Debris Removal from Fukushima Nuclear Plant to Be Postponed Again; 7 Treated Water Discharges Planned for Fiscal ’24

Yomiuri Shimbun file photo
Robotic arm unveiled last July in Fukushima Prefecture

Tokyo Electric Power Company Holdings Inc. will postpone the start of its nuclear fuel debris removal at the No. 2 reactor of the crippled Fukushima No. 1 nuclear power plant from by the end of fiscal 2023 to around October 2024, it announced Thursday.

This will be the third time the firm has postponed the start of the removal work.

According to TEPCO, it began removing sediment blocking the insertion slot for a robotic arm to go inside the containment vessel in January, but this work is expected to take longer than expected, causing the removal of nuclear fuel debris to be delayed.

The Yomiuri Shimbun

To speed up the process, a fishing rod-type device will be used instead of the robotic arm as it can be inserted even into narrow gaps. TEPCO must seek the Nuclear Regulation Authority’s approval for any changes to the equipment, which could take as long as six months. The company said this would not affect the target decommissioning period of between 2041 and 2051.

The debris is a solidified mixture of nuclear fuel that melted in the reactor core meltdown and structural materials inside the reactors. There is believed to be a total of about 880 tons of debris in the Nos. 1-3 reactors. The original plan was to remove a few grams in 2021 on a trial basis, but the plan has been postponed twice so far due to the coronavirus pandemic and a malfunction of the robot arm.

TEPCO has also announced that it would discharge a total of 54,600 tons of treated water into the ocean in seven installments in fiscal 2024, with the amount of water discharged per installment to be about the same as those in fiscal 2023. So far, no impact on seawater or fish has been confirmed.