Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[ascot317]

Sarcasm seems uncalled for.
When that decision was made, quite reluctantly and perhaps too late, there was no other way to try to cool the reactors.
We should always remember the site is in the middle of a disaster zone, with 25,000 people dead and many times that number homeless.

I'm referring (see the link I quoted in my post) to the sodium-cooled fast breeder that apparently swallowed a 3.3 tonne loading machine they now can't retrieve. Just a few months after the first restart in >15 years after the last incident there (15 years that included a technical overhaul). They apparently can't let it run for much more than a year without something terrible happening. It's just radioactive sodium and MOx-fuel.

 

[andybwell]

None taken I was simply defending my idea that the core shroud could fit through a hole of that size in response to your picture that suggested it was impossible due to physical size constraints. There are good arguments against that being the actual ingress point for the new core shroud, but, "It won't fit," isn't one of them.


My central contention in all this is that the green box/framework/hole thing could have had something to do with the core shroud replacement project, not that that spot was definitively the location of core shroud ingress. I really don't care how they got them in and out of the building. The core shroud replacement job is much more than a routine refueling outage. There must be (literally) tons of extra equipment and tools needed above and beyond what's normally in the reactor building, and maybe whatever was happening on the low roof in the SE corner of the building was in a support role for all that extra stuff.

The explosions in buildings 1 and 3 have been attributed to a buildup of H2 gas that escaped from primary containments. The etiology of the building 4 explosion must have been very different. Did the green box/framework/hole apparition and/or the core shroud replacement work contribute to the explosion of building 4? I think we're no closer to answering that question than we were on 12 March.

Could the explosion in building 3 have been within the reactor core, and blown its lid off so that it is now exposed to the air?

 

[~kujala~]

Funny, it was indeed the cooling that caused the cooling problems at #1 right after the earthquake but not the isolation condenser being too weak but too powerful. This is the impression one gets when reading The Daily Yomiuri:

The TEPCO operational manual says the reactor's temperature should not be allowed to fall at a rate of 55 C per hour or more, and isolation condenser operations should be adjusted to prevent such an occurrence.

TEPCO said its workers halted the cooling system because it had caused excessive cooling, with the reactor temperature falling more than 100 C in the time the condenser had been operating.

http://www.yomiuri.co.jp/dy/national/T110524005786.htm

 

[etudiant]

I'm referring (see the link I quoted in my post) to the sodium-cooled fast breeder that apparently swallowed a 3.3 tonne loading machine they now can't retrieve. Just a few months after the first restart in >15 years after the last incident there (15 years that included a technical overhaul). They apparently can't let it run for much more than a year without something terrible happening. It's just radioactive sodium and MOx-fuel.

The Monju accident is a stunner, no doubt about it.
Considering that this reactor had a major breakdown before, with sodium leaking and pooling everywhere, it is almost incomprehensible that the operations would again be mismanaged so badly.
Given that the breeder is Japans best hope for energy independence, one would have hoped for better.

 

[SteveElbows]

Results of air sampling from above reactors 1 & 4 is out, not sure I've seen this mentioned here till now?

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110524_01-e.pdf

Numbers too low to cause much excitement? Not that these reactors were looking like the best candidates for giving off the largest releases, and I am not entirely sure about TEPCOs choice of sampling point above each building either. Whats located in the corner of unit one that they chose?

(photos showing sampling locations here http://www.tepco.co.jp/en/news/110311/index-e.html )

 

[Borek]

I see we are back to armchair blaming TEPCO management and engineers. Please move this part of the discussion elsewhere.

Just in case you all forgot:

Do not condemn until you have walked in their shoes.

 

[maddog1964]

I see we are back to armchair blaming TEPCO management and engineers. Please move this part of the discussion elsewhere.

Just in case you all forgot:

Thank you.

 

[andybwell]

Results of air sampling from above reactors 1 & 4 is out, not sure I've seen this mentioned here till now?

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_110524_01-e.pdf

Numbers too low to cause much excitement? Not that these reactors were looking like the best candidates for giving off the largest releases, and I am not entirely sure about TEPCOs choice of sampling point above each building either. Whats located in the corner of unit one that they chose?

