Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[jlduh]

It'll hold only while there is something ~solid beneath, and it can do nothing with any water coming from outside the sprayed area.

I'm worried and expecting problems.

Plus, as said in the article, the debris make the opeartion very complex. If you think about the developped surface of all the debris lying one over the others in a big pile of mess, this surface is huge, and to be covered the glue has to go into all these cavities below the steel mess to avoid being wash by the heavy rain, which is probably less viscous.

So for sure it will reduce for some time the amount of dust released and washed away but I woud be very interested to now the real mid-term efficiency of this process.

Covering it with a plastic protection will be more effective, but that's an other story to do it...

EDIT: i don't know if this product is related to this japanese patent (quite surprisingly, it seems to contain boron, even if it was developped for asbestos antiscattering):

http://pat365.com/patent/patentContent.jsp?pID=JP2010019051&patType=%E7%A1%BC%EF%BC%9B%E5%85%B6%E5%8C%96%E5%90%88%E7%89%A9%26nbsp;Boron%26nbsp;Compounds%26nbsp;thereof%26nbsp;#

 

[elektrownik]

new picture of unit 3 with iaea team: http://www.tepco.co.jp/en/news/110311/images/110527_3.jpg
On the left we can see 2nd fuel machine, and big crane in center

 

[GJBRKS]

new picture of unit 3 with iaea team: http://www.tepco.co.jp/en/news/110311/images/110527_3.jpg
On the left we can see 2nd fuel machine, and big crane in center

Close-up of area :

http://inkers.nl/uploads/reactor-3.JPG

 

[Rive]

new picture of unit 3 with iaea team: http://www.tepco.co.jp/en/news/110311/images/110527_3.jpg
On the left we can see 2nd fuel machine...

https://www.physicsforums.com/showpost.php?p=3293994&postcount=6467" :-)

 

[zapperzero]

Plus, as said in the article, the debris make the opeartion very complex. If you think about the developped surface of all the debris lying one over the others in a big pile of mess, this surface is huge, and to be covered the glue has to go into all these cavities below the steel mess to avoid being wash by the heavy rain, which is probably less viscous.

Which is why they will only really spray the walls and other reasonably flat surfaces.

 

[PietKuip]

this document might be of interest in regard to recriticality in BWRs
http://bit.ly/mpxlJB

source:
http://www.sciencedirect.com/science/article/pii/S0029549301003922

This article considers the case where electrical power and water is restored during the time window between the melting of the control rods and the melting of the fuel rods.

It does not seem that something like that occurred at any of the Fukushima reactors.

 

[jlduh]

https://www.physicsforums.com/showpost.php?p=3293994&postcount=6467" :-)

yes, it has already been discussed here and this looks like the machine that tensions the studs, this is even clearer with this view. This is what Jim was identifying as the RPV cover, but this is not.

We have also a better view over the yellow part that Jim proposed to be the containment cover but to me, it seems more to be a concrete part with some clear (and maybe yellow?) color...

 

[jim hardy]

@ Tonio --

THANK YOU for your interest! And your kind reply.

I looked for your "yellow tank" on an aerial photo of R3 and I believe I have found it. I compared its dimensions with the yellow reactor cap visible in R4. It seems to have about half to two-thirds of the size of the R4 cap, thus it seems to be something else.

we are real close together, Mr Tonio. I am looking NORTH of that cockeyed vent pipe on roof, you are south. Right hand edge of your rectangle goes over my object.

Here it is on a March 16 photo, very slightly different angle.. I put a rectangle around it like you did. Note relation to vent pipe.
It gets obscured in later photos. Small wonder with all the rain and smoke , not to mention the aftershock tremors of 18th.

yours is much higher quality than mine, i don't have knack yet.
Mine is in the zipped folder at
http://cryptome.org/eyeball/daiichi-npp3/daiichi-photos3.htm
and you have to unzip the folder referenced at top of that file
where it says

The 31 originals full-size: http://cryptome.org/eyeball/daiichi-npp3/daiichi-photos3.zip (30MB)

it unzips to a 1.02 meg jpg and i don't know why its so blurry. yours is sharper yet less bytes. After unzipping it's got name aerial-2011-3-18-14-50-0.jpg, one of ~30 photos. I made a folder for them.


do you have the link for your photo?

