A national agency that is considering technical policies for the full-scale removal of fuel debris, which is said to be the biggest hurdle in the decommissioning of the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Station, It turns out that they have begun to consider a new method of covering the entire building with a huge structure, filling the interior with water, and taking it out.
At the Fukushima Daiichi Nuclear Power Plant, it is estimated that the so-called "fuel debris", which is a mixture of surrounding structures and nuclear fuel that melted down to the bottom of the reactors and containment vessels of Units 1 to 3 that caused the "meltdown," 880 tons are accumulated.
TEPCO is aiming to start a trial retrieval using a robot arm at Unit 2 in the second half of next fiscal year, but a full-scale retrieval method has not yet been decided.
Regarding this, it is known that the government's specialized organization "Nuclear Damage Compensation and Decommissioning Facilitation Corporation" has newly begun to consider a method of covering the entire building with a nuclear reactor with a huge structure and filling the inside with water and taking it out. I was.
By shielding the radiation with water, it is possible to reduce the radiation exposure of workers, and it is also expected to have the effect of preventing the scattering of radioactive materials.
However, detailed technical studies are yet to be carried out, and the feasibility is uncertain at this time.
Regarding the retrieval of "fuel debris", a method of filling the containment vessel with water had been considered until now, but it was abandoned due to the need to close the hole left by the accident and the risk of radiation exposure to workers. , was being investigated, focusing on how to take it out without filling it with water.