Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[Demidrol]

I don't think this image has been posted before but seems to show refueling operations at one of the reactors.

And in what is known?

 

[razzz]

We can only speculate but look at aerial-2011-3-30-0-50-45.jpg from 20 March... if those are tsunami runups then we have an idea.

Google Earth shows elevation where ever you point the mouse.

 

[jensjakob]

Here is another crop of the northside of #3.

I am as sure as I can be, that the side was blasted out - and my best shot is that the blast originated from the equipment pool.

 

[83729780]

We have heard many times that the radiation coming from the standing water is > 1000 mSv / hr. So we don't know the actual levels, just that it's greater than the 1000. I believe some here have estimated this value to be wildly lower than the actual.

Lately there have been reports of this water being > 10,000 times the level of water normally in a reactor.

Would I be right therefore in assuming that the normal level of radiation levels of water in a reactor is approx 0.1 mSv / hr?

Basically I was wondering if the "levels > 10,000" was as limited a piece of information as the "> 1000 mSv/hr" one. Or, if we could perhaps work out an actual level of radiation from those figures of "> 10,000 times the normal level in a reactor"

the multiplier references radioactivity (becquerels), not radiation

there's also a need to distinguish "times normal level" from "times legal limit"

also, the >1,000 mSv/hr was a measurement taken a couple of days ago from water in the turbine building of reactor 2. The most recent measurement of "10,000 times the legal limit" was a becquerel measurement from water near reactor 1 (see AntonL's post on the previous page [https://www.physicsforums.com/showpost.php?p=3221570&postcount=2251"])

 

[jensjakob]

I don't think this image has been posted before but seems to show refueling operations at one of the reactors.

Leads to some very interesting questions:
1. The refueling machine has narrower width than reactor opening. (Which is square).
2. Does this mean that fuel only can be stored in the SPF pool, since the refueling machine can't move to the other side of the reactor?
3. Can the "crane" turn around and operate on the other side (e.g. if there were tracks in the reactor concrete lid so the refueling machine could be restationed to the other side?)

Curios
Jens Jakob

 

[jlduh]

Ms Music: I double checked and you are right on one thing: the supposed fuel rods on the roof was a place at No3 reactor, and not No4 as previously stated.

But I think the resolution on the Hi res picture is still not sufficient to see such small sticks. I did a capture that puts precisely right in the middle the place where the supposedly "fuel rods" are seen on the video, it was close to these green spots. The rebar was more on the lower left side of my screenshot.

http://www.netimago.com/image_184819.html

To me it is impossible to decide if they are there or not. But i confirm that this would be a strange place to be for a fuel rod as the SPF is on the other side.

 

[TCups]

I don't think this image has been posted before but seems to show refueling operations at one of the reactors.

Very helpful.

The approximate size and relative location of the refueling chute in the SFP is apparent.

We know that this building has the concrete superstructure, like Bldgs 3, 4.

We know that the yellow dome to the left is the drywell cap.

Does anyone know what is sitting in the corner behind the drywell cap?

 

[jlduh]

Unit 4 did a full core offload for maintenance

Astronuc, can you confirm that it was stopped for full maintenance with all the fuel rods outside of the core?

EDIT: Well i checked the IRSN reports they say the core was unloaded so i guess it was and you are right.

If that's the case (I missed the detail, i just noted that it was shut down for maintenance which i interpreted -probably wrongly- as fuel maintenance) then my post below is irrelevant (still the destructions to Building 4 are impressive if we consider only an H2 explosion from the top floor and the SFP... It's pity we didn't have any video from this or these explosion(s)

https://www.physicsforums.com/showpost.php?p=3221404&postcount=2226

 

[james14]

the multiplier references radioactivity (becquerels), not radiation

there's also a need to distinguish "times normal level" from "times legal limit"

also, the >1,000 mSv/hr was a measurement taken a couple of days ago from water in the turbine building of reactor 2. The most recent measurement of "10,000 times the legal limit" was a becquerel measurement from water near reactor 1 (see AntonL's post on the previous page [https://www.physicsforums.com/showpost.php?p=3221570&postcount=2251"])

Thanks for that, its a distinction that I didn't understand at all.