In the photo above one can plainly see the uncovered hole where reactor plug oughta be.
Later ones look like the hole is covered by crane. I blame that on aftershocks of 18th i think they were, do i recall a 5.5 ?

 

[jlduh]

new picture of unit 3 with iaea team: http://www.tepco.co.jp/en/news/110311/images/110527_3.jpg
On the left we can see 2nd fuel machine, and big crane in center

One is Philippe Jamet, Head, Division of Nuclear Installation Safety at IAEA.
http://www.iaea.org/newscenter/multimedia/videos/safety/npp/jamet/index.html

By the way everything he is saying in this video is a premonition, several month before, of what occurred at Fukushima... The analysis is perfect.

But let's talk about this in the political thread: https://www.physicsforums.com/showthread.php?p=3325284#post3325284

 

[jim hardy]

This article considers the case where electrical power and water is restored during the time window between the melting of the control rods and the melting of the fuel rods.

It does not seem that something like that occurred at any of the Fukushima reactors.

piet the link took me to a place that offers it for $31.50

i downloaded a document by same title here, i think it's a public document
http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/31/025/31025624.pdf

think it might be same one?

for another forum's discussion of recriticaliy , peruse
http://tickerforum.org/akcs-www?singlepost=2541030
it's by a layman but references a couple official documents, and gives links

oops i was going to stay quiet.

over and out for 24.

 

[SteveElbows]

In the photo above one can plainly see the uncovered hole where reactor plug oughta be. Later ones look like the hole is covered by crane. I blame that on aftershocks of 18th i think they were, do i recall a 5.5 ?

Come off it. There is no evidence that the crane & its supporting structure fell later. Pay even half as much attention to photos that actually show stuff clearly as those that do not, and pretty much all of the features that interest you vanish.

Take for example your recent posts about the rubble on north side of reactor 3 building. There were already a number of other photographs which have enabled us to identify some things more clearly, things that don't match your analysis. And todays photos with IAEA delegation and reactor 3 provide further evidence that what you think you might see in the low res shot is not actually there, and no amount of internet discussion will change that. No reactor or containment caps.

 

[~kujala~]

don't forget that there is a rainwater collection system for the plant, we don't know how this system is designed and how many outputs towards the sea there are, but I'm pretty sure this goes to the sea anyway because it is not supposed to be radioactive in normal conditions

Part of rainwater goes also into the same sub-drain pits where groundwater goes through vertical shafts, this is how I have understood this picture (sorry some text only available in Finnish):
http://varasto.kerrostalo.huone.net/salaojat_2.png
(Edit: It depends on whether the vertical shaft has open or closed top.)

As for the area outside buildings I have no clue where it is going. BTW I read somewhere that in modern buildings you should never direct groundwater and rainwater into the same pits as the picture above suggests that is happening in Fukushima.

When the basements are filling in with water, the differential is reducing and eventually, this differential can be inverted if water level inside basement becomes higher than water table level outside. Then the flow will invert also, and so leakage from basement towards watertable can happen (with contamination).

So this might indicate that it would be anyway a good idea to pump as much water from the basements as possible to keep the flow of water outside in.

I still think they should calculate some conservative worst-case scenario for all water that could accumulate in the buildings/sub-drain pits. This way there would be no more sudden surprises if the level of water would be "still rising". Instead they could say that water level is rising "as expected".

 

[AntonL]

new picture of unit 3 with iaea team: http://www.tepco.co.jp/en/news/110311/images/110527_3.jpg
On the left we can see 2nd fuel machine, and big crane in center

It looks like a pre-cast construction method was used for the reactor building, at least for the upper part. That would explain why the columns got toppled that easily.

 

[AntonL]

Gundersen Gives Testimony to NRC ACRS http://vimeo.com/24312973

 

[SteveElbows]

Did some detail get lost in the drama of reactor 3's temperature rollercoaster this month?

