TOKYO (Kyodo) -- The head of the International Atomic Energy Agency said Thursday that Japan should be flexible on its timeline for removing melted fuel from the wreckage of the Fukushima Daiichi nuclear power plant, with safety the top priority.
The government and Tokyo Electric Power Company Holdings Inc., currently plan to begin extracting the highly radioactive debris by the end of 2021, though the process is expected to be fraught with technical challenges.
"The issue of the timing is always important...but it's not a race against time. It is a race, I would say, more against safety. And more safety, this is what is very important," IAEA Director General Rafael Grossi told reporters in Tokyo a day after visiting the crippled plant.
The work of removing the fuel from the three reactors that suffered meltdowns triggered by a powerful earthquake and tsunami in March 2011 will begin with the No. 2 unit, which did not suffer a hydrogen explosion, according to the government's latest decommissioning road map.
Grossi said a more pressing issue is what to do with water that has been contaminated with radioactive materials as it is either pumped into the wreckage to cool the melted fuel or runs underground.
The contaminated water, which is increasing by about 170 tons per day, is being treated using a so-called advanced liquid processing system, or ALPS, that removes most radioactive materials other than tritium before being stored in tanks on the plant's premises.
But space is expected to run out by summer 2022 and the government is considering ways to dispose of the water including releasing it into the Pacific Ocean and evaporating it.
Grossi said the IAEA is reviewing a subcommittee report on the plans, though he added that both methods were in line with international practice.
He stressed that monitoring by IAEA inspectors would help assuage the concerns of local fishermen and neighboring South Korea, both of which have voiced strong opposition to releasing the water into the environment.
"Not that Japan needs it, because the scientific capabilities are there, but I think it's very different when you have a third party -- the IAEA -- there providing an impartial, technical, dispassionate reading of what is going on. This is what we bring to the table."
On stalled denuclearization talks involving North Korea, Grossi said U.S. Secretary of State Mike Pompeo had assured him during a recent trip to Washington that a deal could still be reached and asked for IAEA inspectors to be prepared to enter the country.
Both North Korea and the United States have remained quiet after Pyongyang's year-end deadline for progress in negotiations passed without a breakthrough.
Grossi, an Argentine diplomat who succeeded the late Yukiya Amano as IAEA director general in December, is on a five-day visit to Japan, during which he has met with Prime Minister Shinzo Abe. On Thursday he held talks with industry minister Hiroshi Kajiyama and Toyoshi Fuketa, chairman of the Nuclear Regulation Authority.