Fear over sea release plan for Fukushima water

BESIDE the ruins of the Fukushima Daiichi nuclear plant, more than 1 000 huge metal tanks loom in silent testament to one of the worst nuclear disasters in history, the meltdown of three nuclear reactors 10 years ago this month.

The tanks contain nearly 1.25 million tons of cooling-system water from the 2011 disaster and groundwater seepage over the years – most of it still dangerously radioactive.

Running out of space to build more tanks, the government wants to gradually release the water into the sea – after it has been decontaminated and diluted – over the next three decades or more. Even though a formal decision has yet to be announced, the government and the Tokyo Electric Power Co (Tepco) have insisted that an ocean release is their preferred solution and that it is perfectly safe.

The only thing holding them back appears to be the Olympics and the bad publicity it could generate before the Games begin in July, experts say.

The idea of releasing the water has infuriated Fukushima’s fishing community, only now getting back on its feet after ocean contamination following the disaster. Also angry is South Korea, more than 600 miles away on the other side of Japan.

Tepco says the water has already been or will be cleaned with an advanced treatment system, known as ALPS, that is capable of removing almost all radionuclides present in the water, including the really dangerous ones such as strontium and cesium.

What would be left is tritium, a naturally occurring isotope of hydrogen that is considered less dangerous to human health and is routinely released into the ocean by nuclear power plants. Along with tritium would be tiny traces of carbon-14, a radioactive isotope of carbon.

The International Atomic Energy Agency said the release of the water is “technically feasible” and has offered to provide independent radiation monitoring to reassure the public that it would comply with international standards. But when it comes to public trust, the Japanese government and Tepco are on shakier ground.

For years, Tepco claimed that the treated water stored at the plant contained only tritium, but data deep on its website showed that the treatment process had failed to remove many dangerous radionuclides.

Finally, in 2018, it was forced to acknowledge that 70% of the water was still contaminated with dangerous radioactive elements – including strontium-90, a bone-seeking radionuclide that can cause cancer – and will have to be treated again before release.

Tepco explains the contamination by saying it rushed the treatment after the accident because it needed to quickly reduce radiation in the water to manageable levels. Further tests showed ALPS could reduce the concentration of radionuclides to well within international standards, it said..

Shaun Burnie, senior nuclear specialist at Greenpeace Germany, said there were risks involved in releasing tritium and carbon-14 into the sea they and would like to see the release delayed at least until 2035, giving more of the tritium time to decay into hydrogen.

But he ties the decision to the government’s much bigger pledge – to remove all the extremely radioactive corium from the wrecked reactors by 2041 or 2051, even though the technology to do so doesn’t yet exist, along with millions of tons of contaminated topsoil removed from local fields.

In a new report, Greenpeace calls that pledge a “delusion”.

“That’s just not going to happen, but it’s a sort of mantra,” Burnie said. “The water is a symbol. If they can get rid of it, they are meeting that commitment to remove the problem, and that’s why they’ll discharge it into the Pacific.”