Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[rhody]

In the https://www.physicsforums.com/showpost.php?p=3197547&postcount=539" above, first picture, from left to right, (edited 1:06pm) first long rectangular building, see the whole described by TCups in the previous post ? TCups said he thought he saw something large and heavy fall from the video which had the big vertical plume. In his post he said to the left of the tower, I am wondering out loud if that could be remnants of the "plug" he spoke of ? Because the image is rotated 180% and is now right oriented it fits perfectly with what he claims to have seen. Could the plug or remnants of it be inside the building ? Had we not been given access to the high res photo, this would not be possible, way to go, AntonL. You guys are doing with access to free information what is needed, trying to piece the puzzle together, and I must say doing a fairly amazing job at it. Keep up the good work.


Rhody...

 

[TCups]

Everything I see says the greatest force of the blast at 3 was sideways. Another "bullet" hit in a building in back of unit 3. But most of the girder structure of the roof seems intact. I can't see any good candidates for the "plug". Sure wish we had thermal imaging to study.

 

[Maxion]

Everything I see says the greatest force of the blast at 3 was sideways. Another "bullet" hit in a building in back of unit 3. But most of the girder structure of the roof seems intact. I can't see any good candidates for the "plug". Sure wish we had thermal imaging to study.

That is true, there are quite a lot of IFs in the situation. We don't even know how the reactor in the GE test differs or doesn't from Fukushima 1-3. But the round hole in the turbine building infront of 1-3 is quite interesting in my opinion. I would say the evidence is in favor of the containment buildings cap blowing off, but there are very many if's to be able to say so conclusively.

What do you think, Astronuc? I'd say you would be the best person to guestimate based on the info we have.

 

[Astronuc]

Regarding the plug covering the reactor cavity, I believe the expectation is the hydrogen explosions occurred in the upper or secondary containment, i.e., in the volume of the metal building structure atop the concrete containment. The explosion would then be above the plug.

As far as I know, the emergency plan would be to flood containment with water, which would prevent accumulation of hydrogen, but perhaps there is some voiding (?). Hydrogen rises, so it goes up by the most available pathway. There is a venting system from containment to the tall stacks (towers) that one sees adjacent to each reactor building. It appears that Units 1 & 2 share a stack. Ideally, the atmosphere from containment is filtered and where possible, delayed to allow decay of short half-lived fission gases.

An explosion in containment would be a concern. A strong blast over the spent fuel pool, especially with a reduced pool level would also be of concern with respect to the integrity of the wall, particularly the wall toward the outside of the building.

 

[rhody]

FYI

Not to interrupt the train of thought but here is http://www.iaea.org/newscenter/news/tsunamiupdate01.html" as of March 19, 2011.
I haven't read it fully and digested it yet, it may or may not shed some light on this discussion.
I have included a screen grab of a damage assessment table in the link. Another piece of the puzzle, have at it guys...

Rhody...

edit: P.S. AntonL made a similar post in https://www.physicsforums.com/showpost.php?p=3196974&postcount=521" above, it is the same data, with a greater level of detail than the official IAEA chart in thumbnail above, compare if you wish...

 

[warren_c]

Video of a fire truck spraying water on no. 3:

 

[AntonL]

But the round hole in the turbine building infront of 1-3 is quite interesting in my opinion.

I do not think it is a round hole, video taken on a cloudy day and we would not see into the generator hall as it would be too dark. I think that black is some steel cladding with a roof beam lying on top, similar roof beams from unit 3 can be seen scattered.

 

[TCups]

I do not think it is a round hole, video taken on a cloudy day and we would not see into the generator hall as it would be too dark. I think that black is some steel cladding with a roof beam lying on top, similar roof beams from unit 3 can be seen scattered.

Look again. Clearly, 4 large pieces of debris blasted outward from the wall of Unit 3. Two of 4 chunks traversed the roof of the turbine bldg, damaging the far wall of the turbine bldg. Two more hit the near wall of the turbine bldg, then made it part of the way, then fell through the roof. These were likely the concrete panels between the structural columns of Unit 3.

http://i306.photobucket.com/albums/nn270/tcups/Picture1-3.png

 

[AntonL]

Look again. Clearly, 4 large pieces of debris blasted outward from the wall of Unit 3. Two of 4 chunks traversed the roof of the turbine bldg, damaging the far wall of the turbine bldg. Two more hit the near wall of the turbine bldg, then made it part of the way, then fell through the roof. These were likely the concrete panels between the structural columns of Unit 3.