I noticed for quite some time that TEPCO updates made it sound like the additional water via the reactor feedwater system was part of a plan to stop using the fire extinction system piping. But as they were clearly having issues trying to bring the temperature under control at the time, I wasnt sure if this was just spin. However, since the various reductions in water injection rate that have taken place recently have targeted the fire line, to the extent that water rate is now down to just 2 m3/h via that particular line, it seems they really are swapping over and this was not just an exercise in getting as much water as possible into the reactor to put the brakes on soaring temperatures.

Do we know if TEPCO have said why they wanted to switch lines? Do we know at what height water emerges from the fire line as opposed to the reactor feed line? Its possible that they think fire line was doing a poor job of cooling 3, or are there other reasons why a switch was more desirable, eg for the longer term?

Example of what TEPCO say about this stuff in updates:

-At 4:53 pm on May 12, as a part of work to switch the water injection
line to the reactor from the fire extinction system to the reactor feed
water system, we started water injection through the reactor feed water
system in addition to through the fire extinction system.
-At 8:52 pm on May 26th, we changed the rate of water injection to the
reactor through the fire extinction system piping arrangement from
approximately 3 m3/h to approximately 2 m3/h.
-The current rate of water injection is approximately 2 m3/h through the
fire extinction system piping arrangement and approximately 13.5 m3/h
through the reactor feed water system piping arrangement .

From http://www.tepco.co.jp/en/press/corp-com/release/11052710-e.html

 

[westfield]

@ Westfield:

snip >

I believe the yellow "tank" you pictured in your unit 4 photo IS the reactor containment cap..that's just where it sits in the drone photo, if I'm not turned around, in NW corner.

<snip

The yellow containment cap cannot be seen in that particular R4 image, the intact concrete walls hide it. The tank item is below the refuelling floor level. http://i1185.photobucket.com/albums/z360/fukuwest/misc/R4yellowtankyellowcapaerial-2011-3-30-3-20-15.jpg" - anyway, thankfully now there is finally a nicer picture of the NW corner of RB3 which makes all this redundant.

 

[SteveElbows]

Actually let me rephrase that. I mean it seems obvious that they made all these changes in response to the soaring temperatures, I just wondered if the fire line has now been identified as the culprit, eg it stopped being able to cool the reactor well towards the end of april, as opposed to something new happening in the reactor which caused it to require more cooling. I guess if they stop using the fire line altogether, which seems likely, and then reduce the other lines rate to around what used to be enough to keep reactor 3 temperatures sort of stable, we may have a clearer idea of whether this is possible. I don't think we can really tell whether the boron injection they did around may 15th made any difference because temperatures had already started to fall by then as a result of increased injection of water/using more effective piping.

 

[jim hardy]

Westfield, SteveE

thanks that is what I've been looking for, good rebuttal from actual photos...
i completely missed your yellow tank on floor below..

hope more hi quality pics are forthcoming soon.

 

[SteveElbows]

I don't think we can really tell whether the boron injection they did around may 15th made any difference because temperatures had already started to fall by then as a result of increased injection of water/using more effective piping.

Actually I should say that some of the temperatures had started to fall by then, others did not fall until after the boric acid. But there was so much else going on at the time with changing flow rates that things remain too murky for me to draw any conclusions.

 

[etudiant]

Is there any fundamental reason why the excess water in the plant could not be transferred to large tankers as a short term measure?
Even if the ships are scrap after the service, it would be cheaper than having the water overflow and contaminate much of the coastal shoreline. Plus these tankers are double bottomed and pretty watertight,
so spillage would not be a serious concern.
There should at least be a fallback plan if the Areva decontamination effort runs into delays.

 

[SteveElbows]

Westfield, SteveE

thanks that is what I've been looking for, good rebuttal from actual photos...
i completely missed your yellow tank on floor below..

hope more hi quality pics are forthcoming soon.

