Fukushima's Radiation Is Contained By a Mile-Long Wall of Ice (cnet.com)

CNET reports on the massive ice wall created by an "intricate network of small metal pipes, capped off by six-foot-high metal scaffolding." It turns out, coolant is running through the pipes, freezing the soil below and creating an impermeable ice wall that's nearly 100 feet deep and a mile long, encircling the reactors. It's like a smaller-scale subterranean version of the Wall in Game of Thrones, but instead of keeping out White Walkers and wights, this line of defense keeps in a far more realistic danger: radioactive contaminants from melted-down reactors that threaten to spill into the water by Fukushima Daiichi....

The structure, which cost roughly $300 million, paid for by public funds, serves as critical protection, defending the Fukushima area from one of the most radioactive hotspots in the world. While Tokyo Electric Power Co., also known as Tepco, struggles to find a way to remove radioactive material from the facility -- a process the government estimates could take more than four decades -- the more immediate concern is what to do with the contaminated water leaking out from the facility. One of the solutions has been to put up (down?) this underground ice wall, which prevents much of the surrounding groundwater from getting in.

Comments

Re:TLDR; version - no

[mysidia]

The "hottest" isotopes are of the LEAST concern at this point -- the ones that remain are still dangerous. The Ice wall is Not even perfectly watertight. The corium will have radioactivity hazardous to humans and the environment for hundreds of years... the water will contact it and become contaminated, and that contamination will spread into the soil and into the oceans and cause massive long-term damage.

Official Fukushima Report

[MrKaos]

It's been eight years since this disaster occurred.

The official report of The Fukushima Nuclear Accident Independent Investigation Commission contains a wealth of information for anyone interested in the facts regarding this disaster.

The report is scathing and contains lines such as a multitude of errors and willful negligence that left the Fukushima plant unprepared for the events of March 11 and describes the mindset that supported the negligence behind this disaster.

It is very difficult to believe that the company that got the world into this situation is the one that will get us out of it. Chernobyl's New Safe Confinement took the combined resources of the European Union to fund and was designed by the British.

Re:Official Fukushima Report

[AmiMoJo]

One of the most damning lines is this:

"It is thought that the ground motion from the earthquake was strong enough to cause damage to some key safety features"

Also there is evidence that some of the power loss that was a critical factor in the disaster was not due to the tsunami either:

"This suggests that at least the loss of emergency power supply A at Unit 1 might not have been caused by flooding."

In other words there are serious questions about all the other nuclear plants in Japan and anywhere else that might experience seismic shocks. In fact we have to also question terrorism-proofing measures to defend against things like aircraft hitting the reactors, which cause shocks too.

The report also laments the poor response and clean-up by the government, and how the former residents have been treated.

Re:TLDR; version - no

[MrKaos]

incorrect - it will be diluted at that point to the extent it can be detected but does not cause any permanent damage (except idiots who panic about nothing causing alarm to the rest of the population)

Radio-isotopes bio-accumulate in the environment, they do not dilute. They accumulate in the food chain because radio-isotopes appears as micro-nutrients to metabolisms. For example, plutonium chloride is highly soluble and appears like iron to metabolisms, which would be absorbed into blood, for example. Radio-cesium and strontium also have these characteristics.

Re:TLDR; version - no

[thegarbz]

Radio-isotopes bio-accumulate in the environment, they do not dilute.

Either you don't know the meaning of bio-accumulate, the meaning of the word dilute, or the size of the environment.

Just because something can bio-accumulate doesn't mean it isn't also diluted when released into a large environment.

The GP was right, the original assertion that "massive long term damage" is done, used in the same sentence as "soil and ocean" is sensationalist. The only massive long term damage will be in the immediate vicinity of the reactor.

Re:TLDR; version - no

[Cyberax]

No, most radioisotopes do not bioaccumulate: https://www.jstor.org/stable/1... . So the health-related consequences of the Fukushima reactor meltdown are basically nil. Also the ocean is LARGE - there's plenty of water there to dilute the few hundred kilograms of dangerous isotopes that have leaked so far.

Fukushima status

[doom]

The short answer: the "ice wall" is helping to reduce water flow, but isn't perfect, and if you want to spin that in a positive way, you can say "look, it's working!", and if you want to go the other way you can say "it's not working!"-- because anything short of perfection is obviously useless.

A better question would be "how well is it working?" but even better would be "how well does it need to work?".

I'm inclined to agree with our anti-nuclear friends that this is all a bunch of theater to reassure people (much like that that other "wall" we've been hearing so much about). It would be nice if they were just reassured by declining levels of leakage, and little evidence of health impacts, but that kind of message gets lost in the weeds of statistical chatter and "activist" shouting.

Fukushimas Ice Wall Not Working:

A government-commissioned group of experts concluded Wednesday that a costly underground ice wall is only partially effective in reducing the ever-growing amount of contaminated water at Japan's destroyed Fukushima nuclear plant, and said other measures are needed as well.

The panel agreed that the ice wall helps, but said it doesn't completely solve the problem. Panel members suggested that additional measures be taken to minimize the inflow of rainwater and groundwater, such as repairing roofs and other damaged parts of buildings.

Martin Fackler at the NYT commented:

Since the start, the project has attracted its share of skeptics. Some say buried obstacles at the plant, including tunnels that linked the reactor buildings to other structures, will leave holes in the ice wall, making it more like a sieve. Others question why such an exotic solution is necessary when a traditional steel or concrete wall might perform better.

From the World Health Organization faq:

What are the health implications of the Fukushima Daiichi NPS (FDNPS) nuclear accident?

[...] UNSCEAR published a report on the levels and effects of radiation exposure due to the accident. In 2015, UNSCEAR released a white paper that evaluates new information in the peer-reviewed literature.

There were no acute radiation injuries or deaths among the workers or the public due to exposure to radiation resulting from the FDNPS accident.

Considering the level of estimated doses, the lifetime radiation-induced cancer risks other than thyroid are small and much smaller than the lifetime baseline cancer risks. [...] There have been recent reports about thyroid cancer cases being diagnosed among children exposed to low doses of radioactive iodine as a result of the Fukushima accident. These reports should be interpreted with caution. [...] The substantial number of cases that have already been observed in the Fukushima Health Management Survey have been considered likely due to the sensitivity of the screening rather than to radiation exposure.

From a global health perspective, the health risks directly related to radiation exposure are low in Japan and extremely low in neighbouring countries and the rest of the world.

"Bio-concentration" is essentially not happening: Insignificant Environmental and Public Health Risk from Fukushima in North America 8 Years On