I assume there is at least some connection? IE an increase in the level of radioactivity (becquerels) would normally result in a higher dose of radiation (sieverts)?

And if so, is it possible to estimate one from another, or is it just not feasable?

Thanks again!

 

[shadowncs]

Google Earth shows elevation where ever you point the mouse.

Yes, that would be the hill behind the plant and if those are runups then the tsunami left the mark on those hills. Look at the left marks that cross a road going downhill at an angle. If they're not runups I don't know what they are.

 

[Illbilly]

Very helpful.

The approximate size and relative location of the refueling chute in the SFP is apparent.

We know that this building has the concrete superstructure, like Bldgs 3, 4.

We know that the yellow dome to the left is the drywell cap.

Does anyone know what is sitting in the corner behind the drywell cap?

Could it be the fuel elevator?

 

[Ms Music]

Sorry, I guess this WAS being debated recently.

It still appears to be there, in the NW corner of Bldg 3

.

You are right that what the helicopter is focusing on in seconds 54 to 58 is still there, but what they appear to focus on during seconds 50 to 53 appears to be gone, but I will just pass it off to poor resolution images.

Fuel rods definitely does not make sense to be in that area.

I just hope they can get things under control soon. I feel terrible for all workers involved, and all the people in the region affected.

 

[PietKuip]

As a former NPP manager, I've been closely following this event from the beginning, but just found this forum yesterday. I've been trying to put myself in their shoes to better understand what they are dealing with.
I would fully expect that they are doing their best to limit doses to workers ALARA - even in these very stressful circumstances. They would not be irresponsibly simply ordering someone to go and get a sample. They would do their best to use long handled sampling, different routes etc and HP briefings to minimize dose.

Now we hear how irresponsible Tepco is: they had not even brought in sufficient numners of personal dosimeters for the people working there. It is disgusting.

 

[jinxdone]

I ran into a video clip from a camera mounted to the boom of a crane used to pump water into the SFP of reactor building 4.

http://www.ustream.tv/recorded/13684184

On the clip the view is mostly obscured either by roof structures or billowing smoke/steam. Here's a few images where the smoke is out of the way.

I assume this was taken from the same red crane that is visible in the recent aerial images.

[URL]http://i.telegraph.co.uk/multimedia/archive/01861/fukushima-aerial_1861606c.jpg[/URL]

*PS Take a look at the video yourself to get a better idea where the smoke or steam is originating from

 

[Borek]

Now we hear how irresponsible Tepco is: they had not even brought in sufficient numners of personal dosimeters for the people working there. It is disgusting.

To quote earlier post from the same thread:

Do not condemn until you have walked in their shoes.

 

[hbjon]

Yes. A steam explosion can occur without air being present:
http://en.wikipedia.org/wiki/Steam_explosion"

And at high enough temperature (>1700 Celsius) zirconium also reacts explosively with steam producing hydrogen without the need for air.
Zr + 2H2O -> ZrO2 + 2H2

Of course once hydrogen escapes the containment it can also explode in air.

Any danger of the H-2 fusing together? Or at the current temp and pressure this not possible?

 

[Astronuc]

Any danger of the H-2 fusing together? Or at the current temp and pressure this not possible?

No. The only concern about hydrogen is deflagration or detonation. Beyond that, the concern is the degraded condition of the fuel, which no longer confines the fission products. Beyond that is the degraded condition of the reactor coolant system which provides the next barrier between fission products and the environment. Beyond that is the degraded condition of the containment system which is the third barrier between fission products and the environment.

Proton fusion has a relatively low probability even in the center of the sun with a density of 160 g/cm³, 10 times that of lead, or 160 times that of water at 1 atm and ~25°C. The sun's core temperature of 15 million K (27 million °F) keeps it in a plasma state.