I hope so too, although I suspect there are very few angles from which we will actually stand a chance of learning anything crucial. Since unit 4 fuel pool fears receded to some extent, reactor 3 is the only likely candidate where images from outside the building could tell us much. And the area of real interest is going to be hard to see unless they actively decide to get a camera closer to that area when lighting conditions are at their best. And even then we'll probably just get a clearer view of crane etc debris. When disagreeing with your image analysis, I have often wanted to post images of the area that paint a different picture, but in most instances the quality of these is no better than the ones you've used, so I am just exchanging one mystery low-res blob for another, less exciting one.

In regards to why I sounded confident that the crane didnt fall later, its a bit hard to imagine it falling later due to the way the crane structure has fallen roof on top of it on the other side of the building. At least in the IAEA picture we get another look at the shadowy crane debris, get a vague sense of detail to a part of it that's nearer to area above the reactor, an area that tends to remain elusive/looks quite different on every different set of photo/video evidence we have. This part of the crane is also a contender for the snaggle-toothed thing you've been interested in, although there are a range of other things that could be as well.

 

[MadderDoc]

<..>
In regards to why I sounded confident that the crane didnt fall later, its a bit hard to imagine it falling later due to the way the crane structure has fallen roof on top of it on the other side of the building.

I'd say it even stronger: The thought that the crane fell later has no basis in any evidence whatsoever.

At least in the IAEA picture we get another look at the shadowy crane debris, get a vague sense of detail to a part of it that's nearer to area above the reactor, an area that tends to remain elusive/looks quite different on every different set of photo/video evidence we have. This part of the crane is also a contender for the snaggle-toothed thing you've been interested in, although there are a range of other things that could be as well.

But, I'm afraid there is no mystery monster lurking there either, snaggletoothed or not :-), seeing whatever the angle and zoom-level, no pixels indicate the presence of anything significant there but the overhead crane.

 

[MiceAndMen]

Take for example your recent posts about the rubble on north side of reactor 3 building. There were already a number of other photographs which have enabled us to identify some things more clearly, things that don't match your analysis. And todays photos with IAEA delegation and reactor 3 provide further evidence that what you think you might see in the low res shot is not actually there, and no amount of internet discussion will change that. No reactor or containment caps.

If we could get a new set of high-resolution photographs of the plant we could probably eliminate 2/3 of the ongoing speculation. Maybe TEPCO or the IAEA will surprise us soon.

 

[AntonL]

A member of the IAEA fact-finding team in Japan examines an earthquake- and tsunami-damaged structure near the seawater intake area at Tokai Daini Nuclear Power Plant on 26 May 2011.

To those that believe unit 4 is leaning - this is what a leaning building looks like

 

[Sabbatia]

Okay, be kind to me. Remember, I'm an accountant and a female at that. My gut instinct sees a mess and wants it cleaned. Is the reason they haven't gotten a crane in there and lifted off some of the debris because it's too radioactive and they would have to use a cutting torch to do it?? Those buildings remind me of my desk at work, and I like to get the big stuff off of it first so I can assess the situation.

 

[intric8]

To those that believe unit 4 is leaning - this is what a leaning building looks like

Touche. Some people have trouble making reality conform to their thesis.

 

[swl]

this is what a leaning building looks like

Another example for you.

The foundation may, or may not be leaning, but the No.4 building is leaning in numerous directions and is in a dangerous state of disrepair.

 

[Cire]

Okay, be kind to me. Remember, I'm an accountant and a female at that. My gut instinct sees a mess and wants it cleaned. Is the reason they haven't gotten a crane in there and lifted off some of the debris because it's too radioactive and they would have to use a cutting torch to do it?? Those buildings remind me of my desk at work, and I like to get the big stuff off of it first so I can assess the situation.

I brought this up many weeks back. An overhead crane system could lower shears to cut away the debris above the reactors and move it by cable to a holding area. I suspect it's just not a priority at the moment.

 

[Astronuc]

Okay, be kind to me. Remember, I'm an accountant and a female at that. My gut instinct sees a mess and wants it cleaned. Is the reason they haven't gotten a crane in there and lifted off some of the debris because it's too radioactive and they would have to use a cutting torch to do it?? Those buildings remind me of my desk at work, and I like to get the big stuff off of it first so I can assess the situation.