Yes I can see the 'shaving' marks left by horizontal moving bodies, but these do not cause holes, for holes we need a vertical impact. Also note the black area is the end of the skid mark, so we looking at the body that marked the roof, other two skid marks damaged the east side fascia and whatever caused the marking then fell to the ground.

I still firmly believe the roof of the generator hall has not been penetrated and is intact other than the skid marks and fascia damage.

 

[romillyh]

Video of a fire truck spraying water on no. 3:

And, in case it's any help, story of same with diagram of unmanned truck and seawater pump unit in The Japan Times:

http://search.japantimes.co.jp/cgi-bin/nn20110320a1.html

Aimed at cooling spent MOX in no. 3 pool. We live in hope. (Apols if someone has already posted link -- I checked but can't see it)

 

[Reno Deano]

TEPCO's latest update. I am assuming they mean that no water has leaked from the RPV to the Primary containment, which is questionable.

Press Releases

Press Release (Mar 19,2011)
Plant Status of Fukushima Daini Nuclear Power Station (as of 0:00 pm March 19th)


No New Developments since 9:00pm, 19th March

Unit Status
1 • Reactor cold shutdown, stable water level, offsite power is
available.
• No cooling water is leaked to the reactor containment vessel.
• Maintain average water temperature at 100°C in the pressure
restraint.
2 • Reactor cold shutdown, stable water level, offsite power is
available.
• No cooling water is leaked to the reactor containment vessel.
• Maintain average water temperature at 100°C in the pressure
restraint.
3 • Reactor cold shutdown, stable water level, offsite power is
available.
• No cooling water is leaked to the reactor containment vessel.
• Maintain average water temperature at 100°C in the pressure
restraint.
4 • Reactor cold shutdown, stable water level, offsite power is
available.
• No cooling water is leaked to the reactor containment vessel.
• Maintain average water temperature at 100°C in the pressure
restraint.
other• In the Unit 1, 2, 3 and 4, which automatically shut down due
to the Tohoku-Chihou-Taiheiyo-Oki Earthquake on March 11th, 2011,
we had been preparing measures for decreasing the pressure of each
reactor containment vessel since March 12th. However, on March
17th, we released such preparation in all of the Units.

 

[turbo]

Our military has some very capable autonomous/remote controlled rotor-wing aircraft with visual/IR imaging systems, like the RQ-8A Fire Scout. It is hard to believe that such drones have not been tasked with getting better images than the ones that the public can access. I can understand the military not wanting to disclose the capabilities of their surveillance systems, but this is a pretty dicey situation and more accurate imaging (and not just top-down shots) could be very valuable in assessing damage and charting out a course of action for each damaged reactor.

 

[LanceV]

I wish anyone would publish SOME radiation readings ...

The GRS has been compiling the some of the known radiation data in some nice diagrams (in german but should be self-explanatory):
http://www.grs.de/informationen-zur-lage-den-japanischen-kernkraftwerken-fukushima-onagawa-und-tokai
Especially
http://www.grs.de/sites/default/files/Radiation-Data_Daiichi_20110319-1800.pdf and
http://www.grs.de/sites/default/files/ODL-Werte-Poll_20110319_1715_0.pdf
are interesting.

 

[M. Bachmeier]

Japan reluctant to disclose footage of power plant taken by U.S. drone


http://mdn.mainichi.jp/mdnnews/news/20110319p2a00m0na005000c.html

 

[Angry Citizen]

Note: This is regarding the second link.

It is by no means 'self-explanatory' -- I had to utilize translation software. It is saying that radiation levels less than half a kilometer away from all six reactors has peaked at about five millisieverts/hour for the past several days. This seems to be good news. The purple spikes correlate to the explosions, with the largest one also correlated with the fire at unit 4. I want to know why the main building (Hauptgebäude) is continually reading what appear to be spikes -- large increases followed by exponential decrease.