(photos showing sampling locations here http://www.tepco.co.jp/en/news/110311/index-e.html )

I am reading info stating almost 200 sieverts per hour at reactor 1. Is this believable?

http://webcache.googleusercontent.com/search?q=cache:qp1hOuKX1zgJ:atmc.jp/plant/rad/+%3Ca%20href=

 

[andybwell]

I am reading info stating almost 200 sieverts per hour at reactor 1. Is this believable?

http://webcache.googleusercontent.com/search?q=cache:qp1hOuKX1zgJ:atmc.jp/plant/rad/+%3Ca%20href=

My apologies, I did not see the "instrument failure" next to graph.

 

[jmz007]

I am reading info stating almost 200 sieverts per hour at reactor 1. Is this believable?

http://webcache.googleusercontent.com/search?q=cache:qp1hOuKX1zgJ:atmc.jp/plant/rad/+%3Ca%20href=

you read it right, but not completely. it says "instrument failure" in the header.

.edit: I'm slow..

 

[elektrownik]

My apologies, I did not see the "instrument failure" next to graph.

I can't agree with this, on tepco data there is no info about sensor damage, and there is more data, look on tepco data not on this site, some days ago it show 5000Sv in unit 4... tepco data is first and best information source...

 

[ottomane]

"instrument failure" is only found in these documents (what source is this?), not in the original tepco datasets.

 

[Atomfritz]

some days ago it show 5000Sv in unit 4... tepco data is first and best information source...

aaaawww... 5000 Sv? where exactly? link pls :)

 

[MiceAndMen]

Could the explosion in building 3 have been within the reactor core, and blown its lid off so that it is now exposed to the air?

Not likely.

 

[Uagrepus]

The original photo with "fried pixels" near Unit 2 is in Tepco's press releases:

http://www.tepco.co.jp/en/news/110311/images/110412_1f_tsunami_6.jpg

The Exif-info of this picture shows the used camera was a Sony DSC-P32. Some people mod this model by replacing the infrared filter glass with normal glass in front of the CCD-sensor:
here ...
http://www.pixcontroller.com/forums/index.php?act=attach&type=post&id=3528
or ...
http://www.pixcontroller.com/forums/index.php?act=attach&type=post&id=3564

The original picture is from this photo-session ...

http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110409e9.pdf

and the single photos are linked on Tepcos site ...

http://www.tepco.co.jp/en/news/110311/index-e.html
... beginning with date "2011.4.11 (Fukushima DaiIchi Nuclear Power Station)".

Alas none of the other photos that day were shot with this Sony DSC-P32 (Panasonic, Olympus etc.), so there is no reference, whether the Sony cam had these pixel anomalies before or after that take :-/

Wasn't lovely bionerd23 using a Sony CCD in her video?
http://www.youtube.com/all_comments?v=jFNvYA7731o

 

[clancy688]

Some new informations by EX-SKF again.

http://ex-skf.blogspot.com/2011/05/containment-vessels-of-reactors-1-2-3.html

http://ex-skf.blogspot.com/2011/05/multiple-10-centimeter-holes-in-reactor.html

Someone at Yomiuri Shinbun who was made to read the TEPCO's report to the Nuclear and Industrial Safety Agency (NISA), the government overseer, found this bit of information in the main report (225 pages, in Japanese; English translation is on-going at TEPCO): Containment Vessels were damaged within 24 hours of the quake.

According to the Mainichi article, TEPCO came to the conclusion of multiple 10-centimeter holes in the Reactor 2 Containment Vessel and one 7-centimeter hole in the Reactor 1 Containment Vessel from the analysis of the pressure data.

I'm really anticipating the translated version of this 225 page report. But this will take a while. One month according to TEPCO - http://www.tepco.co.jp/en/press/corp-com/release/11052412-e.html

Still, there are two new releases.

Summary of the analysis - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e13.pdf
Status of reactor cores 2 and 3 - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf

Typical TEPCO humor again...