At this point, they would be trying to minimize exposure and contamination. They would need a place to put the material removed from the damaged containment buildings. I believe the plan is to cover Units 1-4, and continuing working the decontaminate the facilities.

 

[jim hardy]

. When disagreeing with your image analysis, I have often wanted to post images of the area that paint a different picture, but in most instances the quality of these is no better than the ones you've used, so I am just exchanging one mystery low-res blob for another, less exciting one...
...This part of the crane is also a contender for the snaggle-toothed thing you've been interested in, although there are a range of other things that could be as well. ..

So you are in the same boat as me? Irresolute pictures?
I thought sure somebody would counter with higher quality photos. Believe me if had better ones i'd have used them, furthermore the question might not have even come up.

I do appreciate your good natured replies. In some forums (fora?) the denizens resort to flaming one another. That we can have civil exchange is the attraction here.

Somebody said "A discussion is an exchange of knowledge, an argument is an exchange of ignorance."

Mice & Men also said it well in his blog entry

In the instant case there has been comparitavely little information officially released that would enable outside observers (us, experts and amateurs alike) to eliminate various paths through the fault tree. A lot of information that has been released is contradictory and subject to reversal soon after...

and Borek confirmed with

Yes, in the Fukushima thread we allow speculation - as long as it is physically sound - as at this stage that's the best that can be done.

that's why i started with photographs and industry reports and always gave links to source..
it is easy to holler , what is difficult is to build a foundation and remain willing to cast it aside if it crumbles.

Also that's why i didn't post a photo of "Snaggletooth" here. Because so far as i can tell ALL pictures of him originate from that one helicopter video at
http://www.youtube.com/user/modchannel#p/a/u/0/ZKFGavZ_rf4
and i promised to not post unsupported gibberish here. Single source in this environment is unsupported, in my book.

well i just found another TEPCO helicopter video that leans toward your contention that Snaggletooth may be a part of the crane. I had never seen it before a few minutes ago. well a couple hours now.
and my fundamental rule is use nothing that's not cross checked against at least one other source.

So here's how to get to that video. It's from the TEPCO site so should be safe.

at TEPCO press site,
http://www.tepco.co.jp/en/news/110311/index-e.html#anchor1103
look for this text and click it

Photo of Reactor building of Unit3-4 at Fukushima Daiichi Nuclear Power Station by remote-controlled mini helicopter
(Video on April 10th, 2011)

That'll open this link which offers to load and unzip the file
http://www.tepco.co.jp/en/news/110311/images/110411_1f_14.zipso unzip it to a folder you can find (i have trouble with that).. it makes a short video

play the video and stop it at second 41
you'll get as good a view i have seen looking down between crane rails into refueling cavity BUT from opposite direction of that Youtube video.
would post a pic if i knew how to frame grab.Thanks to you guys i got a second photo of Snaggletooth's area from another angle. And to me it looks a lot less worrisome.

Have a look at that TEPCO ..0411 video and see what you think.

here's snaggletooth, from a frame grab off that youtube at second ten. it also shows at three.. A friend made and sent it to me
same crop repeated side by side, left highlighted right as received.

As you see it looks scary, like an open vessel with irregular top.
But i don't think it fares well on the cross check (against Tepco 0411 vid), could well be a crane part. Looks awfully tall.

So i am back to waiting patiently for TEPCO to release better photos of that area.
if you have any i missed please share.

Thanks,
old jim

 

[Bandit127]

Some new info on Tepco's site.

