At Fukushima plant, a million-tonne headache: radioactive water

Staff measure radiation levels around the storage tanks of radiation-contaminated water at the tsunami-crippled Tokyo Electric P
Staff measure radiation levels around the storage tanks of radiation-contaminated water at the tsunami-crippled Tokyo Electric Power Company (TEPCO) Fukushima Dai-ichi nuclear power plant in Japan

In the grounds of the ravaged Fukushima Daiichi nuclear plant sits a million-tonne headache for the plant's operators and Japan's government: tank after tank of water contaminated with radioactive elements.

What to do with the enormous amount of , which grows by around 150 tonnes a day, is a thorny question, with controversy surrounding a long-standing proposal to discharge it into the sea, after extensive decontamination.

The water comes from several different sources: some is used for cooling at the plant, which suffered a meltdown after it was hit by a tsunami triggered by a in March 2011.

Groundwater that seeps into the plant daily, along with rainwater, add to the problem.

A thousand, towering tanks have now replaced many of the cherry trees that once dotted the plant's ground.

Each can hold 1,200 tonnes, and most of them are already full.

"We will build more on the site until the end of 2020, and we think all the tanks will be full by around the summer of 2022," said Junichi Matsumoto, an official with the unit of plant operator TEPCO in charge of dismantling the site.

TEPCO has been struggling with the problem for years, taking various measures to limit the amount of groundwater entering the site.

There is also an extensive pumping and filtration system, that each day brings up tonnes of newly contaminated water and filters out as many of the as possible.

Tritium remains in filtered contaminated water at Fukushima Dai-ichi nuclear plant in Okuma, Japan
Tritium remains in filtered contaminated water at Fukushima Dai-ichi nuclear plant in Okuma, Japan

Highly radioactive

The hangar where the decontamination system runs is designated "Zone Y"—a requiring special protections.

All those entering must wear elaborate protection: a full body suit, three layers of socks, three layers of gloves, a double cap topped by a helmet, a vest with a pocket carrying a dosimeter, a full-face respirator mask and special shoes.

Most of the outfit has to burned after use.

"The machinery filters contain radionuclides, so you have to be very protected here, just like with the buildings where the reactors are," explained TEPCO risk communicator Katsutoshi Oyama.

TEPCO has been filtering newly contaminated water for years, but much of it needs to go through the process again because early versions of the filtration process did not fully remove some dangerous radioactive elements, including strontium 90.

The current process is more effective, removing or reducing around 60 radionuclides to levels accepted by the International Atomic Energy Agency (IAEA) for water being discharged.

But there is one that remains, which cannot be removed with the current technology: tritium.

Tritium is naturally present in the environment, and has also been discharged in its artificial form into the environment by the nuclear industry around the world.

There is little evidence that it causes harm to humans except in very high concentrations and the IAEA argues that properly filtered Fukushima water could be diluted with seawater and then safely released into the ocean without causing environmental problems.

Tanks of water contaminated with radioactive elements are a million-tonne headache for the operators of the ravaged Fukushima Da
Tanks of water contaminated with radioactive elements are a million-tonne headache for the operators of the ravaged Fukushima Daiichi nuclear plant and for Japan's government

'Absolutely against it'

But those assurances are of little comfort to many in the region, particularly Fukushima's fishing industry which, like local farmers, has suffered from the outside perception that food from the region is unsafe.

Kyoichi Kamiyama, director of the radioactivity research department at the regional government's Fisheries and Marine Science Research Centre, points out that local fishermen are still struggling eight years after the disaster.

"Discharging into the ocean? I'm absolutely against it," he told AFP.

At the national government level, the view is more sanguine.

"We want to study how to minimise the damage (from a potential discharge) to the region's reputation and Fukushima products," an Industry Ministry official said.

The government is sensitive to fears that people inside Japan and further afield will view any discharge as sending radioactive waste into the sea.

No decisions are likely in the near-term, with the country sensitive to the international spotlight that will fall on Japan as it hosts the Olympic Games next year.

Environmentalists are also resolutely opposed to any discharge into the sea, and Greenpeace argues that TEPCO cannot trusted to properly decontaminate the water.

The solution, said Greenpeace senior nuclear specialist Shaun Burnie, "ultimately can only be long-term storage and processing."


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Japan still weighing dump of Fukushima radioactive water into ocean

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Oct 05, 2019
But those assurances are of little comfort to many in the region,

This tells me those people are being stupidly emotional and irrational for not accepting the scientific facts that say what IAEA is proposing is perfectly safe. If I was one of those people in the region, even if I had been personally very badly effected by the disaster with loved one's lost etc, I would still NOT ever reject the scientific facts, because I think that is just being STUPID.

Oct 05, 2019
because I think that is just being STUPID


The alternative is being easily led. Consider that the opposition is spreading false information about the matter and actively trying to convince the fishers and the local population that the IAEA is wrong and tritium is the end of the world (the "holocaust theory" of nuclear safety: there is no safe level).

This is because the people who oppose nuclear power genuinely believe they're doing the people and the world a favor by lying and obstructing the attempts to clean up nuclear waste; that the cause of removing nuclear power is more important than actually dealing with the immediate problems, and in fact the problems simply make the argument stronger.

It's like complaining that your car is deadly unsafe because the brakes are faulty, then refusing to fix the car because then you couldn't complain. The point is to get rid of nuclear power for other reasons that you can't reveal, because they are not rational or reasonable.

