The Japanese gov considers completely submerging reactor 3 in a tank to remove molten fuel debris

Photo: Fuel Handling Machine in Reactor 3. (8. 2015) [Link]


In order to remove the molten nuclear fuel (debris) from the Fukushima Nuclear Plant, TEPCO is considering a “submersion method” in which the entire reactor building is submerged in water. In this newly proposed method, the entire reactor building is enclosed in a structure like a huge water tank.

However this has not been implemented in the nuclear industry so far, thus, technical and cost issues remain uncertain. A person concerned pointed out that this is going to prolong the decommissioning process even longer and substantially affect the cost, which is currently estimated to be over 56 billion USD.

This new construction method uses a structure called a “hull structure” that is normally used to build ships and airplanes and is resistant to pressure and maintains durability. The entire reactor building, including the basement, will be enclosed to retain water inside, and debris will be removed from the top of the structure. This method is assumed to be applied to the worst damaged facility, reactor 3.

At the Fukushima nuclear plant, another plan that is to submerge only the primary containment vessel (PCV) was initially considered, however it was postponed due to the difficulty of repairing the severely damaged vessel as it will increase the radiation exposure of workers.

Regarding reactor 2, Tepco is currently planning to remove the molten fuel debris in the atmosphere.

Debris removal is the most difficult task in decommissioning the Fukushima nuclear plant. It is estimated that the total amount of debris from reactor 1 to 3 is approximately 880 tonnes. TEPCO and the national government plan to remove debris and complete decommissioning by 2051.



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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 2022