Press Release (May 28,2011)
Submission of Reports about the study regarding current seismic safety and reinforcement of reactor buildings at Fukushima Daiichi Nuclear Power Station (1)

The article links to a summary in English, but the full report is available in Japanese further down.
http://www.tepco.co.jp/en/press/corp-com/release/11052801-e.html"

Also, Bloomberg is carrying a story about a typhoon that might pass over tomorrow. (Let's hope it passes on by instead).
http://www.bloomberg.com/news/2011-05-27/typhoon-strengthens-may-hit-fukushima-nuke-plant.html"

 

[jlduh]

As I calculated it some posts ago, rain is going to be a big contributor to the leaks towards ocean... 44 000 tonnes forecasted to fall on the 1000m x 400m area i 've taken into account by the next 3 or 4 days (the finishing bit of the Songda Supertyphoon). No need for Areva to wash the mess, Songda will do it for free...

http://www3.nhk.or.jp/daily/english/28_14.html

Rain likely to induce more radioactive leaks
The operator of the damaged Fukushima Daiichi nuclear power plant says it is closely monitoring contaminated water levels in the facility as heavy rain is forecast next week.Tokyo Electric Power Company is continuing to inject water to cool reactors. As a result, the level of highly radioactive water around reactor buildings is rising.

The company is concerned that contaminated water in the basement of reactor buildings and nearby tunnels may overflow and seep into the ground and the sea.Rain is forecast on Sunday and Monday because of an approaching typhoon.

As of Saturday morning, the water height is 57.6 centimeters below ground level around the Number 2 reactor and 43.1 centimeters below ground level for the Number 3 reactor.

 

[zapperzero]

Another example for you.
The foundation may, or may not be leaning, but the No.4 building is leaning in numerous directions and is in a dangerous state of disrepair.

You want to worry about something structural?
Here:

That beam seems supported on... nothing really.

One other thing that caught my eye is this big steel member thing

that seems to have fallen inwards. I can only see that happening if it got twisted out of place, then fell.

It's also kind of interesting because it's got a big chunk of insulation foam hanging off it, with strips of some pink sheeting on the outside. Maybe that could help us find its initial position? What's on that level that needs massive thermal insulation?

Both are crops from
http://www.tepco.co.jp/en/news/110311/images/110527_3.jpg

 

[zapperzero]

No need for Areva to wash the mess, Songda will do it for free...

And the contaminated water will flow into the sea and form dangerous puddles on the plant grounds and TEPCO will apologize and halt operations for a week or so till they figure out what to do about it...

 

[tsutsuji]

Tokai II Nuclear Power Plant (02810451) by IAEA Imagebank, Members of the IAEA fact-finding team in Japan visit seawater intake pumps at Tokai II Nuclear Power Plant on 26 May 2011.

Picture location on Google maps : http://maps.google.com/maps?t=h&q=3....466885,140.609674&spn=0.000678,0.001515&z=20

Asahi diagram : http://www.asahi.com/photonews/gallery/infographics/110330_toukai2.html

Wikipedia : http://en.wikipedia.org/wiki/Tōkai_Nuclear_Power_Plant

(my previous post about Tokai NPP : https://www.physicsforums.com/showthread.php?p=3317681&highlight=Tokai#post3317681 )

The plan for inpection No. 25, which started on May 21st, and will take 6 months : http://www.japc.co.jp/tokai/teiken/tokai2/25/index.html (in Japanese), including :

Diagrams showing the adding of a spare seawater pump to replace any of the 3 seawater pumps that send seawater to the 3 diesel engines : http://www.japc.co.jp/tokai/teiken/tokai2/25/tenpu-1-10/tenpu-6.pdf ; or those that cool the residual heat removal system : http://www.japc.co.jp/tokai/teiken/tokai2/25/tenpu-1-10/tenpu-7.pdf

A diagram showing the residual heat removal system, providing context for a work concerning seawater piping : http://www.japc.co.jp/tokai/teiken/tokai2/25/tenpu-1-10/tenpu-5.pdf

 

[MadderDoc]

We should take up a collection to pay for another round of hires photos from the Air Photo Service guys. Their photo survey on March 24 was over two months ago and we haven't seen a whole lot of new pictures from the air since then.

Certainly I would not be pale about contributing, I love air photos. However unless such photo coverage were to be exceptionally tight I'd probably still be left with questions about unit 3 that are more rationally answerable by the people on the ground.

