Contaminated water still contains 2,600 ~ 4,700 Bq/m3 of Sr-90 even after ALPS

According to NRA (Nuclear Regulation Authority), contaminated retained water of Fukushima plant still contains 2.6 ~ 4.7 Bq/L of Strontium-90 even after purified by ALPS (Advanced Liquid Processing System) based on their basic trial test of ALPS.

The water contains 16000000 ~ 120000000 Bq/L of Strontium-90 before purification.

The report is unclear in a couple of points.

1. The contaminated water is supposed to contain 11000000 ~ 51000000 Bq/L of Strontium-89. However, the half-life of Sr-89 is only 51 days. Is it still produced from nuclear fission ??

2. Alpha nuclides, such as Pu-238, 239, 240, Am-241, 242, 243, Cm-242, 243, 244 are not shown the amount. They are all summed up in “Gross alpha nuclides”. (0.46 ~16 Bq/L in unpurified water, less than 0.066 Bq/L after ALPS.) How much of each alpha nuclide is contained in the retained water ?

3. Why is reproduction of this report of NRA prohibited ? Isn’t it a public document ?


Related article..Tepco started propaganda to downplay the risk of Tritium for discharging contaminated water to the sea [URL]




Français :

Les eaux contaminées contiennent toujours entre 2 600 et 4,700 Bq/m³ de Sr 90 même après ALPS


Selon la NRA (Nuclear Regulation Authority), les eaux contaminées retenues à la centrale de Fukushima contiennent toujours 2,6 à 4,7 Bq/L de Strontium 90 même après passage dans le purificateur ALPS (Advanced Liquid Processing System), ceci sur la base de leurs tests d’essais de ALPS.

L’eau contient de 16 000 000 à 120 000 000 Bq/L de Strontium 90 avant sa purification.

Ce rapport n’est pas clair sur quelques points :

1. L’eau contaminée est supposée être entre 11 000 000 et 51 000 000 Bq/L en Strontium 89. Or, la période du Sr 89 n’est que de 51 jours. Est-ce qu’il est issu d’une fission nucléaire en cours ??

2. Les quantités des nucléides alpha, genre Pu 238, 239, 240, Am 241, 242, 243, Cm 242, 243, 244 ne sont pas communiquées. Tout est regroupé sous “Ensemble des nucléides alpha”. (0,46 à 16 Bq/L dans les eaux non filtrées, moins de 0,066 Bq/L après ALPS). Quelle est la répartition des nucléides alpha dans les eaux stockées ?

3. Pourquoi la reproduction de ce rapport de la NRA est-elle interdite ? N’est-ce pas un document public ?

Article lié : En préparation du rejet des eaux contaminées dans l’océan, Tepco lance une propagande de minimisation des risques liés au tritium

Source :

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.