Japan has approved an idea to release quite a million tonnes of contaminated water from the destroyed Fukushima nuclear plant into the ocean.
The water is going to be treated and diluted so radiation levels are below those set for a beverage.
But the local fishing industry has strongly opposed the move, as have China and South Korea.
Tokyo says work to release water wont to cool fuel will begin in about two years.
The final approval comes after years of debate and is predicted to require decades to finish.
Reactor buildings at the Fukushima power station were damaged by hydrogen explosions caused by an earthquake and tsunami in 2011. The tsunami knocked out cooling systems to the reactors, three of which melted down.
More than 1,000,000 tonnes of water are wont to cool the melted reactors.
Currently, the radioactive water is treated during a complex filtration process that removes most of the radioactive elements, but some remain, including tritium – deemed harmful to humans only in very large doses.
It is then kept in huge tanks, but the plant’s operator Tokyo electrical power Co (TepCo) is running out of space, with these tanks expected to refill by 2022.
About 1.3 million tonnes of radioactive water – or enough to fill 500 Olympic-sized swimming pools – are currently stored in these tanks, consistent with a Reuters report.
How safe is this water?
Japan argues that the discharge of the wastewater is safe because it is processed to get rid of most radioactive elements and can be greatly diluted.
The plan has the backing of the International nuclear energy Agency, which says the discharge is analogous to the disposal of wastewater at other plants around the world.
“Releasing into the ocean is done elsewhere. It’s not something new. There is no scandal here,” IAEA Director General Rafael Mariano Grossi said in 2021
Scientists argue that the weather remaining within the water is only harmful to humans in large doses. With dilution, the treated water poses no scientifically detectable risk, they say.
While the tritium is radioactive, it’s a half-life of around 12 years, meaning it’ll disappear from the environment over decades instead of centuries.
Radiation from tritium is often ingested, however, which is why fishing industry groups are concerned about the danger of it stepping into the organic phenomenon and being consumed through seafood.
The risk of this happening isn’t zero, but the scientific consensus is that it doesn’t pose a threat to human health.
Scientists also mean that vastly more radiation has been released into the pacific by nuclear weapons tests administered by the US, UK, and France during the 1940s, 50s, and 60s.
What happened in Fukushima?
On 11 March 2011, a 9.0 magnitude earthquake struck off the north-eastern coast of Japan, triggering a 15-meter tsunami.
While the backup systems to stop a meltdown at the Fukushima nuclear plant survived the initial quake, further damage was inflicted by the tsunami.
As the facility’s cooling systems failed within the days that followed, tonnes of material were released. The meltdown was the worst nuclear accident since Chernobyl in 1986.
Around 18,500 people died or disappeared within the quake and tsunami, and quite 160,000 were forced from their homes.