I would really like to hear about Tepco's observations on the ground as regards which equipment pieces and fragments that were spat out by unit 3, about Tepco's thoughts about those observations, and about any conclusions Tepco may have made as regards the mechanism of the spectacular explosive event at the unit. I can't believe that Tepco would have nothing to add to the zillionth daily repeat in their press releases , that "Explosive sound and white smoke were confirmed at approximately 11:01am on March 14. It was assumed to be hydrogen explosion."

 

[tsutsuji]

The foundation may, or may not be leaning, but the No.4 building is leaning in numerous directions and is in a dangerous state of disrepair.

Concerning the repairs, page 17 of the Progress Status of Roadmap released on May 17th : http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110517e5.pdf said the steel pillar installation was supposed to start on May 23rd.

I wonder if the steel pillar is still needed after the seismic analysis has concluded "we estimate it has the adequate safety" : http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110528e1.pdf page 2.

 

[htf]

Those buildings remind me of my desk at work, and I like to get the big stuff off of it first so I can assess the situation.

I do understand you. These buildings offend my eyes and make me scream: please, remove these ruins! And Tepco would certainly be keen on making these stigmata vanish but that doesn't solve their problem. Their top priority is to establish a cooling system for the reactors and prevent further releases of radioactivity. Once they have stabilized the reactors they have to come up with a solution similar to the sarcophagus of Tchernobyl. The reactors are not at all stabilized at the moment and compared to the Soviets the Japanese are extremely slow - we all know which price the Soviets had to pay.

Deconstruction of the site will be a project of the next decades. They have to wait for a long time until radiation levels go down enough. Look at Windscale: this was a British reactor for military purposes which caught fire in 1957. Now they are starting deconstruction.

 

[clancy688]

As I calculated it some posts ago, rain is going to be a big contributor to the leaks towards ocean... 44 000 tonnes forecasted to fall on the 1000m x 400m area i 've taken into account by the next 3 or 4 days (the finishing bit of the Songda Supertyphoon). No need for Areva to wash the mess, Songda will do it for free...

Let's assume all speculation about the leaning of Unit 4 are true. Then washing out of radioactivity isn't the biggest problem IMHO.

Why is Unit 4 leaning? I don't think that the hydrogen explosions are at fault, at least not entirely. Damage is only in the upper part of the building, but leaning suggests that there's something wrong with the foundation. So the Tsunami probably damaged the building's foundation or washed away / drenched the earth. Plus the cooling water which's further adding to the mud. Basically, the Unit is leaning because it's standing not on solid earth, but a muddy field.
But what happens if there's a typhoon coming, bringing heavy rainfalls with it? Could it further damage the underground to that point, that there's some kind of an Earth slide resulting in Unit 4 collapsing?

Weather forecasts for Fukushima (the town, didn't find anything for Okuma) predict 60 l/m² during the next two days.

 

[AntonL]

TEPCO: Tainted water disposal may cost $650mln
http://www3.nhk.or.jp/daily/english/28_03.html

$650,000,000- for a plant that is delivered in 6 weeks + the consumables
For that sort of a price I hope Tepco has guarantees from Areva

Do we know anything about the process?

 

[biffvernon]

Damage is only in the upper part of the building, but leaning suggests that there's something wrong with the foundation. So the Tsunami probably damaged the building's foundation or washed away / drenched the earth. Plus the cooling water which's further adding to the mud. Basically, the Unit is leaning because it's standing not on solid earth, but a muddy field.

Continuing the assumption that it is leaning, we really can't jump to the not on solid earth, but a muddy field assumption. If there is a tilt it is just as plausible that the very solid rock foundation is less horizontal than it was before the earthquake. That's kind what happens in earthquakes. Loads in the building may not be quite in the designed direction but that could be the least of the worries. There's a famous tower in Pisa that manages fairly well at a jaunty angle.

 

[imandylite]

Not Much comeing out of TEPCO these days

But they have released a video this week

Spraying Reactor unit 1

https://www.youtube.com/watch?v=WMo_kq0cjJ8

 

[zapperzero]

Let's assume all speculation about the leaning of Unit 4 are true.

Let's. But until we test this assumption, there's no reason to go further. You know that saying...

 

[MadderDoc]

New video handout, antidust spraying at unit 1 turbine building, now with yellow spray.