Seeing that cooling by water injection is continued, we don't think it will develop into the serious situation that leads to a large-scale emission of radioactive materials.

To sum it up, we have a INES level 7 radioactivity release, we have 10% of Chernobyl emissions, the whole pacific is now a nuclear waste storage facility and probably half of Fukushima prefecture is an exclusion zone, but that still is not, I quote, a "serious situation" with "large-scale emission of radioactive materials".

 

[andybwell]

"instrument failure" is only found in these documents (what source is this?), not in the original tepco datasets.

It appears to be from a Company called ATMC

http://www.atmc.co.jp/company.html (I translate it using Google Chrome)

 

[jlduh]

Some new informations by EX-SKF again.

http://ex-skf.blogspot.com/2011/05/containment-vessels-of-reactors-1-2-3.html

http://ex-skf.blogspot.com/2011/05/multiple-10-centimeter-holes-in-reactor.htmlI'm really anticipating the translated version of this 225 page report. But this will take a while. One month according to TEPCO - http://www.tepco.co.jp/en/press/corp-com/release/11052412-e.html

Still, there are two new releases.

Summary of the analysis - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e13.pdf
Status of reactor cores 2 and 3 - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf

This article is again very interesting and i second all the comments and remarks.

http://ex-skf.blogspot.com/2011/05/containment-vessels-of-reactors-1-2-3.html

It's been revealed that the steel Containment Vessels of the Reactors 1, 2 and 3 that house the Reactor Pressure Vessels (RPV) may have been damaged within 24 hours after the earthquake on March 11, according to the detailed analysis of the core meltdown at Fukushima I Nuclear Power Plant by TEPCO.

Pfff, they start to become very predictable at Tepco: just read the last sentence of my post moved here

https://www.physicsforums.com/showpost.php?p=3320250&postcount=171

A little bit more time will tell what did damage these vessels, but earthquake is a good candidate.

 

[SteveElbows]

A little bit more time will tell what did damage these vessels, but earthquake is a good candidate.

Im not convinced that it is. If they are basing containment damage estimates on pressure readings, then have to look at the time the pressure readings that are indicative of containment failure occur, and we would expect this to be quite a long time after the earthquake itself from everything I remember of pressure data at all the reactors..

I do not rule out the possibility that the earthquake damaged some stuff, but any signs of this remain elusive, and so much happened within a short space of time. Its fairly hard to separate earthquake damage, tsunami damage, human error and loss of power as factors which influenced events of the first few hours.

At this point I will assume that damage to containment etc was result of conditions inside the reactors once sufficient cooling & water levels were lost, because almost all of the data we have that shows bad stuff happening, either to fuel, reactor vessel or containment, is from later on.

 

[rowmag]

[Posted in other thread, copying here.]

From this morning's paper:

http://www.asahi.com/special/10005/TKY201105240733.html

Summary: Unit 3 ECCS (Emergency Core Cooling System?) may have been damaged by the earthquake, before the tsunami arrived.
(According to analysis released by TEPCO on the 24th.)

Add: I guess the analysis is the report EX-SKF was talking about: http://www.tepco.co.jp/cc/press/betu11_j/images/110524a.pdf
Ooh, this looks juicy. Good bedtime reading.

 

[LabratSR]

"instrument failure" is only found in these documents (what source is this?), not in the original tepco datasets.

Look at the bottom of the second page under the CAMS data.

http://www.tepco.co.jp/en/nu/fukushima-np/f1/images/11052406_level_pr_data_1u-e.pdf


From here.

http://www.tepco.co.jp/en/nu/fukushima-np/index-e.html

 

[SteveElbows]

Using dodgy computer translation of small parts of that large document, I have been able to learn more about the containment damage that appears to factor into their analysis. There is loads more that I am not even going to try to get my head round using computer translation, for now I was content to get some idea of the timing they were considering for this containment damage:Reactor 1:

At the time of analyzing concerning the hypothesis of vapor phase leakage from 1 Containment Vessel, in order it is to adjust to the value of the Containment Vessel pressure which is really measured, the Containment Vessel (the dry well (calling below “D/W”,) you supposed the leakage (approximately φ3 cm) from the vapor phase section from earthquake occurrence in after approximately 18 hours. In addition, enlargement (approximately φ7 cm) of leakage was supposed in after approximately 50 hours. However, to be hypothesis in regard to analysis to the last, whether it is unconformity of measurement value and the analytical value due to the problem of the or meter side which really has leakage from Containment Vessel (D/W), at present time it is unclear.

