Japan Earthquake: Nuclear Plants at Fukushima Daiichi

In summary: RCIC consists of a series of pumps, valves, and manifolds that allow coolant to be circulated around the reactor pressure vessel in the event of a loss of the main feedwater supply.In summary, the earthquake and tsunami may have caused a loss of coolant at the Fukushima Daiichi NPP, which could lead to a meltdown. The system for cooling the reactor core is designed to kick in in the event of a loss of feedwater, and fortunately this appears not to have happened yet.
  • #6,091
StrangeBeauty said:
NancyNancy said:
...TEPCO employees were telling a couple of different Japanese reporters I have spoken to that the stability of #4 was a big concern...
link please? The collapse of the building would be a very bad development...
These concerns were made public by Tepco in their "plan". The stability of the #4 SFP was listed as a priority problem. They want to do something about within 3 months.

I read something about reinforcing the construction with steel pillars.
 
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  • #6,092
It's morning (a rare fog-less one). The live cam shows no fire or smoke.
On other nights, I have seen similar... uhh... transients, I guess you might call them.
It's just steam (water vapor), they seem to be doing some/most of their pumping with the Putzmeister at night, plus it tends to be colder so more condensation is to be expected.
I'm beginning to get annoyed with all the fringe theories (even my own).

Sorry for starting up the "omg #4 is crooked" thing, guys :/. Need to do more lurking.
 
  • #6,093
elektrownik said:
Interesting unit 3 have big temperature and cooling problems, they are injecting 9m^3/h but last data show that after litle drop temperature was increasing again
In my opinion, there would be intermittent criticality, in at least one of the reactors but possibly in all 3.
It is known that bottom of reactor 3's PV is at 150 Celsius. That implies fuel laying on the bottom of PV in a lump. It is unclear what happens to control rods but one thing for certain - the fuel won't be laying evenly between control rods, and it won't be mixed evenly with damaged control rod's material (which has dramatically smaller density than uranium dioxide).

It is known that they have been urged to use borated water (by French and by NRC, French even gave them the boron), so the re-criticality is a concern. This concern is not something that goes away with time.

The cooling water is leaking, which means that they are losing boron, and eventually they will run out of boron, at which point cooling could become impossible as non borated cooling water would cause criticality.
The boron in question is not ordinary boron, but enriched boron-10 which is not readily available.
 
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  • #6,095
PietKuip said:
These concerns were made public by Tepco in their "plan". The stability of the #4 SFP was listed as a priority problem. They want to do something about within 3 months.

I read something about reinforcing the construction with steel pillars.
Ah thanks -- I see this from the Roadmap doc:
(Unit 4) Installation of supporting structure under the bottom of the pool.
which is different from the entire building being at risk (not believing that at this point, just asking the question based on the photos we have atm). Sounds like Nancy was referring to something else (a convo between reporters and tepco officials).
 
  • #6,096
StrangeBeauty said:
which is different from the entire building being at risk (not believing that at this point, just asking the question based on the photos we have atm).
Who gives a bleep about the 'entire building' being omfg at risk? The SFP is the only thing that matters. if SFP floor falls out, this can make a level 8 on the scale from 0 to 7 where 7 is Chernobyl.
 
  • #6,097
zapperzero said:
It's morning (a rare fog-less one). The live cam shows no fire or smoke.
On other nights, I have seen similar... uhh... transients, I guess you might call them.
It's just steam (water vapor), they seem to be doing some/most of their pumping with the Putzmeister at night, plus it tends to be colder so more condensation is to be expected.
I'm beginning to get annoyed with all the fringe theories (even my own).

Sorry for starting up the "omg #4 is crooked" thing, guys :/. Need to do more lurking.

So why would they do the Putzmeister pumping at night. Someone tweeted the suggestion it was so people didn't see and become concerned at the sight, but really? That sounds a bit too conspiracy-like even for TEPCO.
 
