The TLDR: The Japanese government plans to release 1.25 million tonnes of treated radioactive water into the sea. This is water from its Fukushima nuclear reactor which was damaged during the catastrophic 2011 earthquake. The announcement has triggered a diplomatic furore plus angry protests by nuclear activists and the fishing industry. The fracas raises bigger questions about the safety of nuclear power—or at least, our ability to trust it as a safe alternative to conventional sources of energy.

Fukushima meltdown: a quick recap

The earthquake: Back in 2011, a 9.0 earthquake shook Japan—and the entire planet, shifting Earth off its axis by almost 10 metres. It was followed by a massive 14-metre tsunami wave that swept across Fukushima Prefecture—the location of the Fukushima Daiichi Nuclear Power Plant, located in the coastal town of Okuma. Here’s a map that helps you see the lay of the land: 

The nuclear plant: is owned by a Japanese company TEPCO. When the earthquake was first detected, the emergency systems shut down the reactors—and turned on the backup generator to keep pumping coolant to cool the incredibly hot cores. But the following tsunami knocked out the generators. Soon three of the reactors overheated and partly melted the cores—which is called a triple nuclear meltdown. 

Point to note: there were 2,313 deaths due to the earthquake, but only one person died due to radiation. That said, the Fukushima meltdown is classified as a level seven event—which is the highest category, and second only to the 1986 Chernobyl disaster.

This radioactive water is from the tsunami?

Not exactly. Part of it is water used to cool the reactors after the disaster. Then there is all the rain and groundwater that has seeped into the facility:

“Ever since [the tsunami] TEPCO must inject water into the reactors indefinitely to keep the melted cores cool, but water tainted by contact with the fuel and associated debris has been leaking from the damaged containment vessels and into the basements of the reactor buildings, where tonnes of fresh groundwater flows in daily through holes in their damaged walls.”

TEPCO has reduced the water accumulation from 300 tonnes to 83 tonnes a day—but it still adds up to 1.25 million tonnes sitting in nearly a thousand storage tanks. That’s the equivalent of 500 Olympic-size swimming pools.

So why not just keep it stored and safe?

Because TEPCO is running out of space. Each storage tank is around 10 metres tall and holds 1,000 to 1,200 tonnes. A tank fills up within 7-10 days. And there’s simply not enough room to keep building more of these tanks. The nuclear site is going to be full by next year. And TEPCO wants to decommission the reactor between 2041-2051—which will first require getting rid of these tanks—that have to be torn down so the space can be used to store spent fuel and melted fuel debris extracted from the damaged reactors.

As of May 2020, TEPCO had spent $3.3 billion just on fuel debris removal at Fukushima.

So they’re going to just dump it?

No. First, all that water will be treated to make it ‘safe’—the definition of which is now the source of the big fight. They are using a process called ALPS (Advanced Liquid Processing System)—which extracts tonnes of newly contaminated water every day, filtering out most of the radioactive elements. 

But, but, but: The process cannot entirely eliminate a substance called Tritium—a radioactive isotope of hydrogen, which is harmful to humans if it is present in high doses. So the Japanese government is taking an additional step: 

“It has pledged to dilute the water to be released into the Pacific Ocean to 2.5% of the tritium limits required under international standards for sea discharge. This level is equivalent to one-seventh of World Health Organisation guidelines for tritium levels in safe drinking water. Drinking up to two litres of tritiated water a day is said to still be well below the amount of radiation exposure that would affect one’s health.”

The big plan: is to gradually start releasing this diluted water into the Pacific Ocean in two years, and continue to do so for the next 30 years at a cost of nearly $76 billion. 

So why is everyone upset? 

The plan has been opposed by three different constituencies: Neighbouring countries, environmental and anti-nuclear groups, and the fishing industry in Fukushima.

Neighbouring countries: 

• China claims that the Japanese government has been “extremely irresponsible” by not properly consulting its neighbours before taking this decision. It has also called for an independent international scientific assessment. 
• South Korea expressed “strong regret and serious concerns”—and plans to move an international tribunal to block the move.
• Russia claims that Japan’s explanations about its plans are “insufficient” and cause of “serious concern”—and is asking for “detailed explanations on all aspects.”

Anti-nuclear and enviro groups: Some 30 groups have called the move “nuclear terrorism”—claiming that Tokyo is deliberately focusing on Tritium to deflect attention from other more dangerous substances: 

• Greenpeace claims that the water contains as much as 63.6GBq (gigabecquerels) of carbon-14—a radioactive form of carbon that is a "major contributor to collective human radiation dose and has the potential to damage human DNA."
• Another Greenpeace activist claims that leaked TEPCO documents show that it has not been able to eliminate numerous radioactive elements, including iodine, ruthenium, rhodium, antimony, tellurium, cobalt and strontium-90.
• And even those not alleging bad faith warn that international bodies have to ensure “stringent monitoring” of these other hazardous substances.

Fishing community: The fishing industry is worried about consumer boycotts and import bans. More than 20 countries still have strict restrictions over food imports from Japan—which were first imposed after the 2011 earthquake. And the release of this water will trigger even tougher regulations. The local fishermen say fears of contaminated water will “kill the industry and take away the life of the boats… The fish won’t sell”—even if the water is safe. 

So is the water safe or not?

Tritium: Most scientists agree that its presence is not a major concern: “The health impact will be almost zero. We are surrounded by radiation in our daily life, and this release will not affect humans, marine life or the ocean itself.”

Carbon 14: Here, the experts say it depends on the quantity: 

"People have discharged carbon-14 into the sea over many years. It all comes down to how much is there, how much is dispersed, does it enter marine food chains and find its way back to people?"

According to TEPCO, the concentration is very low—and way below the recommended safety levels. 

Strontium 90: This is a legitimate concern. TEPCO has confirmed that levels of strontium 90 are more than 100 times above legally permitted levels in nearly 65,000 tonnes of water that had already been treated. And in some storage tanks, they were 20,000 times above safety levels set by the government.

Point to note: As of now, only about a fifth of the stored water had been effectively treated. And more than three-quarters of it still contains radioactive material other than tritium—and at higher levels than the government considers safe for human health.

And a reminder for Indians: Forget nuclear reactors. In India, uranium mining to power our reactors is already turning our rivers toxic, and hazardous to the health of Indians—as this report makes painfully clear. Also see: Kudankulam.

The bottomline: Nuclear plants routinely treat and discharge their water into the sea. What makes Fukushima notable is the sheer volume involved. And given the existing technology, there isn’t another viable or safer way to get rid of this 1.25 million tonnes at this time. And storing such vast amounts of radioactive water on land is hardly safe.

But the experience of Fukushima raises a big and tricky question for all of us: How ‘safe’ and ‘sustainable’ is nuclear power? In a country addicted to coal, there are no easy answers.

Reading list

• Washington Post, Guardian and Al Jazeera have the most detailed explainers on Japan’s Fukushima plan. 
• Also in Al Jazeera: A reporter’s account of the devastation wreaked by the earthquake, and a collection of images and infographics. 
• New York Times reports on the fears of the fishing community and neighbouring Asian countries.
• Forbes makes a strong case for Japan’s plan, emphasizing why it is practical and safe.
• Engineering and Technology has a piece on the future of radioactive waste disposal.
• This report by The Centre of Public Integrity looks at how the Indian nuclear industry dumps its waste into our rivers.