Photo: Koji Ito / The Yomiuri Shimbun via AFP)
The International Atomic Energy Agency says Japan's approach to discharge treated nuclear wastewater into the Pacific is consistent with relevant international safety standards.
The Tokyo Electric Power Company (TEPCO) is preparing to dump about 1.3 million tonnes of contaminated water into the Pacific over three to four decades, as it decommissions the Fukushima Daiichi Nuclear Power Plant, 12 years after it was devastated by a tsunami.
Japan insists the water would be made safe through an Advanced Liquid Processing System (ALPS) and then dilution, but many in the Pacific have raised concerns.
International Atomic Energy Agency (IAEA) director-general Rafael Mariano Grossi has presented the review report to Japanese Prime Minister Fumio Kishida in Tokyo.
The IAEA says the controlled, gradual release as planned by TEPCO would have a "negligible radiological impact on people and the environment".
"Our independent and comprehensive assessment confirms the plans to be in line with IAEA safety standards," Mariano Grossi said.
He said the IAEA will continue to monitor the discharge, which will be released from a tunnel a kilometre off the Japanese coast.
"Assessing a plan is not enough," he said.
"My experts will come back to Fukushima repeatedly, and for as long as the process takes, to take samples at different locations and confirm the water remains safe.
"A clean ocean matters to us all."
The IAEA said the release is a decision for the government of Japan, and its report is not an endorsement of that policy.
While Japan insists the wastewater is to be treated and safe, it will still be radioactive.
An international law expert says Pacific leaders, including Australia and New Zealand, could be undermining the objectives of the South Pacific Nuclear Free Zone Treaty (the Rarotonga Treaty) by not opposing the release.
Ocean currents experts have predicted the wastewater would sweep right across the Pacific.
The Rarotonga Treaty states signatories must "prevent the dumping of radioactive wastes and other radioactive matter by anyone in its territorial sea".
Duncan Currie, who is advising Greenpeace in South Korea on the release, would not go so far as to say Pacific leaders were in breach of the Treaty.
But he said some Pacific leaders were "undermining the objectives of the Rarotonga Treaty by not standing up against Japan's plans".
Prior to the release of the IAEA report, the Pacific Collective on Nuclear Issues called on the Japanese government and TEPCO to abandon their plan effective immediately.
It said the findings of the independent panel of scientific experts commissioned by the Pacific Islands Forum were unequivocal.
"We do not feel assured by the IAEA's confidence in the safety of Japan's proposal, as the agency's remit is promoting the safe use of nuclear energy," the collective said in a statement, released shortly before the IAEA review was presented to Japan.
"The Pacific's long-standing commitment to nuclear abolition includes opposing all forms of nuclear harm to our people, our earth and our ocean, including from uranium mining, nuclear weapons, nuclear testing and nuclear waste."
The collective also called for Pacific leaders to initiate a lawsuit against Japan at the International Tribunal on the Law of the Sea.