 

[MadRocketSci2]

My understanding is that when they perform steam venting operations, there is a brief spike in the observed radiation.

 

[83729780]

TEPCO's latest update. I am assuming they mean that no water has leaked from the RPV to the Primary containment, which is questionable.

Press Releases

Press Release (Mar 19,2011)
Plant Status of Fukushima Daini Nuclear Power Station (as of 0:00 pm March 19th)

not Daiichi

 

[edmundredmark]

Lurker de-cloaking here partly to say thanks to the knowledgeable participants and excellent photo researchers in this thread and partly to make a few random comments:

A) On useful vs. stupid coverage of this event: I've been using mainly the New York Times and Kyodo News for news, and I think they've been, not perfect, but pretty thorough and accurate. (For instance, somebody asked a few pages back 'where are our Predator drones'? Well, that was answered by the NYT a day or two ago: there is indeed one in use, and other military surveillance assets normally targeted at North Korea are also being used over the Fukushima site.) With the Times, you have to keep checking back, however -- they do this kind of running update to their main article, rather than publishing a new story every time something new happens.

I've also found the information from the Union of Concerned Scientists and the MIT Dept. of Nuclear Engineering to be valuable.

B) Seems clear that the central issue here at Fukushima is the extended "station blackout". As a layman who went to college (and only a state college, to boot!) and has some decent reasoning capabilities, I'm more than a little aghast that, apparently, in all the emergency contingency planning for NPPs it is simply assumed that a station blackout could never last more than 4-8 hours. I don't think NPPs should be forced to plan for events as unlikely as, say, an attack by Martians, but an event that could knock out grid power and your only set of emergency generators for more than 4 (or, at best, 8) hours? C'mon guys. I think that's grossly irresponsible safety planning, and though I'm not anti-nuclear at all, I am very strongly anti-stupidnuclear.

I look at San Onofre and Diablo Canyon in earthquake-prone California and think they've got to do some serious, and quick, thinking about how to increase redundancy and survivability in their power supplies. Just simply putting some additional diesel generators in a hurricane/tornado/earthquake hardened building a few hundred feet up the hill to a nice elevation, and running some electrical cable underground to the reactor buildings would seem like a simple, and prudent, step that could be taken pretty much now. If I lived in California I would push my elected officials to mandate it now (and be willing to pay a special sales tax or something to pay for it). But I majored in English, so what do I know.

C) One thing on media coverage that I think would be useful is the information that one of the health risks being talked about most here, which is thyroid cancer induced by accumulation of Iodine-131 in the thyroid gland, is actually not that serious a public health threat, relatively speaking. So-called Differentiated Thyroid Cancer (the kind produced by radiation damage) is almost 100% curable in any modern medical system. It ain't fun, but it's not a medical catastrophe in nearly all cases. (I've had it, so speak from personal experience.)

Diablo Canyon NPP:

San Onofre NPP:

[PLAIN]http://images.ocregister.com/newsimages/undefined/2008/07/30_sanonofre1_large.jpg

 

[minerva]

This is interesting.

http://abclocal.go.com/kgo/video?id=8021906

A Zircaloy fuel cladding tube gets introduced to an oxyacetylene torch. It does not actually appear to melt or burn at that temperature.

Are any of you with better nuclear engineering expertise than me able to comment on that? Is it a myth that the Zircaloy actually "catches fire" if heated in air?

There is a lot of very good radiological data coming out of the KEK experimental physics centre in Tsukuba, outside Tokyo.

http://rcwww.kek.jp/norm/index-e.html

Above is their real-time gamma dose monitor.

They also have some very high resolution gamma spectroscopy data, showing the levels of several different significant fission products.

http://www.kek.jp/quake/radmonitor/GeMonitor2-e.html

These fission products are definitely from Fukushima, and they are there at detectable levels – but these instruments are incredibly sensitive, and these levels are absolutely harmless.

We can see the short-lived ¹³²Te dropping away readily over time, as it decays, which makes perfect sense.

