nuclear-news

Little progress seen in removing fuel debris at Fukushima plant

By RYO SASAKI/ Staff Writer,  https://www.asahi.com/ajw/articles/14854929, March 6, 2023

Tokyo Electric Power Co. has little to show in removing fuel debris at its Fukushima No. 1 nuclear power plant in the 12 years since the nuclear disaster started.

The company, in fact, has postponed the work.

An estimated 880 tons of fuel debris remain in the No. 1, 2 and 3 nuclear reactors at the plant.

Remote-control operations must be used to remove the fuel debris because radiation levels in the reactor buildings could kill a person within one hour.

TEPCO had initially planned to start removing fuel debris at the No. 2 reactor, where the level of radiation is comparatively low, by the end of 2022.

However, the company announced in August 2022 that it had abandoned this target, citing delays in developing a robotic arm that could be used to remove the debris.

The company set a new target to start the removal work in the second half of fiscal 2023.

The government and TEPCO aim to complete the decommissioning of the stricken plant between 2041 and 2051.

However, the company’s first goal is to test the retrieval of only several grams of fuel debris. It still hasn’t decided how it will conduct larger-scale removal.

TEPCO has also not explained when it will start removing fuel debris at the No. 1 and No. 3 reactors.

A “submergence method” is under consideration to remove fuel debris from the No. 3 nuclear reactor, but it’s still unclear whether it will be implemented.

With the submergence method, workers would cover the building that houses the No. 3 reactor with a metal structure, fill the inside of the structure with water to submerge the reactor, and then remove fuel debris from the upper part of the building.

Another worrying factor about the Fukushima nuclear power plant is that the foundation, or “pedestal,” supporting the No. 1 reactor’s pressure vessel has deteriorated so much that the reinforcing bars are now exposed.

Concerns have been expressed about the earthquake resistance of the pedestal.

March 6, 2023 - Posted by Christina Macpherson | Fukushima continuing, wastes