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TEPCO having trouble with 'ice wall' at Fukushima plant

44 Comments

Tokyo Electric Power Co (TEPCO), which operates the stricken Fukushima Daiichi nuclear power plant, is still having trouble with an ice wall that was designed to stem the flow of radioactive water seeping from the crippled reactors.

TEPCO said this week that it has extended the termination date for the project, TV Asahi reported Tuesday.

The original plan was to collect large amounts of radioactive particulate contaminated water and funnel it into trenches, freeze it, and then transport it to safe disposal sites elsewhere. However, TEPCO said workers have been adding more and more ice and ice water to the tunnel, but have yet to achieve a complete freeze to allow for safe transportation.

Although workers will begin once again pouring chemicals and other materials into the trenches in hopes of lowering the temperature enough to achieve a full freeze, experts are not expecting any results for at least another two or more months.

Apparently a small stream of water has kept the ice wall from freezing properly. TEPCO said it has not been able to get temperatures down to below 15 degrees. It needs to be at 5 degrees, the ideal temperature to form the barrier.

TEPCO is currently dropping about 10 tons of ice and one ton of dry ice per day into the trenches surrounding the reactors. If temperatures drop enough and the ice wall starts forming, the plan is to reduce the daily ice dump to about four or five tons and install an additional four pipes to bring the total up to 23 pipes pumping coolant.

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Although workers will begin once again pouring chemicals and other materials into the trenches in hopes of lowering the temperature enough to achieve a full freeze, experts are not expecting any results for at least another two or more months.

Shocking news -- the clowns who were in charge of Fukushima when it went out of control can't manage its clean-up. I for one am shocked.

5 ( +8 / -3 )

Yes, the ice plan isn't working as hoped.

The tasks that need to be done sort and long term at Fukushima are so incredibly challenging that it seems overwhelming. You can't just walk away because it's too hard.

Sure, it's easy to complain about the TEPCO management that didn't invest in changes that could have prevented this, or reduced the scale, but that's old news. We can't change the past and whining about that after all this time doesn't do a thing to tackle the job at hand now.

If you have a better idea, how about telling us your plan? Whinging or trying to be clever doesn't solve anything.

-6 ( +4 / -10 )

If you have a better idea, how about telling us your plan?

Yes, I would suggest that they hire a company that has experience building ice walls. Here is one, called Arctic Foundations.

http://www.arcticfoundations.com/index.php/news/46-agency-wants-site-put-on-ice-alaskan-called-to-chill-radioactive-waste-pond

8 ( +9 / -1 )

Didn't we know all that before. So not really news! But at least they wasted again a couple of million or billion Yen tax-payer's money! And no, I don't have a better plan. The point, however, is that they should have thought about all this a long time ago. Besides consulting with experts around the world! There are people out there with better ideas and plans.

4 ( +4 / -0 )

Last year, a delegation from the IAEA visited the site and concluded that the risk of treating the water and letting it go out to sea was lower than the risks of trying to store it in tanks and treat it later. The argument is that even if all the waste from Fukushima were dumped into the Pacific, dilution would eliminate any radiation risks, especially to distant countries like the U.S. The ocean would be the safest place for the waste water. This is evident from continuous radiation monitoring in the ocean around Fukushima which shows extremely low levels of radiation, thousands of times less than background, and millions of times less than any EPA limits. Even though lots of contaminated water has entered the ocean from Fukushima, there has been little effect.

0 ( +1 / -1 )

@darnname: The government and TEPCO don't seem to be listening or trying to get any quality advice, even from experts around the world, so posting great ideas here wouldn't make a difference. But, "whinging or trying to be clever" helps spread the word about just how lame this disaster is being handled, and how it is being used to milk huge amounts of money from the taxpayers. If just one of the sheeple reads and becomes enlightened to the shenanigans going on, they might just tell their friends and so on. The more people that "whinge" the better the chances are that the government and TEPCO may be held accountable and actually start to behave reresponsibly. Believe me, if someone put up a foolproof, perfect solution to the Fukushima problems, here on this thread, there is zero chance the government would implement it, even if they read it.

5 ( +5 / -0 )

The argument is that even if all the waste from Fukushima were dumped into the Pacific, dilution would eliminate any radiation risks

That is your idea, not the IAEA's idea. They want the water to be treated first.

5 ( +5 / -0 )

Farmboy Sep. 24, 2014 - 08:22AM JS That is your idea, not the IAEA's idea. They want the water to be treated first.