We’re talking about, for example, 2 nBq (yes, nanobecquerels) of ¹³⁷Cs per cm³ of air at the moment.

Over the last week I've written a few blog posts about the Fukushima NPP incident as this has been developing. I'm sure some of you might find these posts useful or informative or interesting.

http://reindeerflotilla.wordpress.com/2011/03/19/fukushima-updates-march-18/

http://reindeerflotilla.wordpress.com/2011/03/13/all-right-its-time-to-stop-the-fukushima-hysteria/

http://reindeerflotilla.wordpress.com/2011/03/16/fukushima-redux/

I would certainly love to hear some comments, or peer-review from the more qualified nuclear engineers out there in the audience.

Would anyone care to peer-review my physics on the water loss rate in the used-fuel pool?

I'm still wondering, to be honest, why the LPCIs aren't working at Fukushima I. We know that HPCI can only run for a limited amount of time after SCRAM because there's only a limited amount of heat and steam pressure available in the nuclear steam supply system. RCIC runs on batteries during a station blackout, and those batteries only last for a finite amount of time.

But as far as I understand it, LPCI is designed to run on its own diesel-driven pumps, for days, even without station power, until the heat in the core dropped to the point where cold shutdown is reached.

Can someone explain to me why every single layer of the ECCS seems to have failed at these reactors?

 

[Astronuc]

Regarding the spent fuel pool, see -

Question about spent fuel rod cooling pools in Japàn reactor
https://www.physicsforums.com/showthread.php?t=481599

https://www.physicsforums.com/showpost.php?p=3197363&postcount=12


Zr fires are a concern at the Zr-alloy manufacturing plant - but primarily due to the fines or fine wires that could catch fire. The concern in the pool would be rapid oxidation and the deterioration of the cladding, although some raise the concern of a Zr fire. If the protective oxide cracks, it may be possible to achieve oxidation. Zr + O2 => ZrO2 is exothermic.

The questions for a SFP fire are:

1. Under what conditions does Zr or Zr alloys 'burn'?

2. Are such conditions realized with exposed Zr alloy cladding in a dry or emptied SFP?

Elsewhere I've commented about the manufacturing of Zr alloys in which hot ingots are hot worked to logs for the production of billets.

 

[LanceV]

@minerva:
Thanks for the hint at the KEK data.

You write in your blog:

This is not an injection of seawater into any part of the nuclear reactor or the Nuclear Steam Supply System itself. It is an injection of seawater into the containment structure surrounding the reactor pressure vessel.

Are you sure of this?
In the TEPCO press releases they explicitly say:
"We have been injecting sea water into the reactor pressure vessel."
http://www.tepco.co.jp/en/press/corp-com/release/11031905-e.html
Also the JAIF assumes that sea water is injected into the containment as well as into the pressure vessel in Reactor 1 and 3 and only into the RPV in reactor 2:
http://www.jaif.or.jp/english/

Maybe something is lost in translation, but the rising and falling water levels in the RPV also seem to indicate that water is injected somewhere.
At first I was a bit surpised as well, since there seems to be a danger of a steam explosion if you resubmerge bare fuel rods into the water again, but maybe it is possible.

 

[jinxdone]

Have you taken a look at http://www.youtube.com/watch?v=CmI2lXiTo-g" yet? Rather dubious taking note of the name of the poster and his other videos.. But anyhow, maybe it has some detail to it otherwise missed.

 

[Reno Deano]

From a radiological engineering perspective, it will be nice to see if the TMI upgrades in reactor accident coolant sampling (automated and shielded microliter sampling). At TMI when they tried to do normal coolant sampling 3/8' piping the radiation levels spiked in the sampling room due to fission particle and gases being introduced. The Rad Techs High Range GM Teletectors pegged (>1,000 R/hr). The Techs we shaken mentally at such high radiation levels.

 

[TCups]

Have you taken a look at http://www.youtube.com/watch?v=CmI2lXiTo-g" yet? Rather dubious taking note of the name of the poster and his other videos.. But anyhow, maybe it has some detail to it otherwise missed.

I have now . . . Here are some enhanced stills from the video.

