Editorial: Halt of debris extraction attempt at Fukushima plant a fiasco fueling anxiety

Tokyo Electric Power Company Holdings Inc. (TEPCO) has suspended procedures to extract fuel debris at the No. 2 reactor of the disaster-stricken Fukushima Daiichi nuclear power plant at the preparation stage. The reactor holds approximately 237 metric tons of metal and nuclear fuel debris generated in the core meltdowns triggered by the March 2011 Great East Japan Earthquake and tsunami.

It turned out that five pipes to be used in inserting a debris retrieval device into the reactor were connected in the wrong order. While the pipes were in place at the site for about a month, apparently no one noticed the mistake. The work was left up to a company cooperating with TEPCO.

One cannot help but be disappointed at such a rudimentary error. TEPCO is urged to elucidate the cause and prevent a recurrence, taking every precaution in the plant decommissioning work.

While TEPCO acknowledged that it was an “elementary mistake,” it is beyond comprehension just why the utility has made such a blunder. Even minor mistakes could lead to major trouble. The Fukushima Prefectural Government lodged a protest with senior TEPCO officials, saying the fiasco “could cause anxiety among prefectural residents.”

TEPCO must take the situation seriously and examine whether there were any flaws in its operation manuals and checking systems.

In addition to the No. 2 reactor, the No. 1 and 3 reactors also hold fuel debris that accumulated following their meltdowns, estimated to total about 880 tons. The debris removal is considered the centerpiece of the decommissioning work, and is critical in entering the final phase of the three-stage reactor dismantling process.

Unless the utility can reduce the debris that still emits extremely high doses of radiation and keeps humans away, it is impossible to curb the generation of contaminated water and mitigate the risks of workers’ radiation exposure during decommissioning work.

If only around 3 grams of debris, or about an “earpick-full” of the material, can be extracted from the No. 2 unit as planned, it is expected that the elements and property of the debris can be closely examined, making it a foothold for full-scale debris retrieval.

While TEPCO had planned to commence the debris extraction process in 2021, it was pushed back by three years due to challenges it faced in developing the retrieval device among other factors.

TEPCO said it will not resume the process until the cause of the mishap is unraveled, while maintaining that the fiasco “will not affect” its plan to complete decommissioning by 2051. However, there is no guarantee the process will be trouble-free in the future, and we cannot stay optimistic.

The revival of Fukushima Prefecture cannot be foreseen without the removal of fuel debris. TEPCO must draw a lesson from the latest problem and use it to lead to the steady implementation of reactor decommissioning.