12 years after nuclear meltdown
Disposal of Fukushima cooling water into the sea is getting closer
The diluted cooling water is currently stored in huge tanks on the site of the Fukushima nuclear ruins. photo
© Shohei Miyano/Kyodo News/AP/dpa
More than 10 years ago there was a super meltdown in Fukushima. The system still has to be cooled. But what to do with the cooling water? Japan wants to start disposing of it soon, but the plan has met with criticism.
The start of Japan’s controversial disposal of vast amounts of diluted cooling water from the Fukushima nuclear ruins is drawing near. According to Japanese media, representatives of the nuclear regulatory authority want to inspect the systems for discharging the treated water into the sea at the weekend. There is criticism of the project, and researchers are also discussing it controversially.
After completing a test run, the agency must conduct a preliminary review before it can begin discharging the water into an approximately one-kilometer-long submarine tunnel that empties into the ocean. This is expected this summer. Disposal could take decades. According to Japanese media, the Director-General of the International Atomic Energy Agency (IAEA), Rafael Grossi, plans to come to Japan early next month for a meeting with Prime Minister Fumio Kishida.
On March 11, 2011, a severe earthquake and huge tsunami caused a super meltdown at the Fukushima Daiichi nuclear power plant. More than twelve years later, the reactors destroyed in the process still have to be cooled with water. Due to infiltrating rainwater and groundwater, the amount of irradiated water is increasing every day. So far, it has been stored in hundreds of huge tanks, but now the space is running out, according to operator Tepco. According to the Japanese television station NHK, the amount now amounts to more than 1.3 million tons. That corresponds to about 97 percent of the tank capacity.
Isotope tritium cannot be filtered out
The government therefore decided in 2021 that the water would be channeled into the Pacific. The contaminated cooling water is filtered, but the ALPS filter system cannot filter out the tritium isotope. According to operator Tepco and the Atomic Energy Agency IAEA, however, this should not pose a risk.
Japan argues that tritium is harmless to humans in small amounts. According to the NHK, the water is diluted to such an extent that the tritium concentration drops to around 1,500 becquerels per liter, which corresponds to one fortieth of the national threshold. However, environmentalists, neighboring countries and local fishing communities oppose the project. The fishermen fear further damage to the reputation of their products.
“Reasonable and safe”
“It sounds like a terrible idea, but it’s actually sensible and safe,” argues Nigel Marks, a professor of physics and astronomy at Curtin University in Australia. Nuclear power plants around the world have routinely discharged contaminated cooling water into the sea for decades. “And nothing bad ever happened,” says the scientist. The Pacific Ocean contains 8400 grams of pure tritium. Japan only wants to release 0.06 grams of tritium every year. “The tiny amount of extra radiation doesn’t make the slightest difference.”
In contrast, Robert Richmond, director of the Kewalo Marine Laboratory at the University of Hawaii, called Japan’s plan “premature and inadvisable at this time”. The radiological environmental impact assessment prepared by the operating company Tepco was “defective and insufficient”. The same applies to the monitoring plans, “which are not aimed at protecting the ecosystem, but only at detection,” according to the expert. The potential negative impacts would come on top of other stressors already affecting the health of the oceans and the people who depend on them.