Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[TCups]

There's a lot of debris on that 1 storey building, so the damage is likely to be from the number 1 blast?
However there is a strange line down one side of unit 2, the side with the agping hole venting steam, anyone else noticed that?

Yes. There were also previous close ups of Bldg 2 that show the cracks (pleural) as well as several small holes in the roof venting small amounts of smoke or steam, in addition to the sizable hole in the east face of Bldg 2 as I recall.

 

[NUCENG]

There's a good video on youtube called inside the sarcophagous. They were pretty concerned about the contents reforming a shape that was 'critical' at chernobyl months after the accident, and went inside to investigate exactly where all the fuel had gone. When they finally saw inside the core it was empty!

I have seen a 60 Minutes episode where the entered the plant exploring the lower levels of the building below where the reactor core was. They discovered a fossilized flow of melted sand (glass) and core materials that they have nicknamed the "elephant' foot." The most memorable thing on that show was that the Russians monitoring the plant tended to leave their personal dosimetry behind when they went inside the sarcophogus. They didn't want to get a dose that required them to leave the site.

That is similar to the lessons from Three Mile Island. In the midst of the event it was hard to get people to leave because they all wanted to help. Similarly, the stories of the "50 heroes" at Fukushima Daiichi.

 

[timeasterday]

I have seen a 60 Minutes episode where the entered the plant exploring the lower levels of the building below where the reactor core was. They discovered a fossilized flow of melted sand (glass) and core materials that they have nicknamed the "elephant' foot." The most memorable thing on that show was that the Russians monitoring the plant tended to leave their personal dosimetry behind when they went inside the sarcophogus. They didn't want to get a dose that required them to leave the site.

That is similar to the lessons from Three Mile Island. In the midst of the event it was hard to get people to leave because they all wanted to help. Similarly, the stories of the "50 heroes" at Fukushima Daiichi.

I remember one part of the Youtube video where they describe getting a sample of the elephant's foot by shooting at it with an AK-47!

 

[Gilles]

how to say without saying...

http://www.bloomberg.com/news/2011-03-30/record-high-levels-of-radiation-found-in-sea-near-crippled-nuclear-reactor.html

Japan’s Nuclear and Industrial Safety Agency said there’s no possibility of uncontrolled chain reactions.

they exclude the possibility of uncontrolled chain reactions , but not of chain reactions ! obvisously , if some occur, they can be only transient and without much power, since the whole thing has not yet exploded. The intrinsic kinetics of chain reactions implies a negative feedback adjusting the level close to near-criticality. I'm not sure that the scenario I sketched https://www.physicsforums.com/showpost.php?p=3214771&postcount=1697" :) ) but something similar should happen if the presence of neutrons in confirmed.

 

[TCups]

EXTENT OF DAMAGE TO REACTOR BUILDINGS DUE TO EARTHQUAKE?


Have there been any reports of the extent and types of earthquake damage that occurred at other regional NPP's that didn't suffer catastrophic consequences of complete loss of power?

Perhaps this point was already made, but if so, I make it again. A 9.0 earthquake, in and of itself, could do significant damage to the reactor buildings. The scenarios I and others have considered in most detail follow the consequences of complete loss of all power and subsequent events related to the reactor vessels, primary containment, and spent fuel pools.

The chain of events at Fukushima with the rapid arrival of the tsunami and complete loss of power were such that, if done, there has been little or no reporting of a primary assessment of damages or likely damages due solely to the magnitude of the earthquake. Significant lateral thrusting occurred.

I am reminded of the external crack visible on Bldg 2 and must wonder if they are blast or earthquake-related, or more likely, a combination of both.

Also, in cross-section, the arrangement of a massive concrete and steel primary containment structure nested atop a huge underground torus leads me to wonder what damages the quake might have caused by the extreme forces of lateral thrusting where the two structures meet, so to speak.

Some knowledge of the specific types and locations of damages that might have been in play at Fukushima at the time power was lost would surely be helpful in sorting out what has followed.

 

[chrget]

[...]
be interesting to get hold of GE report being referenced

Hmmmm, might it be http://www.osti.gov/bridge/purl.cover.jsp?purl=/6402578-Rr9xTe/", by any chance?

Regards,
Chris.

 

[AntonL]

Hmmmm, might it be http://www.osti.gov/bridge/purl.cover.jsp?purl=/6402578-Rr9xTe/", by any chance?

Regards,
Chris.