Oct 05, 2019
Given Tritium's half-life of 12.3-ish years, unless they can devise an industrial-scale process to purge & concentrate the stuff, they've a century's wait on their hands...

Oct 05, 2019
they've a century's wait on their hands...


Why?

After three half-lives, close to 90% of the stuff is just gone.

Secondly, tritium as a radio-isotope is weak. It emits electrons with an average energy of 5.7 keV which means the ionizing radiation you're exposed to is actually weaker than the amount of static electricity you get when you shuffle your feet across a carpet. Worse sources of ionization are present in your everyday environment in abundance.

Thirdly, its biological half-life in the body is 10 days. Tritiated water behaves differently than regular water in chemical reactions, and it gets rejected by the body because it doesn't work right. It doesn't bio-accumulate.

Oct 05, 2019
In fact, tritium is such a weak radioactive element that it's actually difficult to even measure its presence in a body of water.

That's because the radiation is absorbed within 6 millimeters of plain air. Mixed in water, the radiation simply does not escape the water. You could put a geiger counter tube in the contaminated water and it most likely wouldn't detect anything out of the ordinary. If anything, it would show less radiation because the water shields it from the ambient radiation.

The way tritium is detected in water is by mixing in a scintillation chemical, like zinc sulfide, which produces tiny flashes of light when a tritium atom breaks down right next to the sulfide molecule and makes it fluorescence - which makes it kinda like your glow-in-dark watch dials that have a small vial of tritium in them.


Oct 05, 2019
Dilution is the solution to pollution.

Oct 05, 2019
Sorry, Eikka, you're using logic.
You are correct, I even remember enough of my Uni 'side' of 'Nuclear & Radio-Chemistry' to nod briskly but, IMHO, the Fukushima taint will so stick.
No, three half-lives will not suffice to allay fears...
Doesn't help that the industry has 'blown its cred'. Built sea-wall lower than historical tsunami flood-marker at near-by port ? Built essential systems such any flood would swamp them ?? Yeah, right...

Oct 06, 2019
No, three half-lives will not suffice to allay fears...


At some point you just have to ignore the hysteric people and do it - otherwise the issue isn't going to be solved 100 years from now either, because there's still some tritium in the water...

If you listen to the fearmongers, they will tell you that nuclear waste remains dangerous forever. It's like homeopathy - once touched by evil nuclear power, the water is contaminated forever and ever. Again, the point isn't to solve the problem, but to erect a totem pole out of the problem as an anti-establishment political symbol - to remind your followers about how evil the other guys are for not fixing a problem you are refusing them to fix.

Oct 07, 2019
The alternative is being easily led.

But by whom? At some point non-experts like me will have to take someone's word.

I tend to side with the scientists, but I don't fault those who don't trust the owners of a nuclear plant that already had a major disaster.

Oct 07, 2019
The alternative is being easily led.

But by whom? At some point non-experts like me will have to take someone's word.


Well, you could pick someone who doesn't do politics with environmental causes, like, not Greenpeace and pals whose real agendas are elsewhere, who have been caught lying and exaggerating before. They're basically trolling for money and political influence at the pretense of environmentalism. It's not entirely difficult to read up a little bit on the matter and decide for yourself who's probably telling the truth and who's just trying to incite hysteria.

I don't fault those who don't trust the owners of a nuclear plant that already had a major disaster.


The IAEA doesn't own Fukushima. The problem here is that people tend to choose conspiracy theories over experts because they want to be martyrs - they want to believe, because being accepted as victims gives them the publicity and the power to demand things out of the society.

Oct 07, 2019
For example, if fishermen are seeing their sales go down because people are wary of eating fish caught near Fukushima, what is the easier course of action for the fishermen to restore their income?

A) try to convince the world that the fish is safe to eat, against all those who make politics out of saying it's not
B) agree the fish is NOT safe to eat, and therefore you deserve damages and restitution from the society

It's easier to go along with the public sentiment and accept the role of a victim if it means you get compensated for it. At least you're getting something.

And, some fishermen who weren't making much money in the first place actually stand to gain by claiming compensation - these unscrupulous fishermen start going around claiming the fish is not safe in order to earn money, which brings down the rest of them.

Oct 07, 2019
That's the fundamental problem of a society that makes its purpose in dispensing social justice: when you go around fixing other peoples problems and playing Robin Hood with their money, people start making up problems in order to goad you into "helping" them in particular. All they need is a plausible excuse, and you can't tell real issues from someone just rubbing up the thermometer to skip school.

Like a person who throws themselves in front of a moving car in order to sue the driver.

Oct 07, 2019
https://www.thegu...industry

On this occasion, as on every other day since fishing in Soma resumed at the end of June, the two radiation-measuring devices in the lab revealed not even the slightest trace of radioactive iodine-131, and caesium-134 and -137. In March, the government introduced stricter acceptable radiation levels in seafood, increased from 500 becquerels per kilo to 100 becquerels.

"There may be very tiny amounts, but they are so small they don't even register on equipment as sophisticated as this," says Noriaki Haga, the fisheries official in charge of testing.


That was a year after the disaster. Since then, TEPCO has released runoff water on several occasions, and the fishermen gave their OK. Yet, despite the fact that no measurable levels of contaminants are found in the seafood, they have to go through this media circus again and again.

Oct 07, 2019
Everyone consumes tritium every day and in human history there has never been a time where we did not consume tritium every day. The oceans are full of billions and billions of times more tritium than are contained in the tanks at Fukushima.

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