Ref: http://fusedweb.pppl.gov/cpep/chart_pages/5.plasmas/sunlayers.html
http://hyperphysics.phy-astr.gsu.edu/hbase/astro/solarpp.html
http://csep10.phys.utk.edu/astr162/lect/energy/ppchain.html (On average it takes about 10⁹ years for a proton to fuse with another proton! That's why the sun is around so long.)

Normal condition in the BWR core is a mix of saturated liquid water and steam at ~286°C, with the cladding temperatures a bit hotter, and the fuel temperatures of 350-1400°C, where the highest temperature of the fuel is the centerline. In the current situation, the fuel temperature is much low, probably on the order of 200-400°C.

 

[sigyn]

Any danger of the H-2 fusing together? Or at the current temp and pressure this not possible?

No possibility of fusion.

 

[gmax137]

That looks like a bunch of 3/8 inch stainless tubing to me. There's typically miles of that stuff in a plant, used for instrumentation.

It does not to me.

I see rumpled elongated narrow sheets that were made that way by physical shock, like from that explosion.
They appear to be (approximate guess) ten times to fifteen times wider than they are thick.
For them to have taken on such a rumpled shape their substance must have some malleability, much like lead.
What ever fits that description is what it is.

I think they are fuel rods that have been through one hell of an explosion.


But what the hell, I am not a nuclear engineer. I just go by what my eyes tell me.

...

"a thing's a phallic symbol if it's longer than it's wide" -- Melanie

 

[hbjon]

No. The only concern about hydrogen is deflagration or detonation. Beyond that, the concern is the degraded condition of the fuel, which no longer confines the fission products. Beyond that is the degraded condition of the reactor coolant system which provides the next barrier between fission products and the environment. Beyond that is the degraded condition of the containment system which is the third barrier between fission products and the environment.

Proton fusion has a relatively low probability even in the center of the sun with a density of 160 g/cm³, 10 times that of lead, or 160 times that of water at 1 atm and ~25°C. The sun's core temperature of 15 million K (27 million °F) keeps it in a plasma state.

Normal condition in the BWR core is a mix of saturated liquid water and steam at ~286°C, with the cladding temperatures a bit hotter, and the fuel temperatures of 350-1400°C, where the highest temperature of the fuel is the centerline. In the current situation, the fuel temperature is much low, probably on the order of 200-400°C.

Oh geez, wow did I misspeak. Thanks astronuc, Your the bomb.

 

[Bez999]

Leads to some very interesting questions:
1. The refueling machine has narrower width than reactor opening. (Which is square).
2. Does this mean that fuel only can be stored in the SPF pool, since the refueling machine can't move to the other side of the reactor?
3. Can the "crane" turn around and operate on the other side (e.g. if there were tracks in the reactor concrete lid so the refueling machine could be restationed to the other side?)

Curios
Jens Jakob

Look again Jens, it appears this photo was taken from the SFP, with the machine standing over the reactor vessel. It looks like the perspective has you fooled, you can see the machine bridge tracks on the other side of the pool there.

 

[hidsuz]

Hi folks. Here in Tokyo and need to make a decision in the next few days. Stay and work but incur moving costs without knowing whether I`ll still end up having to leave, or simply quitting and starting from scratch back home. TEPCO, the govt, media, agenda based 'experts' simply cannot be trusted. Been reading this most excellent forum and, if I could oblige( I can start a different thread or try elsewhere if this is too OT), have some questions.

1)What is the worst case scenario?
2)What is most probable?
*and on what time frame to both

If I will most likely have to deal with ongoing radioactivity fears of the air, food, water and potential explosions on a day to day basis for years instead of months, it`d be an easy decision to leave. Thanks, I will try to provide any real time news.

 

[83729780]

I assume there is at least some connection? IE an increase in the level of radioactivity (becquerels) would normally result in a higher dose of radiation (sieverts)?