Then I will ask you this question: why is a 19th-century technology the chosen path for securing the Fukushima nuclear power plant? A ‘subsurface cryogenic barrier’ may seem like a futuristic technology, but it’s actually an old one. Ice walls have been used in mining and construction since the 19th century. But their use for holding back contaminates and waste is more recent. The Fukushima ice wall will be huge, will cost about $400 million to emplace, and will require enough electricity to power 13,000 homes in Japan, or about $20 million a year, just to keep it frozen for the many years it will be needed.

1 ( +1 / -0 )

sfjp330,

My understanding is that once the wall completely freezes, the amount of power needed to keep it frozen drops dramatically. As to the comparative advantages of an ice wall, if they ever get it built, over a concrete wall, I really don't know... maybe they figure the concrete would eventually crack but the ice wall wouldn't.

2 ( +2 / -0 )

Sure, it's easy to complain about the TEPCO management that didn't invest in changes that could have prevented this, or reduced the scale, but that's old news. We can't change the past and whining about that after all this time doesn't do a thing to tackle the job at hand now.

darnname -- agree, but noting that the same folks who could not manage Fukushima are no match to solve the scope of this kind of disaster is absolutely fair, and is not "whining". Solving Fukushima will require courage, real smarts, creativity/thinking outside-the-box and foresight -- none of which TEPCO management has displayed. IMO the J-government should have cleaned house there when they pumped in billions into the clean-up/recovery and brought in the "best and the brightest". TEPCO management appears most concerned about managing PR and making a profit, not in truly leading this process.

1 ( +3 / -2 )

@farmboy

At least politically, ice wall may be the easier solution. The relative risks of the contaminated water, dumping into the ocean could easily be perceived as a morally irresponsible act. But adding on technological solutions could bury the problem deeper. If the ice wall encounter extended complications, the public will have only further reason to oppose nuclear and distrust the utilities.

1 ( +1 / -0 )

Once again, this is not the "Ice Wall" in the soil that is being developed to prevent groundwater entering the plant and getting contaminated. This is actually an attempt to freeze the water in the trenches under the plant, so allowing that contaminated water to be removed.

References:

Ice Wall - http://www.tepco.co.jp/en/decommision/planaction/qa_ice_wall-e.html Ice Wall vs. Trench Freezing project - http://www.tepco.co.jp/en/press/corp-com/release/2014/1237950_5892.html Trench project - http://www.tepco.co.jp/en/decommision/planaction/images/140620_01.pdf

1 ( +1 / -0 )

collect large amounts of radioactive particulate contaminated water and funnel it into trenches, freeze it, and then transport it to safe disposal sites elsewhere

WHERE? Isn't this always the question with nuclear waste -where to dispose it?

3 ( +3 / -0 )

Although workers will begin once again pouring chemicals and other materials into the trenches in hopes of lowering the temperature enough to achieve a full freeze, experts are not expecting any results for at least another two or more months.

It'll likely work great in January and February, followed by much head scratching as it fails as spring arrives...

3 ( +3 / -0 )

Jesus! ENOUGH already. Give it UP and use PROVEN technology!!! STOP wasting OUR money and stressing everyone out. TEPCO wants the 'ice wall' because guess what is needed to power it... QED. Am sick to DEATH of the incompetence, lies, deception and the theft of time, lives and money.

7 ( +8 / -1 )

The argument is that even if all the waste from Fukushima were dumped into the Pacific, dilution would eliminate any radiation risks,

There has been some random sampling of sea life up to 20 or 30 kilometers away from Fukushima 1, and what was found was negligent radioactivity in mid level fish but random spikes, up to around 10 times allowed limit for seafood, in bottom dwelling fish. "Random spikes" means not all bottom dwelling fish, just seeming random locations not necessarily closest to Fukushima 1. It was the website of the of the agency showing the raw data they had measured without much comment. Sorry I have lost the link and can't be bothered to find it now.

Although the sea is three dimensional, a possible explanation is that the pollutants become included in the bio-system which deposits them at the bottom not evenly but in unpredictable ways. Just like it was found that shiitake mushrooms far back in the mountains of Okutama, or green tea in Shizuoka had unsafe accumulations of radiation after the disaster.

I am not so worried about it spreading to the US, but I am quite concerned about local hard to detect concentrations and its ramifications for seafood.

2 ( +2 / -0 )

Star-Viking

Yes, the smaller version of an ice wall to freeze the cable trenches but if that is failing because TEPCO can't get the temp lower enough when what chances you think the bigger more expensive ¥30 billion ice wall is going to work, even though it has in other places like building subway tunnels in New York?

