TOKYO: Tokyo Electric Power Company Holdings Inc. said Thursday that it has completed the trial removal of nuclear fuel debris from a crippled reactor at its Fukushima No. 1 nuclear power plant in northeastern Japan.

In the two-month trial, TEPCO collected a 5-millimeter piece of fuel debris from the No. 2 reactor at the plant and placed it in a special container for transport after confirming that radiation levels were not problematic for carrying out the operation.

It is the first time that such debris has been collected from a reactor containment vessel since the plant was hit by the March 2011 massive earthquake and tsunami.

The project to decommission the disaster-stricken nuclear plant has now entered a new phase. The debris piece will be analyzed at four facilities, including those of the Japan Atomic Energy Agency in Ibaraki Prefecture, and the findings are expected to be used for the full-scale removal of fuel debris.

TEPCO began the trial work in September and collected the debris piece from the reactor containment vessel’s bottom on Oct. 30 with a remote controlled device shaped like a fishing rod. The device with the debris piece was removed from the containment vessel on Saturday.

A total of about 880 tons of nuclear debris, a mixture of melted fuel and reactor parts, is believed to remain in the Fukushima plant’s No. 1 to No. 3 reactors.

Due to extremely high radiation levels and unknown conditions, removing the debris from the reactors is considered the most difficult part of the Fukushima plant decommissioning project.

The trial removal was originally planned for 2021, but was delayed for about three years due to the development of necessary devices overseas and other preparations.

When the trial removal was about to begin in August this year, an error was found in the order of the pipes attached to the retrieval device. Even after the trial began in September, it was suspended due to a camera glitch.

According to a schedule drawn up by the government and TEPCO, the trial debris removal is at the beginning of the third and final stage of the decommissioning project, which they aim to complete by 2051.

JIJI Press