 

[~kujala~]

But what happens if there's a typhoon coming, bringing heavy rainfalls with it? Could it further damage the underground to that point, that there's some kind of an Earth slide resulting in Unit 4 collapsing?

These buildings are earthquake-proof to the extent they were designed, this also means that foundations should be capable of handling some kind of slides every here and there. For how much, that is a completely different question.

A couple of techniques used to protect foundations from differential settling:

In designing structures for earthquake resistance, one should find tie beams underground between the columns to transfer weight from one footing to another in the case of differential settling. Another option is to build a so-called floating foundation, where the building is essentially like a ship. The ground may move, but the building will move with it and the building internals (i.e. walls, columns, pipes, etc.) hopefully will not have much movement relative to each other. I think the latest design from Areva uses a floating foundation.

What he didn't mention is that designing a floating structure is significantly more expensive.

http://ex-skf.blogspot.com/2011/05/fukushima-i-nuke-plant-ground-may-have.html
(comments)

 

[Astronuc]

TEPCO: Tainted water disposal may cost $650mln
http://www3.nhk.or.jp/daily/english/28_03.html

$650,000,000- for a plant that is delivered in 6 weeks + the consumables
For that sort of a price I hope Tepco has guarantees from Areva

Do we know anything about the process?

I think it was mentioned elsewhere in this or one of the other threads. I suspect it is similar to the processes used in the recycling process, since they have to recover a variety of fission products and fuel particles. Ostensibly, they would tailor the process according to assays of the liquids.

Here are examples of radwaste treatments
http://www.wmsym.org/archives/2008/panels/56-2.pdf

 

[MadderDoc]

Attached photo mosaic of frames from video of the unit 3 spent fuel pool. Particularly eye-catching, imo, is the apparent gross damage to the steel liner of the pool. I find it difficult to imagine how a hydrogen explosion at the service floor could have left the pool liner in this condition.

 

[NUCENG]

This ought to keep us busy for a few hours:

http://dels.nas.edu/resources/static-assets/nrsb/miscellaneous/SekimuraPresentation.pdf

 

[Rive]

Attached photo mosaic of frames from video of the unit 3 spent fuel pool. Particularly eye-catching, imo, is the apparent gross damage to the steel liner of the pool. I find it difficult to imagine how a hydrogen explosion at the service floor could have left the pool liner in this condition.

I'm not sure that it's the liner of the pool. Back in the days of the big pixel-huntings there was several tries to match various floorplans of service floors with the photos but IIRC it's still undecided if the FHM is there on the south end of the pool (covered with rubble and beams from the roof).

 

[fluutekies]

TEPCO: Tainted water disposal may cost $650mln
http://www3.nhk.or.jp/daily/english/28_03.html

$650,000,000- for a plant that is delivered in 6 weeks + the consumables
For that sort of a price I hope Tepco has guarantees from Areva

Do we know anything about the process?

I think it was mentioned elsewhere in this or one of the other threads.

https://www.physicsforums.com/showpost.php?p=3267742&postcount=4952
The pdf document: http://www.osti.gov/bridge/servlets/purl/93598-H1kI7u/webviewable/93598.pdf

I've designed & operated an inorganic wastewater treatment unit for some years: the volumes are not the problem, but the chemical behavior of the components.
The principle is very simple: add chemicals which form (nearly) insoluble precipitates or form precipitates which adsorb or incorporate soluble ions.

In practice it will be a multi-stage process due to pH and redox-behavior. As the solubiltyproducts of the involved components are not zero, the purification is never perfect.

A typical treatment for e.g. Sr²⁺ would be addition of Na₂SO₄ to form "insoluble" SrSO₄. If the solid formed is nano-crystallinic, a co-precipitation with Fe³⁺ or Al³⁺ will form a voluminous Al/Fe(OH)₃-gel which incorporates the nano-particles. The gel is the flocculated with poly-acrylate for fast sedimentation.
The concentration of e.g. Sr²⁺ after this treatment will be 0.1-10 mg/L.

$650M seems a nice budget for AREVA ...