The top of the reactor vessel spewing steam. Note the round hole blasted through the superstructure of the building roof. I believe that to be the equipment pool in the upper left of the photo.

This is what steel reinforcement rods (rebar) left behind after an outward blast with the concrete blown away. They are bent and bow outward.

On the other hand, this is what I think a smashed fuel rod assembly within the rubble after the blast might look very much like. Comments?

I don't know what the yellow stuff is. If it is insulation, and it may be, then there isn't very much of it anywhere else in any of the frames, which makes that interpretation somewhat worrisome. Anyway -- yellow stuff. . .

 

[Thermalne]

On the other hand, this is what I think a smashed fuel rod assembly within the rubble after the blast might look very much like. Comments?

That looks more like a damaged crane structure to me.

I don't know what the yellow stuff is. If it is insulation, and it may be, then there isn't very much of it anywhere else in any of the frames, which makes that interpretation somewhat worrisome. Anyway -- yellow stuff. . .

Looks like piping insulation.

 

[Angry Citizen]

For all y'all know, they're teddy bears. These are grainy photographs of an obliterated structure. Trying to analyze it is futile in my opinion.

One thing we do know is that no corium could possibly be visible in any photograph. The radiation readings would be orders of magnitude higher.

 

[DR13]

CNN has two opinion articles on oppsite sides of the issue:

Anti-Nuclear:
http://www.cnn.com/2011/OPINION/03/19/cooke.nuclear.history/index.html?hpt=C2

Pro-Nuclear:
http://www.cnn.com/2011/OPINION/03/19/chesser.nuclear.future/index.html

The main problem I have with the anti-nuke article is that is references problems from the 50s and 60s and makes no mention of the fact that nuclear safety has progressed. The author keeps saying that it is obvious that eventually something really really bad will happen.

The pro article brings up a lot of points that most people don't consider. For instance, if there is a catastrophic problem at a nuclear plant then bad things happen. Ironically, when fossil fuels are used correctly then bad things happen (climate change, war for oil, etc).

 

[TCups]

That looks more like a damaged crane structure to me.

Which part of this looks like that?

Looks like piping insulation.

Yes, it does. But I am looking hard for any more of it. And it initially looked like the yellow insulation was hanging out the side of the building, not out of the side of the broken pipe. Lots of other broken pipes around without exposed yellow insulation. Look at the transected end of the pipe on the right. The thick wall of the steam pipe (probably 40 years old) looks to be asbestos-insulated.

As I said, though, I don't know what it is.

. . . and it is a nuclear engineering opinion that would be most valuable now, not an anti-nuc or pro-nuc opinion (but I haven't read the pieces, yet. BTW, in disclosure, I count myself in the pro-nuc category).

 

[Reno Deano]

NRC release FAQs regarding the Japanese reactor accidents and how they apply to US reactor sites.

http://www.nrc.gov/japan/faqs-related-to-japan.pdf"

 

[TCups]

For all y'all know, they're teddy bears. These are grainy photographs of an obliterated structure. Trying to analyze it is futile in my opinion.

Then close your eyes. I intend to keep mine open and keep looking. There is always information to be had in photos like these. If not, then someone sure took some outrageous risks on a futile mission. Let's hope the good guys have better quality copies of the images.

One thing we do know is that no corium could possibly be visible in any photograph. The radiation readings would be orders of magnitude higher.

I keep hearing that, but that presupposes that a) someone knew "corium" was likely to be there before they took the pictures, and b) that is is not possible someone would risk their life to get confirmatory pictures. Where nuclear disasters are concerned, we know both of those assumptions are historically inaccurate. And for the record, I never said it was corium.

PS, Angry, just FYI:

This is a teddy bear:
http://images.free-extras.com/pics/t/teddy_bear-539.jpg

and this is a smoldering reactor building:

and that, I am sure of.

The large, round area (circle), is, in my opinion, the top of the reactor. There may be some railing left intact around it. It looks more like a hole with steam coming out of it than an intact plug, but I can't tell. There are no intact roof girders over it. It seems plausible that the plug may have been blown, though. The square would appear to be the equipment pool at the side of the reactor. i wasn't able to identify what I thought was the SFP with certainty.