How 500 swimming pools’ worth of water has sparked a panic buy of salt

Twelve years after a tsunami struck Japan’s Fukushima Daiichi nuclear power plant, triggering a humanitarian and environmental catastrophe, the contaminated water used to help prevent further disaster is to be released into the Pacific Ocean.

More than 1 million tonnes of radioactive water, the equivalent to that required to fill 500 Olympic-sized swimming pools, has been stored and treated at the plant since the 2011 disaster after being used to cool damaged reactors.

Review mission members of the International Atomic Energy Authority at Fukushima No.1 nuclear power plant late last year.Credit: Photo: AFP

But the plant cannot store the water forever, and the risk of a leak triggered by a future weather event poses too great a threat, so Japan has just been given the green light to start pumping the water into the Pacific Ocean.

Is it safe? How radioactive is it? And what do Japan’s neighbours have to say?

The nuclear disaster

Disaster reigned on Japan’s north-east coast in March 2011, when a powerful earthquake and resulting tsunami killed about 18,500 people.

The twin natural disasters caused the triple meltdown at the Fukushima plant. To fully decommission the site, more than 1 million cubic meters of treated water must be released.

A satellite image of the damage inland of Minamisoma in Fukushima, taken on March 12, 2011.Credit: DigitalGlobe

Time is running out

It’s a colossal amount of water that has to go somewhere eventually. More than 1000 tanks were built to store it at the plant, but they are due to reach capacity in 2024.

Japanese authorities have given the plant permission to release the water over decades into the Pacific Ocean, but this week two important international rulings are due to secure the go-ahead.

The International Atomic Energy Agency’s Director General, Rafael Grossi, visited Japan to hand down a final report affirming the safety of the process and meeting with officials and Foreign Minister Yoshimasa Hayashi. A further assessment is also expected from a domestic nuclear regulator.

The international regulator found the plan would meet international standards and that its environmental and health impact would be negligible. Grossi said he was very confident about the agency’s “comprehensive, neutral, objective, scientifically sound evaluation” of the plan.

How is the water contaminated?

The 2011 Fukushima triple meltdown was the world’s worst atomic disaster since Chernobyl. Massive volumes of water have accumulated at the power plant ever since, from cooling damaged nuclear reactors and from contaminated groundwater needing to be pumped out.

Before it is stored at the plant, the wastewater is treated by the Tokyo Electric Power Company to remove almost all its radioactive elements (cobalt, strontium and caesium); however one element remains: tritium.

Tanks used to store treated radioactive water used to cool down melted fuel at the Fukushima Daiichi nuclear power plant.Credit: AP

Tritium is a radioactive isotope of hydrogen that is hard to separate from water. It’s considered to be relatively harmless because it does not emit enough energy to penetrate human skin, but some studies have suggested it can raise the risk of cancer if ingested in large quantities.

Professor of Environmental Science at the University of Portsmouth Jim Smith said a person would need to ingest a lot to be given a significant radiation dose.

“As radioactive elements go, tritium is relatively benign and its existence as tritiated water reduces its environmental impact,” he said. “Tritiated water passes through organisms like water does and so does not strongly accumulate in the bodies of living things.”

The World Health Organisation’s drinking water standard for tritium is 10,000 becquerels (a unit of radioactivity) per litre.

A 2023 paper released by the Fisheries Agency of Japan about radiation in seafood since the Fukushima meltdown said water treated at the plant would be released after diluting its tritium concentration with seawater to less than 1500 becquerels per litre – about one-seventh of WHO’s guidelines.

On the global scale, Professor Smith said the proposed Fukushima release will pale in comparison to other sites.

“The La’Hague plant in France emits 450 times more tritium each year into the English Channel than Fukushima plans to release into the Pacific. And there are nuclear power stations in South Korea and China that emit three or four times the amount of tritium each year into the Pacific.”

Not everyone is on board

Despite water containing tritium being routinely released from nuclear plants around the world, and regulatory authorities’ support for dealing with the Fukushima water in this way, not everyone is on board.

Chinese Foreign Ministry spokesman Wang Wenbin left no one in any doubt of Beijing’s view when he said the ocean was “not Japan’s private sewer”.

He warned that releasing the water posed too great a threat to neighbouring countries and Pacific Island nations.

At a regular press conference in Beijing, Wang said it was “neither ethical nor lawful to spill the risk of nuclear contamination to the rest of the world”.

China’s Foreign Ministry spokesman Wang Wenbin.Credit: AP

Responding to the international regulator’s ruling this week, the Chinese Foreign Ministry warned Japan would “bear all the consequences arising from this” if it persisted with the release.

Professor Smith said the remarks from China were nothing more than “propaganda.”

“Unfortunately, humanity, China, Britain, everybody – we dump things in the ocean. Compare radioactive wastewater release to almost any other environmental impact on the earth … the ones we should be focusing on,” he said.

“Climate change, overfishing, plastic pollution, sewage, all going into the Pacific Ocean, all these things are much bigger issues than the Japanese wastewater released … is it the right approach? I haven’t seen a better option.”

Pacific island nations have also raised their concerns. The Pacific Island Forum (PIF), a regional bloc of 17 nations, argues the release of the water, which was used to cool down melted fuel, could have a major impact on fishing grounds that island economies rely on, and where up to half of the world’s tuna is sourced.

What do consumers and fishers think?

In South Korea, demand for sea salt has reportedly rocketed thanks to panicked consumers stockpiling the seasoning amid fears wastewater release could harm future supplies.

Meanwhile, South Korea’s Agriculture Minister Chung Hwang-keun told Reuters the country will not lift a ban on Japanese food products from the area around Fukushima until public concern over contamination has eased.

Customers wait in line to buy 20kg bags of salt in Seoul, South Korea,Credit: Bloomberg

Local reports suggest the fears, along with bad weather and low production, triggered an almost 27 per cent increase in the price of salt from April to June. The market panic prompted the government to distribute 50 metric tonnes each day until mid-July with a 20 per cent discount on the retail price.

In Japan, fishing unions in Fukushima have long pleaded with the government not to release the water, fearful of the harm it will cause to their industry’s already damaged reputation.

However, Professor Smith argued that communities often fear nuclear effects more than scientists think they should.

“After Chernobyl in 2006, the conclusion of the health report from the WHO was that the social and psychological effects of the accident are worse than the direct radiation effects,” he said.

“But Fukushima fishermen know that this will probably damage the value of their produce, even though we, scientists, say this is completely safe.”

As for the salt?

“There’s no basis for this fear. Apart from the incredibly low risks of the water, salt is dry sodium chloride,” Professor Smith said.

When will it happen?

The short answer is, we don’t know. Japan’s government has not set a specific date to begin releasing the water and is still in talks with local communities and the fishing sector.

But when it does begin, it will be a slow process. Estimates suggest passing the water through an undersea tunnel one kilometre offshore into the Pacific Ocean could take as long as 40 years.

Reuters, Bloomberg

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