Reactor 2:

In order it is to adjust to the value of the Containment Vessel pressure which is really measured at the time of analyzing concerning the hypothesis of vapor phase leakage from 2 containment vessels, the Containment Vessel (D/W) leakage from the vapor phase section (approximately φ10 cm) you supposed from earthquake occurrence after approximately 21 hours. In addition, in the same way the pressure control room of 3/15 (calls below “S/C”) the strange noise which occurs in near was supposed in boundary, the Containment Vessel (S/C) leakage from the vapor phase section (approximately φ10 cm). However, to be hypothesis in regard to analysis to the last, whether it is unconformity of measurement value and the analytical value due to the problem of the or meter side which really has leakage from the Containment Vessel, at present time it is unclear.

As for what they say about reactor 3, I cannot rely on the computer translation enough to even begin to describe their position on that.

If the computer translation is even half accurate, it certainly does not sound like their analysis is based on anything more sturdy than the data we already know about, and it may be a crude approximation just to make all the other numbers work in their analysis.

As for what caused these containment failures, I have only translated little bits so far but I would not be surprised if its the same theory as we have heard in the past - things get too hot and/or under too much pressure, and a variety of weak spots are the candidates to break first, whether they be gaskets or whatever. But they may have additional thoughts on this that I cannot understand yet, and as I said I am especially unclear what their analysis of reactor 3 is exactly.

 

[MiceAndMen]

[Posted in other thread, copying here.]

From this morning's paper:

http://www.asahi.com/special/10005/TKY201105240733.html

Summary: Unit 3 ECCS (Emergency Core Cooling System?) may have been damaged by the earthquake, before the tsunami arrived.
(According to analysis released by TEPCO on the 24th.)

Add: I guess the analysis is the report EX-SKF was talking about: http://www.tepco.co.jp/cc/press/betu11_j/images/110524a.pdf
Ooh, this looks juicy. Good bedtime reading.

Beginning on page 215 are diagrams of all 6 Daiichi RPVs that show instrumentation levels. I'll be waiting for the English version of the entire report myself, but the diagrams are pretty clear by themselves for now.

 

[andybwell]

Not likely.

Look at the 5th picture. At the top of the photo you see the skeletal remnants of the wall of the 3rd and 4th floors. There are two massive steam pipes running behind and below the building...the lower edge of the lower pipe is almost perfectly aligned with the floor level of the 3rd floor. Follow the floor line of the third floor down down from that back wall along the right side of the building, then across the front side of the building near the bottom of the photo. There is nothing but air remaining above that level, except for a bit of roof debris which you can see through. Is that the top of the primary containment vessel, as well as the top of the reactor itself?

http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.htm

 

[StrangeBeauty]

Look at the 5th picture. At the top of the photo you see the skeletal remnants of the wall of the 3rd and 4th floors. There are two massive steam pipes running behind and below the building...the lower edge of the lower pipe is almost perfectly aligned with the floor level of the 3rd floor. Follow the floor line of the third floor down down from that back wall along the right side of the building, then across the front side of the building near the bottom of the photo. There is nothing but air remaining above that level, except for a bit of roof debris which you can see through. Is that the top of the primary containment vessel, as well as the top of the reactor itself?

http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.htm

No. The reactor and containment are on the opposite side of the building. If you are truly interested, you need to look back in the thread to see the discussion of the layout of the building (with many excellent pictures), and the ramifications of your highly unlikely scenario.

Extraordinary claims require extraordinary evidence. E.g. show us a clear picture of the primary containment cap or its fragments. (Actually I'd like to see a clear picture of the caps regardless of their location and state)

 

[MiceAndMen]

Hm? What distorsion?

