TEPCO to Remove Debris from Fukushima Nuclear Power Plant Wed. at Earliest; 2nd Sample Clears Radiation Level for Safety Standards

The Yomiuri Shimbun

14:33 JST, April 22, 2025

A second sample of nuclear fuel debris will be removed from the Fukushima No. 1 nuclear power plant No. 2 reactor on Wednesday at the earliest, Tokyo Electric Power Company Holdings, Inc. announced Monday.

TEPCO on the day of the announcement measured the radiation level of the sample, which is in a metal space outside the plant’s No. 2 reactor containment vessel, and confirmed a reading of 0.1 millisieverts per hour, well below the limit of 24 millisieverts per hour stipulated in the safety standards for removing such debris.

Taking into account the health risks faced by workers exposed to radiation at the plant, the company’s policy is to only retrieve small pieces of debris so that the radiation levels remain below the safety standard limit.

A trial removal operation, the second of its kind at the plant, began on April 15. On Thursday, a cable connected to a fishing rod-like device had a claw attached to the end of it. By adjusting the length and angle of the device, workers maneuvered the claw to grab a piece of debris located near the bottom center of the containment vessel.

In November last year, another piece of debris was retrieved during the first trial removal operation. The sample retrieved on Thursday lay 1-2 meters away the sample retrieved in the first trial.

If all goes smoothly, TEPCO will complete the removal by Wednesday. The sample will be put into a specialized container and transported to a lab in Ibaraki Prefecture run by the Japan Atomic Energy Agency, where its composition and hardness will be analyzed. It will also be compared to the sample removed from the site after the first trial to enable a better understanding of conditions inside the reactor.