Fukushima radioactive water to be released into sea after UN gives approval

International Atomic Energy Agency chief delivers results of its safety review during Japan visit

A Buddhist monk in Seoul protests against Japan's plan to release radioactive water from the Fukushima plant into the sea. AP

Japan’s plans to release treated radioactive water from the Fukushima nuclear power plant into the sea meet UN nuclear agency safety standards, the body said on Tuesday.

International Atomic Energy Agency director-general Rafael Grossi delivered the results of a two-year safety review to Japan's Prime Minister Fumio Kishida at the start of a four-day visit to the country.

The 1.3 million cubic metres of water – enough to fill 500 Olympic-sized swimming pools – was used to cool fuel rods at the Fukushima plant after it was damaged by the earthquake and tsunami in 2011.

It will take 30 to 40 years to release, pending official approval from the national nuclear regulatory body for Tokyo Electric Power.

Japan has not specified a start date for the plan, which was conceived in 2021.

The report comes despite fierce resistance from China and other neighbouring countries concerned about the threat to the marine environment and public health.

Fishing unions say the approval will undo work to repair their reputations after several countries banned Japanese seafood products following the 2011 disaster.

“We will continue to explain the safety of the plan to release the treated water into the ocean to the international community, based on scientific evidence and with transparency,” Japanese Foreign Minister Yoshimasa Hayashi said at a joint briefing with Mr Grossi.

A Tokyo Electric Power Company employee explains the plan to release treated radioactive water from the Fukushima nuclear power plant. AP

China called for the water release plan to be suspended. Ahead of the report's release, Beijing on Tuesday said the agency's report cannot be a “pass” for the scheme.

Japan maintains the process is safe as it has treated the water.

The water has been filtered to remove most radioactive elements except for tritium, an isotope of hydrogen that is difficult to separate from water.

The treated water will be diluted to well below internationally approved levels of tritium before being released into the Pacific Ocean.

Japanese officials told foreign journalists in China last month that the tritium levels in the treated water were lower than that found in waste water regularly released by nuclear plants around the world, including in China.

Explanation ignored

The officials said they had made many repeated attempts to explain the science behind Tokyo's stance to Beijing, but that its offers had been ignored.

China on Tuesday said Japan's comparison of the tritium levels in the treated water and waste water was “completely confusing concepts and misleading public opinion.”

Mr Grossi will visit the Fukushima plant on Wednesday.

After his Japan trip, he will head to South Korea, where consumers have been stockpiling sea salt and seafood ahead of the water release.

He is also expected to visit New Zealand and the Cook Islands in a bid to ease concerns over the plan, according to media reports.