  • #6,098
biffvernon said:
So why would they do the Putzmeister pumping at night. Someone tweeted the suggestion it was so people didn't see and become concerned at the sight, but really? That sounds a bit too conspiracy-like even for TEPCO.

Temperature conditions at night make it easier for the steam to rise and escape ?

(which is actually strange as temperature inversions occur more often at nighttime :

http://apmru.usda.gov/aerial/Publications/2008 Pubs/Fritz Low level Inversions 2008.pdf

It would however create more atmospheric stability , so better results from spraying

)
 
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  • #6,099
Dmytry said:
Who gives a bleep about the 'entire building' being omfg at risk? The SFP is the only thing that matters. if SFP floor falls out, this can make a level 8 on the scale from 0 to 7 where 7 is Chernobyl.
Of course the SPF is all that matters at #4 although the RPV is probably fairly radioactive itself. But don't you think the entire building collapsing would at least cause the SPF to spill much of its contents? Hopefully the way the building is engineered it's a very unlikely scenario.
 
  • #6,100
GJBRKS said:
(which is actually strange as temperature inversions occur more often at nighttime

Hmm. Inversion layers are good, sort of, because anything caught beneath them doesn't travel far. The zone around the plant is already contaminated, no?
 
  • #6,101
dh87 said:
CO2 is toxic, even at pretty low levels (2%), not that anyone should be breathing the atmosphere, and CO2 will acidify the water.

Mightn't radiolysis also become a concern, separating CO2 into carbon soot and oxygen gas?
 
  • #6,102
rowmag said:
Mightn't radiolysis also become a concern, separating CO2 into carbon soot and oxygen gas?

Carbon monoxide and oxygen gas.
 
  • #6,103
[PLAIN]http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/povray/blueprint/foto/misc/FukushimaSpentFuelRodPoolUnit3-1.jpg

I found this photo somewhere several weeks ago. Google found it again at

http://www.japannewstoday.com/wp-content/uploads/2011/04/FukushimaSpentFuelRodPoolUnit3-1.jpg

By the title, it would seem to be a close-up of the edge of #3's spent-fuel pool, obviously after the explosion, presumably taken by a camera attached to the pump crane. What are those two gray bars at the top left? (They are too smooth and the wrong color to be rebars, and their ends are closed so they do not seem to be conduits.)
 
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  • #6,104
Jorge Stolfi said:
What are those two gray bars at the top left? (They are too smooth and the wrong color to be rebars, and their ends are closed so they do not seem to be conduits.)[/QUOTE]

Looks like a bit of guardrail or something like that. That gray just screams '"anti-corrosion coating" and it fits nicely with the traces of rust.
 
  • #6,105
StrangeBeauty said:
Of course the SPF is all that matters at #4 although the RPV is probably fairly radioactive itself. But don't you think the entire building collapsing would at least cause the SPF to spill much of its contents? Hopefully the way the building is engineered it's a very unlikely scenario.
Well, don't forget that when the building was engineered, the earthquake of such magnitude was considered unlikely to the point of impossibility*, and so was the explosion. I'd say with 4 out of 4 reactor buildings doing things that previously were considered impossible (the hydrogen explosions), all bets are off.
Clearly those things are not quite an example of stellar engineering.
* the quake was much stronger than what buildings were rated for.
 
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  • #6,106
If the primary containment of Unit 3 is cracked, then the SFP is likely also cracked. Damage in the upper primary containment at or near the fuel txfr chute perhaps extending into the level below the service floor seems a possibility. Thermal images are connsistent, IMO
 
  • #6,107
biffvernon said:
So why would they do the Putzmeister pumping at night. Someone tweeted the suggestion it was so people didn't see and become concerned at the sight, but really? That sounds a bit too conspiracy-like even for TEPCO.