Chris welcome - one of the most contributing first posting - looking forward to your next contribution

 

[artax]

We need more images to discuss, that bit was fun.
here's a higher res one
http://cryptome.org/eyeball/daiichi-npp/pict10.jpg
and

http://cryptome.org/eyeball/daiichi-npp/pict7.jpg

and no 4

http://www.journal.lu/wp-content/uploads/2011/03/35_063_2col_NB_p09_839862.jpg
and brownsferry construction

http://i700.photobucket.com/albums/ww1/indoorcarnivore/Browns_Ferry_Unit_1_under_construction.jpg

 

[chrget]

Chris welcome - one of the most contributing first posting - looking forward to your next contribution

Thank you very much. I doubt I can offer all that much input regarding the physical aspects, though. So it was more or less a lucky Google hit.

Speaking of which, I think I found the actual document in question, which is only referenced by the one I mentioned earlier: http://www.ornl.gov/info/reports/1981/3445600211884.pdf"

Regards,
Chris.

 

[TCups]

EARTHQUAKE DAMAGE AT THE TORUS - PRIMARY CONTAINMENT INTERFACE?

With the very limited knowledge I have regarding building to earthquake code, I seem to recall that one of the fundamental approaches is to build foundations that allow for lateral movement of the ground under the building with foundations that "float".

With the limited information available to me regarding the construction of the BWR's of the type at Fukushima, it would appear that a huge torus suppression pool underground and a massive concrete and steel primary containment nested in it would not tend to "float" side to side with the lateral forces of a 9.0 earthquake. Instead, it would seem to me that the arrangement would be more like a bowling pin sitting in a bowl. One could hypothesize that the most likely stress point might be where the torus and primary containment meet.

This might help explain

1) failure of Unit 2 in the torus suppression pool region
2) some of the explosive damages in the lower levels of Unit 3

But it would not explain

3) explosive damages in the lower levels of Unit 4

Comments?

 

[PietKuip]

how to say without saying...

http://www.bloomberg.com/news/2011-03-30/record-high-levels-of-radiation-found-in-sea-near-crippled-nuclear-reactor.html



they exclude the possibility of uncontrolled chain reactions , but not of chain reactions ! obvisously , if some occur, they can be only transient and without much power, since the whole thing has not yet exploded. The intrinsic kinetics of chain reactions implies a negative feedback adjusting the level close to near-criticality. I'm not sure that the scenario I sketched https://www.physicsforums.com/showpost.php?p=3214771&postcount=1697" :) ) but something similar should happen if the presence of neutrons in confirmed.

I looked att the graphs (! very rare in Tepco publications) in http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110330e13.pdf

The ratios of the isotope concentrations are varying a bit, but there is no obvious faster decline of the short-lived ones in the last week. Which may indicate that fission is ongoing.

 

[curie]

Thanks curie,

So these methods can detect all radio-isotopes, (plutonium, cesium, etc...) in soft tissue, like the lung, thyroid, etc... ?

Rhody...

A combination of biological monitoring (which is monitoring of the body's output: faeces, urine, saliva, nasal secretions, etc) and direct external monitoring will be able to detect pretty much any isotopes if they have been taken into the body and not already passed through or decayed. There are some more invasive monitoring techniques like lung lavage which are rarely used. Good estimates of body burden can be made. These techniques have been used not only in routine nuclear/rad work & accident/research purposes but for nuclear medicine procedures too so they are well established.

 

[|Fred]

thx artax :)
here is the link to the full res http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.zip

 

[TCups]

thx artax :)
here is the link to the full res http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.zip

VISIBLE MAJOR STRUCTURAL DAMAGES AFTER EARTHQUAKE BUT BEFORE EXPLOSIONS?

@Fred:
included in your photo summary files, ... 12.jpg

The south face of Bldg 1 has a huge diagonal crack. That looks a lot more like possible damage from the lateral thrust forces of a 9.0 quake than an explosion, IMO.

Addendum CORRECTION:

Bloop! There is wasn't. The "What?" that I wasn't seeing before -- shadows from the stairs.

March 12, March 18 images confirm the crack at the base of the south face of Bldg 2. Look closely at the south face of Bldg 4 before the explosion!

Image source for last two images: DigitalGlobe.com

 

[artax]

thx artax :)
here is the link to the full res http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.zip

Cheers Fred, they're great!

 

[Joe Neubarth]

The sea water samples with highest radiation levels are taken 330 metres south - the yellow line is 330 metres according to google.

They need to take their samples out on the end of that rock and cement Quaywall extending to the right in the photo..

Looking at the swell action you can see the waves coming in at the bottom of the photo. That usually equates to water coming in from the ocean at that point. The absence of swells right at the plant effluent area suggests water flowing out to sea (path of least resistance. I'm an avid body surfer and know how to look for rip currents.) I am willing to bet that their strongest radioactive contamination will be along that quaywall

 

[timeasterday]

VISIBLE MAJOR STRUCTURAL DAMAGES AFTER EARTHQUAKE BUT BEFORE EXPLOSIONS?

