Tepco admits 400,000,000 Bq of All β leaked to the sea / Radiation level jumped over double in seawater

Following up this article.. 7,230,000 Bq/m3 of all β nuclide leaked from drain to the sea / “Contamination level suddenly jumped up” [URL]


On 3/4/2015, Tepco announced they estimate approx. 420,000,000 Bq of All β nuclides (including Strontium-90) leaked to Fukushima plant port due to the leakage accident.

This is merely based on Tepco’s own assumption.


The report was submitted to NRA (Nuclear Regulation Authority). The report and mass media state “approx. 400,000,000 Bq of All β nuclides leaked to the sea”, however actually about 44,000 Bq/m3 of All β nuclides have been constantly detected from the drain water flowing to the sea since before the leakage accident. 420,000,000 Bq is only the increased amount from the usual leakage level.


About 6 days after the leakage accident, All β nuclide density largely jumped up near the exit of the port, which was from 15,000 Bq/m3 to  24,000 Bq/m3.

Near the center of the port, it jumped up over double, which was from 24,000 Bq/m3 to 64,000 Bq/m3 as well. Half of the entire water in the port is assumed to go to the Pacific daily.

Most likely the whole leaked contamination flowed to the Pacific within 3 days after the accident.


Tepco states the cause has not been identified yet.







Français :

Tepco reconnaît que 400 millions de Bq de radioactivité β ont fuit en mer : la radioactivité a plus que doublé dans l’eau de mer


Article lié : Une radioactivité β de 7,23 millions de Bq/m³ s’est écoulée en mer par une évacuation : “La radioactivité est brutalement montée”

Le 4 mars 2015, Tepco annonce qu’ils estiment à environ 420 000 000 Bq (420 millions) de radioactivité β (dont du strontium 90) la fuite dans le port de la centrale de Fukushima à cause de l’accident.
C’est seulement basé sur les propres hypothèses de Tepco.

Le rapport a été remis à la NRA (Nuclear Regulation Authority). Ce rapport et la grande presse parlent de “environ 400 000 000 Bq de radioactivité β partis à la mer”, cependant, avant l’accident de cette fuite, on a en réalité constamment relevé environ 44 000 Bq/m³ de radioactivité β dans les eaux de l’évacuation s’écoulant à la mer. 420 000 000 Bq ne représentent que l’augmentation au-dessus du niveau habituel des fuites.

Environ 6 jours après la fuite, la radioactivité β a grandement augmenté à la sortie du port, soit de 15 000 Bq/m³ à 24,000 Bq/m³.
Près du centre du port, ça a aussi augmenté de plus du double, soit de 24 000 Bq/m³ à 64 000 Bq/m3. On considère que, par jour, environ la moitié de l’eau du port s’écoule dans le Pacifique.
Il y a toutes les chances pour que toutes les eaux extrêmement radioactives soient parties dans le Pacifique dans les trois jours qui ont suivi l’accident.

Tepco affirme que l’origine de la fuite n’a pas encore été trouvée.


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.


March 2015