They mention the times of spraying to pool 4 in their reports. They often do it in the afternoon or evening, sometimes this extends into the hours of darkness, but it normally starts hours before it gets dark. When they switched rom 58m to 62m concrete pump on 13th April they pumped from 0:30 to 06:57 but I think that's the only time I've seen reports of them starting that late.

For example this report mentions a unit 4 water spraying event that happened a few days back:

http://www.nisa.meti.go.jp/english/files/en20110507-1-1.pdf
 
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  • #6,108
MadderDoc said:
Here is another stab of it (a higher resolution image is attached):
20110324_down_3thumb.jpg

1) Approximate location of apparent kink in the northern boom of the overhead crane (as if it is bent or broken)
2) Approximate location of fire with grey/black smoke on March 21st-22th. Soot on roof girders and wall concrete structure. At floor below, dark shape or possibly crack in service floor.
3) Signature of heat on the winch, and possibly a burn through of the southern boom in this location
4) Missing rails on the top of this section of the southern boom.
5) Areas in which the booms have sunk into the concrete deck of the service floor, extending the NW broken region of the floor.
what is quite interesting, is that the melted-looking hole in the roof grid, severely bent/twisted / heat-damaged looking beams, etc are right over spent fuel pool. It is undeniable that beams next to spent fuel pool have some very specific look not replicated anywhere else.
Maybe Gundersen is right after all.

edit: also, the fire in

happens on the right. (I say fire, not explosion, because I worked in special effects industry. The explosions you see in movies are merely big fires, made by exploding a quite small charge in a condom or a plastic bag filled with fuel. Real chemical explosions of pre-mixed chemicals typically result in gasses that are relatively cold after adiabatic expansion and thus do not make very good mushroom cloud, but can make a strong shockwave and lot of dangerous shrapnel, which is a big no no when filming a movie).
 
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  • #6,109
Am I seeing what I think I'm seeing?

From the U-Tube real time camera it looks to me as if most of the debris from the upper floors of #3 are gone.

Then there are these stills from last night (unless they are a photoshopped prank.)
http://twitpic.com/4unrpd


But not a peep out of anybody.
 
  • #6,110
Unlurk, I was watching about the time those stills were taken. it was odd because I'm used to the puffs of steam coming out regulary, but there was nothing. Then very suddenly 3 and 4 both got very busy. At first I thought it was fog because it can be pretty random, but then it cleared up enough to tell it was 3 and 4. I figured they had started giving them water again.
 
  • #6,112
yakiniku said:
5月1日の政府・東電統合本部全体会合の議事録。
『このままいくと8日にも高濃度の放出が行われる。』
『細野補佐官から,本件は熱交換機の設置といった次のステップに進む上で非常に重要である,また,(今後,放射性物質が外に排出され得るという点で,)汚染水排出の際の失敗を繰り返さないよう,関係者は情報共有を密に行い,高い感度を持って取り組んで欲しい,とする発言があった。』"

Translation (non-literal and our understanding):

I received 3 emails with attachments from junior government officials in the energy department.

The first email:
Minutes of meeting between TEPCO and the government on the 1st May.
"If the current situation continues, high density radiation will be released on the 8th May."
"Mr Hosono said: It is very important to go to the next step regarding the installation of the heat exchanger machine. For the concerned parties, be careful of the sharing of information with high sensitivity so that the same mistakes aren't made again like the release of the radiated water previously.

...Checks date - Checks webcam...

8Jmgb.jpg
 
  • #6,113
Dmytry said:
Well, don't forget that when the building was engineered, the earthquake of such magnitude was considered unlikely to the point of impossibility*, and so was the explosion. I'd say with 4 out of 4 reactor buildings doing things that previously were considered impossible (the hydrogen explosions), all bets are off.
Clearly those things are not quite an example of stellar engineering.
* the quake was much stronger than what buildings were rated for.
I think we're in agreement here... I still don't believe there is an eminent danger of #4 as a whole collapsing, but would like to see evidence countering the apparent (new) lean portrayed by the live camera viewpoint. I've done some looking but haven't found as of yet. Anyone know of a daily satellite feed or aerial imagery? Barrel distortion is more often associated with wide angle lenses, not telephoto.

btw, looks like there's a new url for the live stream:

atm not seeing anything from #3 and #4, and only a bit of white smoke from #2. Lots of atmospheric distortion from daytime heating (wavering images)...
 
