What contains water from Fukushima dumped into the sea – 08/26/2023 – Science

The fear of Japanese citizens and the criticism received from China were not enough to prevent Japan from starting releasing treated wastewater from the Fukushima nuclear power plant into the Pacific Ocean on Thursday (24).

More than a million tons of wastewater have accumulated since the 2011 tsunami, which severely damaged the plant’s facilities.

According to the Japanese government, the risk of contamination is minimal, due to the processes used to filter the water. And the plan received the support of the United Nations nuclear control body, the IAEA (International Atomic Energy Agency).

But the initiative generates controversy in the region. Local communities fear that possible environmental damage will harm fishing and other economic activities.

The plan also faces strong opposition from China, which is the main buyer of Japanese seafood. Beijing accuses Japan of treating the ocean as its “private sewer” and considers the IAEA to be a “unilateral” body.

On Thursday (24/8), as soon as Japan started launching the waters, the Chinese government announced that it will ban all seafood imports from the region, to “protect the health of Chinese consumers”, according to the customs of the country.

It is estimated that this measure will cause serious economic damage and Japan itself has acknowledged that its companies will suffer a “significant” blow.

Together, Hong Kong and China each year import more than US$ 1.1 million (about R$ 5.4 million) in products originating from the sea of ​​Japan. This amount represents almost half of Japanese exports of seafood .

South Korea also has a long-standing ban on some marine products from Japan, but had no further comment last Thursday.

South Korean Prime Minister Han Duck-soo said “the important thing now is whether Japan will strictly follow scientific standards and provide information transparently, as it has promised the international community.”

Seoul and Tokyo have been strengthening diplomatic relations, despite their deep historical disagreements. They have united in alliance with the United States in the face of threats from North Korea and China.

But most South Koreans oppose the release of water from Fukushima and protesters tried to storm the Japanese Embassy in Seoul on Thursday. Other manifestations of indignation were also recorded in Hong Kong and Tokyo.

What happens at the Fukushima power plant?

Since the 2011 disaster, Tepco – the company that owns the Fukushima plant – has been pumping water to cool the damaged nuclear reactors.

As a result, the plant produces daily contaminated water – around 100 m³ per day – which is stored in gigantic tanks.

So far, there are more than 1,000 tanks filled with water. Japan claims that this solution is not sustainable in the long term, and so it has started to gradually release this water into the Pacific Ocean. This process is estimated to take 30 years.

Discharging wastewater into the ocean is routine practice at nuclear power plants. But this situation is the result of an accident and not a typical nuclear waste.

Tepco filters Fukushima’s waters through its Advanced Liquid Processing System, which reduces most radioactive substances to acceptable safety standards, with the exception of tritium and carbon-14.

Tritium and carbon-14 are radioactive forms of hydrogen and carbon, respectively. It is difficult to separate them from the water.

These substances are present in the natural environment, in water and even in humans, as they are formed in the Earth’s atmosphere and can enter the water cycle. Both emit low levels of radiation, but can pose risks if consumed in large quantities.

Before being released into the ocean, filtered wastewater is diluted with seawater to reduce the concentration of substances still present.

Tepco claims its valve system prevents the accidental release of undiluted wastewater.

And the Japanese government adds that the final levels of tritium —about 1,500 becquerels per liter— are much safer than the levels required by regulatory bodies for the disposal of nuclear waste, or by the WHO (World Health Organization) for water. drinkable.

Tepco also claims that carbon-14 levels are within international safety standards. The company and the Japanese government have conducted studies to demonstrate that the discharged water poses little risk to humans and marine life.

Many scientists also supported the plan.

“The discarded water will be a drop in the ocean, both in volume and in radioactivity. There is no evidence that these extremely low levels of radioisotopes have a harmful effect on health,” said molecular pathologist Gerry Thomas, who worked with Japanese scientists on research on radiation and advised the IAEA on reports produced by the agency on Fukushima.

What do the critics say?

But not everyone is convinced by the arguments of the company and the Japanese government.

Prior to the announcement of the plan’s approval by the IAEA, the NGO Greenpeace published reports raising concerns about the treatment process conducted by Tepco. She claims that it is not enough to remove the radioactive substances.

For the critics of the plan, Japan should, for the time being, keep the treated water in the tanks, which would buy time to develop new processing technologies and for the remaining radioactivity to be reduced naturally.

Some scientists are also concerned about the Japanese plan. They argue that more studies are needed on the possible effects of these residues on the ocean floor and marine life.

“We’ve seen inadequate assessment of the radiological and ecological impact. We’re concerned not only that Japan may not be able to detect what it’s putting in the water [do mar]in sediments and organisms, but also, if that happens, of being unable to remove [o material contaminado]. There’s no way to put the genie back in the bottle,” marine biologist Robert Richmond, a professor at the University of Hawaii, explained to the BBC.

Tatsujiro Suzuki, professor of nuclear engineering at the Research Center for the Elimination of Nuclear Weapons at Nagasaki University in Japan, told the BBC that the plan “would not necessarily lead to serious contamination or public harm, if all goes well”.

But, as Tepco failed in 2011 and failed to avert the disaster, he fears that a possible accident could release contaminated water without treatment.

What’s behind China’s reaction?

Several analysts argue that China’s reaction is not only motivated by environmental concerns, but also by political issues.

Relations between Tokyo and Beijing have deteriorated in recent years. Japan has been reaching out to the United States and demonstrating its support for the autonomous island of Taiwan, claimed by China.

“This incident is more a symptom than a cause of deteriorating Sino-Japanese relations,” says Chinese foreign policy expert Neil Thomas of the Asia Society Policy Institute think tank.

For him, “Beijing would perhaps have made less of a scandal over the release of the water if its relations with Tokyo had been in a better position”.

Japan is likely “to repudiate this criticism, but unlikely to do anything provocative,” according to Professor James DJ Brown, an expert on Japanese foreign policy on the campus of Temple University in Japan.

“Although the government of Japan is deeply concerned about the actions it considers aggressive by the Chinese Communist Party, it understands that it is convenient to maintain stable relations with its biggest neighbor”, explains the professor.

And maybe you don’t have to wait too long. After all, there are those who believe in the possibility that China will not comply with the ban on importing seafood from Japan.

“China’s escalating economic difficulties could make any ban relatively brief and limited to reduce the negative impact on Chinese importers and business sentiment,” adds Thomas.

How is Japan responding to the criticism?

The Government of Japan and Tepco have launched extensive public education campaigns. Japanese Prime Minister Fumio Kishida promised “a high level of transparency” in the process.

Tepco has committed to publishing real-time data on the levels of radioactivity in the water, on a dedicated portal explaining the Fukushima water treatment and disposal process in several languages.

Foreign delegations and media – including the BBC – were invited to take guided tours of the processing facilities. And on the diplomatic front, Tokyo has started talks with its neighbors.

Texts published on the website of the Ministry of Foreign Affairs of Japan point out that other nuclear power plants in the region, especially in China, release water with much higher levels of tritium.

The BBC was able to confirm some of the figures provided by the Japanese government with publicly available information from Chinese nuclear power plants.

But the biggest argument could be the IAEA report, published by the head of the agency, Rafael Grossi, during his visit to Japan in July. The report was released after a two-year investigation.

The agency concluded that Tepco and the Japanese authorities are complying with international safety standards in several aspects, which include facilities, inspections and compliance, environmental monitoring and radioactivity assessments.

Grossi said the plan would have “negligible radiological impact on people and the environment”.

*In collaboration with Tessa Wong, Yuna Kim and Chika Nakayama.

The text was originally published here.