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Fukushima nuclear plant's wastewater will be released into the ocean, Japan says

The treated wastewater from the ruined facility will slowly be dumped into the Pacific over the next decade.

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3 min read
People with signs protesting Japan's plan to release contaminated water from Fukushima into the ocean

Demonstrators protest outside of the Japanese prime minister's official residence on April 12, ahead of the decision on how to dispose of contaminated water from the Fukushima nuclear power plant.

Takashi Aoyama/Getty

The Japanese government has announced plans to dump more than 1 million tons of treated wastewater from the ruined Fukushima Daiichi nuclear power plant into the Pacific Ocean over several decades. The potential release was flagged last year, when former environment minister Yoshiaki Harada said that draining the water into the sea was "the only option." 

The wastewater has been steadily accumulating in storage tanks at the site for a decade, after a tsunami flooded the plant in 2011. The Tokyo Electric Power Company, which manages the site, believes storage will run out in 2022. The release of contaminated water is expected to begin a year later, in 2023.

"We're conscious of the fact that we can't keep storing more and more water," Kenji Abe, a spokesman for Tepco's decommissioning and decontamination unit, told CNET's Roger Cheng in 2018

After a devastating double earthquake off the northeastern coast of Japan in 2011, Fukushima's reactors shut down. But the quake resulted in a tsunami, almost 50 feet high, that engulfed and flooded the plant. Three of the four reactors at the plant overheated, causing meltdowns and explosions. It was the worst nuclear disaster since Chernobyl in 1986, forcing over 150,000 to evacuate homes within a 12.5 mile radius of the plant. 

Although wildlife thrives in the evacuation zone, the destroyed reactors are still radioactive. Any water that is pumped in as coolant, or collected from the ground or rain, becomes contaminated. This water is treated by a process known as ALPS (advanced liquid processing system) that is able to remove some of the radioactive contamination -- but not all of it. 

Treatment technologies allow 62 of the 63 radioactive elements in the water to be cleansed, but one remains: tritium.

This rare form of hydrogen remains in the treated water that will now be flushed out to sea. It's not believed to cause significant human health risks in small doses. However, the water may need to undergo additional treatment before release, according to The New York Times, which reported in 2019 that more than 75% of the water still contained material other than tritium.

"The optics are terrible, but the Japanese government is actually doing the right thing," said Nigel Marks, a researcher at Curtin University in Australia who has held grants on radioactive waste technology with Australia's Nuclear Science and Technology Organisation.

"By diluting the tritium/water mixture with regular sea water, the level of radioactivity can be reduced to safe levels comparable to those associated with radiation from granite rocks, bore water, medical imaging, airline travel and certain types of food."

The decision, announced by Prime Minister Yoshihide Suga, will not come as welcome news for Fukushima's fishermen. Last year, the head of Japan's fisheries unions said releasing the water would have a "catastrophic impact" on the industry, according to Reuters. The public's faith in the safety of fish has been shaken.

International environmental organization Greenpeace strongly condemned the decision, stating that it "ignores human rights and international maritime law" and that the government has "opted for the cheapest option" in dealing with the radioactive waste.