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  • #6,114
Bodge said:
...Checks date - Checks webcam...

8Jmgb.jpg

Interesting... I don't think there is a fire or anything like that. Could it be concrete dust stirred up by some part of the building collapsing, e.g. the remaining pillars on the sea-side? Or, if that's right after they started pumping water, maybe some kind of steam explosion?

EDIT: As for the mystery May 8th radiation release (supposedly opening of unit 1 airlock), I don't think these unit 3 events have anything to do with that.

EDIT2: TPS camera during daylight shows unit3 pillars on the sea-side are still standing.
 
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  • #6,115
yakiniku said:
Translation (non-literal and our understanding):

I received 3 emails with attachments from junior government officials in the energy department.

The first email:
Minutes of meeting between TEPCO and the government on the 1st May.
"If the current situation continues, high density radiation will be released on the 8th May."
"Mr Hosono said: It is very important to go to the next step regarding the installation of the heat exchanger machine. For the concerned parties, be careful of the sharing of information with high sensitivity so that the same mistakes aren't made again like the release of the radiated water previously.

What mistakes is he referring to? The release of the radiated water, or sharing of the information regarding it?

The wording of the translation is ambiguous, but my cynical side says this email looks like a caution to the concerned parties to keep their mouths shut.
 
  • #6,116
Borek said:
At STP it is wrong, for reasons so obvious I feel ashamed pointing that out.

Call it nitpicking if you like :biggrin:

:redface: Uhh, yes at STP you are right that H2O usually prefers not to be in gas form.

But for my defense, I did not specify the temperature and pressure, but I wrote "H2O gas" ... :tongue2:
 
  • #6,117
MiceAndMen said:
What mistakes is he referring to? The release of the radiated water, or sharing of the information regarding it?

The wording of the translation is ambiguous, but my cynical side says this email looks like a caution to the concerned parties to keep their mouths shut.

I read the original as saying the opposite: keep "related parties" closely informed, and treat this matter with the great sensitivity, so as to avoid a repeat of the mistakes they made with the water-release.

Recall the water-release problem: they announced publically that they were dumping low-level contaminated water just before they had to do it, and got lots of complaints from fishing groups, neighboring countries, etc. They are saying to keep everybody who might be affected in the loop this time.
 
  • #6,118
NancyNancy said:
It was suggested that I share this here. A couple of people had mentioned #4 looked like it was falling over or it is an optical illusion of the wide angle lens on the TBS camera. I am not totally convinced it is the camera since there is no oddity on the opposite side of the camera. I also have a screen shot that shows even further right of #4, everything is totally vertical. #3 isn't leaning, as if there was a distortion, it would gradually get worse rather than being sudden in one spot only.

Imho unit 4 is not leaning. An easy way to check would be to look if there is any difference in how unit4 appears compared to earlier footage of that TBS camera. Also there seems to be a lot of atmospheric distortion in those images. My personal impression is that unit 3 also appears slighlty tilted in those images sometimes. As for the one spot only, maybe there is some dirt on the their camera lens...

Assuming for a moment it really is leaning slightly, that could also be related to some discussion further up that the ground there might have moved during the earthquake, and the whole complex seems to have moved down from the point of view of the TEPCO webcam.
 
  • #6,119
rowmag said:
I read the original as saying the opposite: keep "related parties" closely informed, and treat this matter with the great sensitivity, so as to avoid a repeat of the mistakes they made with the water-release.

Recall the water-release problem: they announced publically that they were dumping low-level contaminated water just before they had to do it, and got lots of complaints from fishing groups, neighboring countries, etc. They are saying to keep everybody who might be affected in the loop this time.