@Fred:
included in your photo summary files, ... 12.jpg

The south face of Bldg 1 has a huge diagonal crack. That looks a lot more like possible damage from the lateral thrust forces of a 9.0 quake than an explosion, IMO.

Addendum:

Bang! There it is! The "What?" that I wasn't seeing before.

March 12, March 18 images confirm the crack at the base of the south face of Bldg 2. Look closely at the south face of Bldg 4 before the explosion!

Image source for last two images: DigitalGlobe.com

That looks more like a pipe or some other manmade structure. It's a straight diagonal line with what may be a shadow that makes it look a little deeper.

EDIT: upon closer inspection all I see is a stairway.

 

[artax]

VISIBLE MAJOR STRUCTURAL DAMAGES AFTER EARTHQUAKE BUT BEFORE EXPLOSIONS?

@Fred:
included in your photo summary files, ... 12.jpg

The south face of Bldg 1 has a huge diagonal crack. That looks a lot more like possible damage from the lateral thrust forces of a 9.0 quake than an explosion, IMO.

Addendum:

Bang! There it is! The "What?" that I wasn't seeing before.

March 12, March 18 images confirm the crack at the base of the south face of Bldg 2. Look closely at the south face of Bldg 4 before the explosion!

Image source for last two images: DigitalGlobe.com

I think your diagonal crack is where the stairs were ... look at building 2 in your first image there.

still examining these fascinating images!

 

[timeasterday]

I think any theories of the cap being blown off reactor 3 can be put to bed now. You can clearly see the steel girder framework largely intact over most of the building. If you look closely at photo "aerial-2011-3-30-0-50-20.jpg" you can see the greenish color of the SFP (at least I think that's it).

 

[artax]

I think any theories of the cap being blown off reactor 3 can be put to bed now. You can clearly see the steel girder framework largely intact over most of the building. If you look closely at photo "aerial-2011-3-30-0-50-20.jpg" you can see the greenish color of the SFP (at least I think that's it).

We could really do with a plan veiw of where the reactor is in relation to the cube. Yes if it's in the centre then I aggree but where you can see the green of possibly the crane... which is what I thought it was, there's an obvious hole been blown through everything. possibly the SFP being so heavily built. strong and deep it directed the hydrogen explosion in an upwards direction, piercing like a shaped charge and sending a bit of the roof up.?

 

[liamdavis]

EXTENT OF DAMAGE TO REACTOR BUILDINGS DUE TO EARTHQUAKE?


Have there been any reports of the extent and types of earthquake damage that occurred at other regional NPP's that didn't suffer catastrophic consequences of complete loss of power?

Perhaps this point was already made, but if so, I make it again. A 9.0 earthquake, in and of itself, could do significant damage to the reactor buildings. The scenarios I and others have considered in most detail follow the consequences of complete loss of all power and subsequent events related to the reactor vessels, primary containment, and spent fuel pools.

The chain of events at Fukushima with the rapid arrival of the tsunami and complete loss of power were such that, if done, there has been little or no reporting of a primary assessment of damages or likely damages due solely to the magnitude of the earthquake. Significant lateral thrusting occurred.

I am reminded of the external crack visible on Bldg 2 and must wonder if they are blast or earthquake-related, or more likely, a combination of both.

Also, in cross-section, the arrangement of a massive concrete and steel primary containment structure nested atop a huge underground torus leads me to wonder what damages the quake might have caused by the extreme forces of lateral thrusting where the two structures meet, so to speak.

Some knowledge of the specific types and locations of damages that might have been in play at Fukushima at the time power was lost would surely be helpful in sorting out what has followed.

According to this site, which keeps a running tally, as of my posting time there have been
851 quakes >4M
402 quakes >5M
51 quakes >6M
and 3 quakes >7M just since March 11, 2011.

http://www.japanquakemap.com/

By the time you go to the site it will have increased.

Over the 40 years of their operation how many quakes have the Daiichi plants endured? What ever the number it is remarkable. It may also have taken a toll that would have been very informative to analyze after decommissioning. What we cannot know is if those cumulative stresses brought some components too close to failure to withstand the latest combination of events.
liam

 

[timeasterday]

We could really do with a plan veiw of where the reactor is in relation to the cube. Yes if it's in the centre then I aggree but where you can see the green of possibly the crane... which is what I thought it was, there's an obvious hole been blown through everything. possibly the SFP being so heavily built. strong and deep it directed the hydrogen explosion in an upwards direction, piercing like a shaped charge and sending a bit of the roof up.?

Yeah, that could be what happened. I'm still a bit puzzled over the #3 explosion. In the video you can clearly see a large fireball come out of the south side (supposedly where the SFP is) and then it gets sucked back in before a large upward blast that seemed more centered in the building. In the photos the roof is pretty much gone over the north and south ends but still over the middle.

