Photo/Illutration A device grabs melted fuel debris at the bottom of the Fukushima No. 1 nuclear power plant’s No. 2 reactor. (Provided by Tokyo Electric Power Co.)

Tokyo Electric Power Co. announced on April 17 that it had collected a sample of melted nuclear fuel from the No. 2 reactor at the crippled Fukushima No. 1 nuclear power plant, using an extraction device.

This was the second trial removal of fuel debris from the reactor's containment vessel, with the extraction coming from closer to the center of the structure than the first time.

The debris will be pulled out of the containment drywell and retrieved for analysis at a research facility in Ibaraki Prefecture.

The removal work began on April 15.

According to TEPCO, on April 17, the tip of the “fishing rod-type” device was lowered to the bottom of the containment vessel, and a few millimeters of yellowish pebble-shaped debris were lifted out.

The debris was about 1 to 2 meters closer to the center of the containment vessel than where a sample was first removed in November 2024, and there was more debris around the area than the last time.

Over the next few days, the device will be pulled out of the containment drywell, and after checking the radiation levels of the debris, it will be placed in a special container for safety.

The total debris in the nuclear plant’s No. 1, No. 2 and No. 3 reactors, where the core meltdowns occurred, is estimated at 880 tons.

In November, TEPCO collected 0.7 gram for the first time since the accident occurred in March 2011, following the Great East Japan Earthquake and tsunami. 

By increasing the number of samples and the areas they are collected from, TEPCO hopes to get a clearer picture of the current harsh conditions inside the reactors, where the debris must be removed before decommissioning. 

(This article was written by Fumi Yada and Yusuke Ogawa.)

Related News