And if so, is it possible to estimate one from another, or is it just not feasable?

http://hps.org/publicinformation/ate/faqs/gammaandexposure.html" (with formulas)

http://www.radprocalculator.com/Gamma.aspx" (online calculator)

 

[TCups]

Look again Jens, it appears this photo was taken from the SFP, with the machine standing over the reactor vessel. It looks like the perspective has you fooled, you can see the machine bridge tracks on the other side of the pool there.

@Bez999

It looks to me like the fuel rods are in the chute, not the reactor. The lovely blue of the cherenkov radiation doesn't seem to open up any wider than the chute. The gates on the chute to both the SFP and the drywell containment are open, else I don't think you would see the blue color.

I can see what may be the rail for the fuel handling machine on the left extending back as far as the back of the chute, and presumably the opening over the reactor's core, but I cannot say it extends further.

The best diagrams I have do not show the rails for the fuel handling equipment extending over the equipment pool. Neither do I see any indication on the diagram for a chute between the back side of the drywell containment and the equipment pool.

http://i306.photobucket.com/albums/nn270/tcups/Oyster-Creek-reactor.gif

My understanding is that the equipment pool is used for storage of the reactor vessel cap (not the drywell cap) during the refueling process. It has been suggested to me by Astronuc the equipment on the floor at the back left corner might be the steam dryer (would that be radioactive?).

 

[razzz]

hidsuz: I'd start with a extended vacation starting immediately until they get some kind of control over the situation.

Drudge Report has a bunch of headlines up concerning the nuke situation, like...
http://chronicle.augusta.com/latest-news/2011-03-31/srs-concrete-pump-heading-japan-nuclear-site"

I'd say a 7.0 or larger quake and these boom trucks are toast if set up.

 

[Bez999]

@Tcups: Here's how I see that photograph. Take a ruler and place it alongside the SFP edge in the left of the picture to get a feel for the perspective. You'll see that the machine is actually wider than the SFP, contrary to what Jens suggested.
Also the fact that there is a gate shows that this is the SFP, not an equipment pool. Also, it is unlikely that reactor opening is square or rectangular rather than round or hexagonal, purely from a structural perspective. Hence, what we see is the SFP in the foreground and the reactor opening behind the gate, which also lines up with your comment about about the blue light.
In this picture the equipment pool would be behind the fuel handling handling machine.

The thing in the background looks like some tool that might be used to lift something out rather than being part of the reactor. It wouldn't surprise me if it was a jig to lift the steam dryer out with, don't know. I'd assume the steam dryer itself would be pretty active, but not to the degree it can't be lifted through the air to the equipment pool. One of the nuclear engineers here may know.

 

[TCups]

@Tcups: Here's how I see that photograph. Take a ruler and place it alongside the SFP edge in the left of the picture to get a feel for the perspective. You'll see that the machine is actually wider than the SFP, contrary to what Jens suggested.
Also the fact that there is a gate shows that this is the SFP, not an equipment pool. Also, it is unlikely that reactor opening is square or rectangular rather than round or hexagonal, purely from a structural perspective. Hence, what we see is the SFP in the foreground and the reactor opening behind the gate, which also lines up with your comment about about the blue light.
In this picture the equipment pool would be behind the fuel handling handling machine.

The thing in the background looks like some tool that might be used to lift something out rather than being part of the reactor. It wouldn't surprise me if it was a jig to lift the steam dryer out with, don't know. I'd assume the steam dryer itself would be pretty active, but not to the degree it can't be lifted through the air to the equipment pool. One of the nuclear engineers here may know.