Yes. If I may, I would like to give you an unpolished translation (one that retains much of the grammar of the original) to give people who do not know Japanese a better idea (of course, we have to change the order of the parts of the sentence or the statement will be garbled to an English speaker):

"Also, (from now on, this is the issue of radiactive material being released to the outside,) I would like authorized people to share information densely/ closely/ tightly/ minutely, in a manner that does not repeat the mistake(s) on the occasion of emitting/ releasing contaminated water, to tackle/ deal with (the) high sensitivity."

[STRIKE]Given that he uttered this in public, and[/STRIKE] given the many (even international) problems that the release of contaminated water have caused, he surely means that he would like those responsible to not repeat the error of the past, which was a lack of information, and to be aware of the sensitivities of other parties concerned.

(edited myself)
 
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  • #6,120
Dmytry said:
Well, don't forget that when the building was engineered, the earthquake of such magnitude was considered unlikely to the point of impossibility*, and so was the explosion. I'd say with 4 out of 4 reactor buildings doing things that previously were considered impossible (the hydrogen explosions), all bets are off.
Clearly those things are not quite an example of stellar engineering.
* the quake was much stronger than what buildings were rated for.

I don't know about Japan and about the time when the units were built, but at least some (if maybe few) people did consider the effects of a possible hydrogen explosion, see the paper linked to in post #6055.

In general, I would also have expected that NPPs would be engineered a bit safer than that, but they survived the earthquake itself pretty well, as it seems. Too bad they apparently "forgot" about tsunamis...
 
  • #6,121
I have not figured out how to quote in posts here yet. In reference to #4 leaning over. I have more images, will have them online tomorrow morning and will also share them here.

I spoke with a couple of reporters in Japan again. One who has been reliable on lots of other information about the plant and has contacts with the workers and technical staff there told me a couple of things.

1. that is not an illusion on the TBS camera, they asked the technical crew running the camera, has a professional direct contact with them. Technical crew says the building is leaning over, it isn't a distortion of the camera lens.

2. the building is leaning over, confirmed it with workers at the plant. They have a company contracted to try to come in and install the cement pillars but didn't have word if that has started or is still in planning (or if it can still happen).

Sorry I can't provide further evidence on these two points. I am lucky to have reliable sources in the media in Japan and they put themselves at risk talking freely. I won't put anyone in possible trouble so take it as you will. These people have been days ahead and right on everything so far, so I am pretty confident in what I am getting for information..
 
  • #6,122
The live feed went dead while I was watching it. Can anyone see it right now?
 
  • #6,123
robinson said:
The live feed went dead while I was watching it. Can anyone see it right now?
Live feed works ok for me. .
 
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  • #6,124
Thanks. That one is working.
 
  • #6,125
NancyNancy said:
I have not figured out how to quote in posts here yet. In reference to #4 leaning over. I have more images, will have them online tomorrow morning and will also share them here.

I spoke with a couple of reporters in Japan again. One who has been reliable on lots of other information about the plant and has contacts with the workers and technical staff there told me a couple of things.

1. that is not an illusion on the TBS camera, they asked the technical crew running the camera, has a professional direct contact with them. Technical crew says the building is leaning over, it isn't a distortion of the camera lens.

2. the building is leaning over, confirmed it with workers at the plant. They have a company contracted to try to come in and install the cement pillars but didn't have word if that has started or is still in planning (or if it can still happen).

Interesting. Looking forward to those new images.

Is the building leaning towards the sea-side? Because the pillars on the south side look pretty much intact below the service floor. I don't think the inner structure such as the reactor and sfp are resting on the outside pillars (that's at least what I would hope), so that it wouldn't really matter much if the outer hull of the building is leaning, unless it is going to collapse and stuff falls into the sfp. Or is the whole unit supposed to lean from ground up?
 

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