Much of the technology needed to deal with the nuclear disaster site is unproven and very expensive so the government needs to ensure its getting real value for its money being pumped in at a quicker rate than contaminated water is being frozen or pumped out?

6 ( +6 / -0 )

Yes, I would suggest that they hire a company that has experience building ice walls. Here is one, called Arctic Foundations.

Farmboy, go look at their website. Their installations are in places like Alaska and Kyrgyzstan that get very, very cold for a long portion of the year. That's not Fukushima, which doesn't get that cold.

The problem with the idea behind this solution has always been how to get it to work in a non-arctic or sub-arctic environment, hasn't it? And lo and behold, there's problems. I don't think it was a good solution in the first place.

0 ( +0 / -0 )

zichiSep. 24, 2014 - 11:09AM JST

if that is failing because TEPCO can't get the temp lower enough when what chances you think the bigger more expensive 30 billion ice wall is going to work

It will succeed almost surely. Freezing underground water is a proven technology in construction industry. I do not see any factor that would lead to failure, except the obstruction by some of the people who value money more than environment.

-3 ( +2 / -5 )

Zichi,

Star-Viking

Yes, the smaller version of an ice wall to freeze the cable trenches but if that is failing because TEPCO can't get the temp lower enough when what chances you think the bigger more expensive ¥30 billion ice wall is going to work, even though it has in other places like building subway tunnels in New York?

It's a different technology. The ice wall freezes water in the soil, a common technology. The trench project has to deal with flowing water, and so is more difficult.

2 ( +2 / -0 )

Months ago geological experts said it would not work. But they go ahead spend Tax payers money on something doomed to fail and now need to spend more money to benefit a corrupt network of grey companies while failing to solve the problem. Nuclear industry at its best.

1 ( +3 / -2 )

Cricky,

the article is inaccurate - they are not talking about the ice wall in the soil around the reactor buildings - they are talking about ice plugs in trenches under the plant.

1 ( +1 / -0 )

A reactor melts down at about 3000 degrees Celsius, keeping on heating for centuries. Stopping this with some ice ?? Japanese engineering...

-1 ( +3 / -4 )

A reactor melts down at about 3000 degrees Celsius, keeping on heating for centuries. Stopping this with some ice ?? Japanese engineering...

I don't think you've left any point left unmissed, but at least you're angry about it.

3 ( +3 / -0 )

A reactor melts down at about 3000 degrees Celsius

No, try closer to 1200.

keeping on heating for centuries

Not really. Once the fuel melts the reaction greatly slows or stops and the temperature rapidly drops.

Stopping this with some ice ??

No. The ice wall is to stop water flowing into and out of the reactor buildings. At the distance the ice wall is being built there is about zero heat from the melted fuel.

Japanese engineering...

Maybe understanding what is actually being done would help people understand the engineering.

1 ( +2 / -1 )

Yesterday I watched a TEPCO video taken at the No 3 reactor and went by largely without comment. The camera enters the floor in the damaged NW corner which locates the PLR-MG, or Primary Loop Recirculation System Motor Generator which probably went on fire at the time of the reactor explosions.

In the video smoke or steam? can clearly be seen.

https://www.youtube.com/watch?v=aMotB0hGxXk

6 ( +6 / -0 )

zichi,

I see a reflection related to light on the lens, but not smoke or steam. What I'm looking at changes when the camera moves one way and changes back when it goes the other way. It's kind of grayish, but I don't think it's smoke. At what time on the video do you see what you're seeing?

0 ( +1 / -1 )

"It needs to be at 5 degrees, the ideal temperature to form the barrier." I believe I see the problem here. In the reality-based world, water freezes at 0 degrees. As Mike notes, maybe understanding what is actually being done would help people, particularly those who work for TEPCO, understand the engineering.

1 ( +1 / -0 )

I bet the freezing point of contaminated water is something less than 0 C. But I am no physicist.

Also, I wonder if these engineers have ever heard of the season called "winter". The low temperatures during that time is really a great help when trying to create ice.

0 ( +0 / -0 )

Farmboy,

You are probably right with your conclusions but I thought it looked like smoke/steam at about 18:38?

2 ( +2 / -0 )

You had me at "TEPCO having trouble..." Enough said.

2 ( +2 / -0 )

zichi,

I see what you're looking at, but the grey area seems to extend in front of the rope as well in a line... I think smoke would move more, and show more variation. Good to know someone is checking on those folks, though ... can't depend on them..