@Bez999

1) Yes, of course the foreground is the SFP, not the equipment pool
2) Yes, obviously the fuel handling equipment doesn't float, so it has to be able to straddle the SFP to access the spent fuel below.
3) Functionally, the fuel handling machine must be able to shuttle from a position over the reactor access to a position over the SFP to effectively transfer fuel through water from the reactor to the SFP and back, through the transfer chute.
4) No, the fuel handling machine does not make the trip to the equipment pool (not shown in the picture)

Did you think I was suggesting otherwise? The point I was trying to make is this. I don't think operators could or would put new or spent fuel in the equipment pool even if they wanted to (as I think someone suggested might have happened), because:

1) the fuel handling machine doesn't go there.
2) the equipment pool is neither deep enough to accommodate fuel rod assemblies, nor does it have racks to hold them
3) there is no transfer chute between the equipment pool and the drywell containment
4) there is no need to store new (un-radiated) fuel rods in a pool as far as I know
5) if spent fuel rods were lifted through the air, as with the overhead crane instead of the fuel handling equipment, then the operators are exposed to dangerous levels of radiation

So, I conclude, there was nothing "dangerous" in the equipment pool on the north side of Bldg 3 before the chain of events that led to the explosion of Bldg 3, or to the possibility that the rod-like stuff on the north side of Bldg 3 came to be from fuel rods mysteriously placed in the equipment pool, and that maybe whatever that is in the back left corner may have been the source of the rod-like debris that have been the source of much debate.

See also: http://en.wikipedia.org/wiki/File:Reaktor.svg

 

[hidsuz]

hidsuz: I'd start with a extended vacation starting immediately until they get some kind of control over the situation.

Drudge Report has a bunch of headlines up concerning the nuke situation, like...
http://chronicle.augusta.com/latest-news/2011-03-31/srs-concrete-pump-heading-japan-nuclear-site"

I'd say a 7.0 or larger quake and these boom trucks are toast if set up.

hbjon, razzz, thanks for the input

link didn`t work for me( Drudge Report link did) but gist is:
"The world’s largest concrete pump, deployed at the construction site of the U.S. government’s $4.86 billion mixed oxide fuel plant at Savannah River Site, is being moved to Japan in a series of emergency measures to help stabilize the Fukushima reactors."

So if they are going to encase it like Chernobyl, I would imagine the local area, perhaps the present danger zone, will be off limits for quite a long time but that at least the rest of Japan will be able to function normally, assuming no more large explosions and gas leaks to come. However, they may be hoping to encase only 1-3 while shutting down safely the others. Wonder if it would even be feasible to encase all 6, especially with the seepage into ground water now. Read somewhere Chernobyl even now is in need of a new casing but at a cost of a billion the govt can`t afford it.

 

[Bez999]

@Tcups: I didn't think you suggested otherwise, I was responding to Jens' comment #2270, who appeared to suggest just that.

I agree that it's unlikely that operators would put fuel in the equipment pool, used or otherwise, for the reasons you already give, plus that the equipment pool doesn't have the racks to hold it securely in place. I'd think that those racks not only hold it in place, they also contain control rods or plates.

I agree also with your conclusion that there wasn't anything "ominous" in the equipment pool.

 

[Astronuc]

Hi folks. Here in Tokyo and need to make a decision in the next few days. Stay and work but incur moving costs without knowing whether I`ll still end up having to leave, or simply quitting and starting from scratch back home. TEPCO, the govt, media, agenda based 'experts' simply cannot be trusted. Been reading this most excellent forum and, if I could oblige( I can start a different thread or try elsewhere if this is too OT), have some questions.

1)What is the worst case scenario?
2)What is most probable?
*and on what time frame to both

If I will most likely have to deal with ongoing radioactivity fears of the air, food, water and potential explosions on a day to day basis for years instead of months, it`d be an easy decision to leave. Thanks, I will try to provide any real time news.

Most of the radioactivity maybe at the site, which is a problem for those at the site. The decay heat has been decreasing over three weeks, so it's not going to increase. The challenge is to remove the remaining heat so that pressure is managed, i.e. not increased.

I've not heard about the concrete system being moved from Savannah River to Fukushima. It's not enough to simply pour concrete into the SFPs or containment. If it's done incorrectly it can crack and develop porosity.

Look on http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm for readings of radioactivity. I'm still looking for more information myself.