(As someone else pointed out, your reputation is fine. It's the webcam that has a poor one.)

The pictures from that JNN webcam present a distorted view of reality. The original image is an SD (Standard Definition) 4:3 aspect ratio frame that has been stretched out to fill a 16:9 frame and falsely presented as HD.

Here's what it looks like (16:9 faux HD stretch-O-vision):

And here's what it should look like (4:3 SD aspect ratio):

The live feed is a distraction at best and at worst it provides grist for the rumor mill. It has lead to all kinds of absurd speculation including:

• The reactors are belching smoke (at least twice a week someone posts this)
• Building 4 is leaning
• Reactor 3 is on fire

My opinion is that that webcam has produced zero useful observations since Unit 3 exploded. I have never tuned into the live feed; it shows nothing of interest unless you're looking for a weather report. I wish they would just turn the damn thing off, at least until something new and interesting actually happens at the site.

 

[MiceAndMen]

Look at the 5th picture. At the top of the photo you see the skeletal remnants of the wall of the 3rd and 4th floors. There are two massive steam pipes running behind and below the building...the lower edge of the lower pipe is almost perfectly aligned with the floor level of the 3rd floor. Follow the floor line of the third floor down down from that back wall along the right side of the building, then across the front side of the building near the bottom of the photo. There is nothing but air remaining above that level, except for a bit of roof debris which you can see through. Is that the top of the primary containment vessel, as well as the top of the reactor itself?

http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.htm

The topic and all those pictures were discussed here weeks ago. The photos were dissected and analyzed thoroughly. I respectfully suggest that you go back and review that discussion and how the photos were marked up and annotated. If you find a new angle that hasn't been discussed yet I'm sure people will be happy to engage you in conversation about it.

 

[andybwell]

Also for the sake of adding the final bit of info I have left to add to conversations about round equipment and the layout of the reactor fuel service floor, I think the same video also shows the reactor cap of unit 4, has this been noticed before?

Watching the video from around the 2 mins 46 seconds mark to get bearings in relation to the yellow containment cap that we know very well already. Watch as the camera starts to show stuff that is further to the right of this yellow cap. Pause it around 3 mins 6 seconds. There is a bit of circular equipment visible at the top of the image, I believe this is still attached to the reactor cap after removal of the cap, and with that in mind a fairly faint image of a dark cap becomes apparent. They look like they are leaning noticeably, but I am wary of how much things can be misjudged due to angle image is being shot at, etc.

I apologize for not doing due diligence research before posting.

http://www.youtube.com/user/modchannel#p/a/u/0/ZKFGavZ_rf4

 

[andybwell]

The topic and all those pictures were discussed here weeks ago. The photos were dissected and analyzed thoroughly. I respectfully suggest that you go back and review that discussion and how the photos were marked up and annotated. If you find a new angle that hasn't been discussed yet I'm sure people will be happy to engage you in conversation about it.

I was looking at those pictures for the first time today and the hackles went up on the back of my neck as to the enormity of this catastrophe and its ramifications if it cannot be "stabilized"

 

[StrangeBeauty]

I apologize for not doing due diligence research before posting.

http://www.youtube.com/user/modchannel#p/a/u/0/ZKFGavZ_rf4

Oops I wasn't completely clear. I meant for units 1-3. The unit #4 bright yellow cap has been visible in many pics for weeks now.

...and its ramifications if it cannot be "stabilized"

I share your concern. I think the characterization of the situation being 'static' is generally accepted as a description of the recent past. All aspects of the situation are certainly not 'stabilized' and there are many unique problems to conquer in trying to get the site safe, and cleaned up, not to mention trying to get significant swaths of the countryside habitable again. I'm not sure anyone here thinks that it can't eventually be 'stabilized' but how long that takes and the final cost in earth, air, water, money, and humanity is up for speculation.

It is difficult to assess the probability of something new going catastrophically wrong at this point (e.g. SPF4 collapsing; another explosion; etc.).