Here is what we know about the release, how the water has been treated and concerns around the safety of the exercise, according to AFP. Around 100,000 liters of contaminated water – from cooling the crippled plant’s reactors as well as groundwater and rain seeping in – is collected at the site in northeast Japan every day.
Some 1.34 million tons are now stored in around a thousand steel containers at the seaside site, and now there is no more space, authorities say.
Japan decided in 2021, after years of discussion, that it would release at most around 500,000 liters per day into the sea via a pipe one kilometer long.
Plant operator TEPCO says that a special filtering system called ALPS has removed all radioactive elements except tritium.
TEPCO has said it has diluted the water to reduce radioactivity levels.
Tony Hooker, nuclear expert from the University of Adelaide, said that the level of tritium is well below the World Health Organization drinking water limit of 10,000 Bq/L.
“Tritium is regularly released from nuclear power facilities into waterways worldwide,” Hooker told AFP.
“For decades (there have been) no evidential detrimental environmental or health effects,” he said.
UN atomic watchdog the International Atomic Energy Agency (IAEA) has said the release meets international standards and “will not cause any harm to the environment.”
The Japanese government has spent months trying to win over skeptics at home and abroad, with everything from study tours of Fukushima to video live-streams of fish living in the wastewater.
Tokyo has also sought to counter disinformation being peddled online about the release, such as manipulated or old photos and claims – denied by Japan – that it bribed the IAEA.
The far more dangerous task remains removing radioactive debris and highly dangerous nuclear fuel from the three reactors that went into meltdown in 2011.
TEPCO plans to use robots to remove the fuel but there are fears that radiation levels are so high that they could even disable the remote-controlled machines.
The whole gargantuan process is expected to take 30 to 40 years and cost around eight trillion yen ($55 billion).