Fukushima: Japan’s new PM won’t delay release of contaminated water into ocean

Japan’s new prime minister, Fumio Kishida, has said that there can be no delay to plans to release contaminated water from the wrecked Fukushima Daiichi nuclear power plant into the sea, despite opposition from fishers and neighbouring countries.

Kishida, who made his first trip to the plant at the weekend since becoming prime minister last month, said every effort would be made to reassure local people that disposing of the water in the Pacific Ocean was safe.

The wastewater, which is pumped up from reactor basements and treated to remove all but one radioactive material, has built up at the site since the plant suffered a triple meltdown in March 2011.

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“I felt strongly that the water issue is a crucial one that should not be pushed back,” Kishida told reporters after being shown around by the plant’s operator, Tokyo Electric Power.

More than one million tonnes of water are being stored in 1,000 tanks at the site, and Tepco has warned that space will run out late next year.

The government and Tepco said in April that work to release the heavily diluted water would begin in the spring of 2023 and take decades to complete.

The move is opposed by nearby fishing communities which say it will undo years of hard work rebuilding their industry’s reputation since the plant was struck by a huge tsunami in March 2011, soon after Japan’s north-east coast was rocked by a magnitude-9 earthquake.

The decision ended years of debate over what to do with the water, with other options including evaporation or the construction of more storage tanks at other sites.

Neighbouring South Korea, which still bans seafood imports from the region, has repeatedly voiced concern, claiming that discharging the water represented a “grave threat” to the marine environment.

The South Korean Olympic committee made separate catering arrangements for the country’s athletes during the Tokyo Olympics amid concern they could be served food from Fukushima, even though produce from the region undergoes rigorous safety checks.

Japan’s government says releasing the water is the most realistic option and will enable workers at the site to proceed with decommissioning the plant – a costly operation that is expected to take about 40 years.

Related: Fukushima: Japan announces it will dump contaminated water into sea

“We will provide explanations about safety from a scientific viewpoint and transparency in order to address people’s concerns,” Kishida said.

Japan has requested help from the International Atomic Energy Agency to ensure the discharge meets global safety standards, including treating the wastewater so its radioactivity levels are below legal limits.

Tepco’s Advanced Liquid Processing System reduces radioactive substances in the water to safe levels, but the system is unable to filter out tritium, a radioactive isotope of hydrogen.

Experts say tritium, a radioactive isotope of hydrogen, is only harmful to humans in very large doses, while government and Tepco officials have pointed out that working nuclear plants routinely dilute and release tritium into the ocean.

Kishida, who supports the restart of nuclear reactors that were idled after the Fukushima meltdown, offered flowers and prayed at a monument to the disaster in Namie, one of several communities near the plant that were declared no-go zones after the disaster. Some residents have since returned to their homes after evacuation orders were lifted.

Kishida has said that nuclear power must be part of Japan’s energy mix if it is to become carbon neutral by 2050. But he has yet to confirm if he will attend the Cop26 climate summit in Glasgow early next month, with Japanese media reports suggesting he won’t decide until after lower house elections are held at the end of this month.

Boris Johnson encouraged Kishida to attend the summit during a phone call last week, adding that Britain was considering lifting import restrictions on Fukushima produce that were introduced while it was a member of the European Union, according to the Kyodo news agency.