Français :

Le réacteur 2 fuit du liquide pour 7,2 milliards de Bq de radioactivité β


Le 5 novembre 2015, Tepco annonce avoir découvert une fuite des eaux du bâtiment du réacteur 2 pendant un transvasement.

Selon le rapport de Tepco, le volume de la fuite est d’environ 0,23 m³. Le détecteur de fuite s’est déclenché à 0:09 ce jour-là.
L’eau de la fuite est supposée être du liquide de refroidissement échappé de l’enceinte du réacteur 2 mélangé aux eaux souterraines inondant le bâtiment.

Au total, 7,2 milliards de Bq de radioactivité β, dont du strontium 90, et 3 037 500 000 (> 3 millions de) Bq de radioactivité au césium 134/137 sont rapportés avoir fuit. Pour les autres nucléides la radioactivité n’est pas communiquée.
Tepco recherche encore l’endroit exact de la fuite. Néanmoins, il est hautement probable qu’un tuyau de transvasement soit endommagé attendu qu’ils sont surtout en polyéthylène.


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.


November 2015