It’s unclear whether Fukushima nuclear disaster cleanup in Japan can be finished, as planned, by 2051

TOKYO — Too little is known about melted fuel inside damaged reactors at Japan’s wrecked Fukushima nuclear power plant, even a decade after the disaster, to be able to tell whether its decommissioning can be finished, as planned, by 2051, a U.N. nuclear agency official says.

“I don’t know, and I don’t know if anybody knows,” Christophe Xerri, head of an International Atomic Energy Agency team reviewing the plant’s cleanup progress, said Friday.

A massive earthquake and a tsunami in March 2011 destroyed cooling systems at the Fukushima plant in northeastern Japan, triggering meltdowns in three reactors. It was the worst nuclear disaster since the 1986 Chernobyl accident.

Japanese government and utility officials say they hope to finish its decommissioning within 30 years, though some experts say that’s overly optimistic and that a full decommissioning might not even be possible.

The biggest challenge: removing and managing highly radioactive fuel debris from the three damaged reactors, according to Xerri, director of IAEA’s Division of Nuclear Fuel Cycle and Waste Technology.

“We need to gather more information on the fuel debris and more experience on the retrieval of the fuel debris to know if the plan can be completed as expected in the next 30 years,” he told reporters.

The cleanup plan depends on how the melted fuel needs to be handled for long-term storage and management, he said.

The IAEA team’s review, the fifth since the disaster, was mostly conducted online due to the coronavirus pandemic. Only Xerri and another team member visited the plant before compiling and submitting a report to Japan’s government on Friday.

The team noted progress in a number of areas since its last review in 2018, including the removal of spent fuel from a storage pool at one of the damaged reactors as well as a Japanese government plan, adopted this past week, to start discharging massive amounts of treated, though still radioactive, water that’s accumulated at the wrecked plant into the Pacific Oean in 2023.

It hopes to win support for the plan from fishermen and others.

Research and development of new technologies needed for the cleanup will take one or two decades, Xerri said.

Government officials and plant operator Tokyo Electric Power Company Holdings haven’t provided a clear picture of how the plant will look when the cleanup ends.