2 ( +2 / -0 )

This is what happens when you let the clowns run the circus! This technology has been in use for many years in many different industries. Admittedly, Fukushima does have a sub-tropical climate that is causing the difficulties, but they have been stuffing around for six months and still are no closer to achieving any sort of success. They are dumping ten tons of ice into it every day. As the ice melts it mixes with the contaminated water they are trying to stop and drains into the great Pacific Ocean nuclear waste dump. It just seems that everything they do is one step forward and three steps back. If they are not competent in achieving the frozen wall they should either replace the wombats in charge and get someone in ther that can do the job or stop wasting billions of yen and find an alternative.

0 ( +1 / -1 )

Didn't even need to read the article after reading the headline. TEPCO failing at another one of their harebrained ideas... An ice wall no less. Gee, there's a surprise.

0 ( +0 / -0 )

Disillusioned,

the article is inaccurate - they are not talking about the ice wall in the soil around the reactor buildings - they are talking about ice plugs in trenches under the plant.

1 ( +1 / -0 )

I predict success in January!

0 ( +0 / -0 )

It's called underground water frozen method, actually Japan has some best companies/ engineers on earth for this sort of technique, I don't understand why these experts didn't cooperate with TEPCO for this case?? think about it!

0 ( +0 / -0 )

Meanwhile Fukushima rattles off a 5.6 mag earthquake!

3 ( +3 / -0 )

At Mike O'Brian Melt down temperature is around 2850 degrees Celsius. Good steel has a melt point at about 1500 degC. So with your 1200 degC (melt point of zirconium rods is about 1800 degC, which melts after the control rods) you assume everything is nicely in the reactor. Good to know the IAEO guys are wrong. Let's asume IAEO is right and the material is through the reactor and maybe 2 meters into foundation. What happens to the water that possibly flows through the containment? Heating up and melting the ice wall. Cool down time of elements is normally considered 10years before permanent storage.

0 ( +2 / -2 )

JAEA actually picked the ice scheme for Fukushima Daiichi.. Since they are in charge of the Governmental Decommissioning JAEA chose the buddies at Kajima Design Corp. plan... Complete Entombment of Daiichi would have been a better Idea but it's not very expensive to do so Kajima Corp would not have made a big profit

0 ( +0 / -0 )

It is still ongoing disaster. Of course Tepco is not going to ask for international help, neither Jaapanese government. In the mean time out of money and ideas? But don't worry everything seems to be under control.

2 ( +3 / -1 )

I bet the freezing point of contaminated water is something less than 0 C

And I bet that the something less than 0C is maybe as low as -2C (the freezing temp of seawater). Insignificant when compared to the -15C to -35C of the chilled calcium chloride brine.

@Ghost rider

you assume everything is nicely in the reactor

I assume no such thing.

Cool down time of elements is normally considered 10years before permanent storage.

No actually it is more like 3 or 4 and we are 2.5 years since the accident. Also the heat generation drops rapidly in the first few months. Of course water flowing by/through the melted cores will be heated, but with the flow rate being measured in tons of water per day I would be willing to bet that the temperature increase in the water is less than 5 degrees.

0 ( +0 / -0 )

When spent nuclear fuel is removed from the reactors it spends five years in the cooling pool before being considered cool enough to move to another pool and then casks or whatever.

0 ( +1 / -1 )

When spent nuclear fuel is removed from the reactors it spends five years in the cooling pool before being considered cool enough to move to another pool and then casks or whatever.

Nope. Some nuclear plants do hold it in pools for 5 years. Heck some hold it for 10 years or longer in the pools. But it is cool enough after 3 years for movement to dry cask storage.

2.As the pools near capacity, utilities move some of the older spent fuel into “dry cask” storage. Fuel is typically cooled at least 5 years in the pool before transfer to cask. NRC has authorized transfer as early as 3 years; the industry norm is about 10 years.

http://www.nrc.gov/waste/spent-fuel-storage/faqs.html

The decision is mostly an economic one. The fuel pool is already paid for and has to operated to keep the newest spent fuel cool, leaving older already cooled fuel in the pool essentially costs nothing. But moving it to casks requires buying the casks and taking the time to actually move the fuel. Leaving the fuel in the pool, even if no longer required, is cheaper and easier. The movement is often deferred until the fuel pool is approaching capacity forcing the nuclear plant to remove the oldest stored spent fuel to create space for spent fuel from the next refueling.

0 ( +0 / -0 )

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