 

[TCups]

VISIBLE STRUCTURAL CRACKS IN SOUTH FACE OF BLDG 2, 4 - NOT CORRECT

I think your diagonal crack is where the stairs were ... look at building 2 in your first image there.

still examining these fascinating images!

#artax:

Oops. Must agree. Stairs. Shadows account for the apparent differences. Back to the drawing board, I guess. . .

SEE ATTACHED IMAGES:

 

[Joe Neubarth]

EXTENT OF DAMAGE TO REACTOR BUILDINGS DUE TO EARTHQUAKE?


Have there been any reports of the extent and types of earthquake damage that occurred at other regional NPP's that didn't suffer catastrophic consequences of complete loss of power?

Perhaps this point was already made, but if so, I make it again. A 9.0 earthquake, in and of itself, could do significant damage to the reactor buildings. The scenarios I and others have considered in most detail follow the consequences of complete loss of all power and subsequent events related to the reactor vessels, primary containment, and spent fuel pools.

The chain of events at Fukushima with the rapid arrival of the tsunami and complete loss of power were such that, if done, there has been little or no reporting of a primary assessment of damages or likely damages due solely to the magnitude of the earthquake. Significant lateral thrusting occurred.

I am reminded of the external crack visible on Bldg 2 and must wonder if they are blast or earthquake-related, or more likely, a combination of both.

Also, in cross-section, the arrangement of a massive concrete and steel primary containment structure nested atop a huge underground torus leads me to wonder what damages the quake might have caused by the extreme forces of lateral thrusting where the two structures meet, so to speak.

Some knowledge of the specific types and locations of damages that might have been in play at Fukushima at the time power was lost would surely be helpful in sorting out what has followed.

AT Fukushima the degree of shaking was not anywhere near a 9.0.

It might have been equivalent to a 6.0 or less.

 

[AntonL]

They need to take their samples out on the end of that rock and cement Quaywall extending to the right in the photo..

Looking at the swell action you can see the waves coming in at the bottom of the photo. That usually equates to water coming in from the ocean at that point. The absence of swells right at the plant effluent area suggests water flowing out to sea (path of least resistance. I'm an avid body surfer and know how to look for rip currents.) I am willing to bet that their strongest radioactive contamination will be along that quaywall

Joe you 100% correct , a rip will be set up along the breakwater due to the swell action, the sampling point is such as not to expose the sampler unnecessarily to radiation, you can actually see a track leading down to the beach on the land side. Any way nobody will be body-surfing there for a very very long time, cesium being heavy will settle and embed itself into the moving sand

Body surfing, reading the waves and staying safe in a ocean with 3 meter plus waves is also one of my specialties

 

[jlduh]

Concerning the Tcups remark about the possible weak point being at the junction between the torus and the "pear" vessel, especially if you consider the necessity to "float" to some extent for resisting to quakes, as a mechanical engineer i must admit that for me, as i feel it, there is probably a weak point at the radial pipes connecting the torus and the vessel.

The way this design works, which has to be at the same time floating (to be resilient) and very rigid because of the mass of concrete around the vessel to make it resistent from the containment standpoint, is not clear for me...

I saw on several drawings that the torus sits on some strange supports (like fins below it) and I'm wondering if this would be to allow for some movement of it in case of quake? Also i see on this sketch some parts (orange) at the middle of the pipes joining the vessel and the torus: are these some kind of "joints" allowing for some kind of expansion or relative movement?
http://www.netimago.com/image_184623.html

We see these kind of "articulated" joints (or thermal expansion joints) on this picture:

http://i700.photobucket.com/albums/ww1/indoorcarnivore/Browns_Ferry_Unit_1_under_construction.jpg

Something to consider, maybe it has been documented in the past studies, and maybe that was one of the reasons to get rid of the torus in newer designs...

I've seen written that the concerns where about loads at the suppression chamber that were not taken into account in the first design, but it was more about thermodynamic loads it seems (when transient spikes happen in terms of temperature and pressure), that's why they added elements in the SP to diminish the size of the steam bubbles and so the loads. Don't know about the quake loads.

I think you saw this info some days ago, from IAEA revealed by wikileaks:
http://www.indianexpress.com/news/iaea-warned-japan-over-nuclear-quake-risk-wikileaks/763709/

An other remark on the black and white picture above showing the pressure vessel and the torus being built: many many pipes going out of the containment vessel, this is also a weak design from this standpoint.

A different subject with an other confirmation on this plot: the core pressure in reactor N°1 continues to rise dangerously...

http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/v6/plot-un1-full.png

 

[TCups]

DO WE KNOW THE FORCE OF THE EARTHQUAKE AND EXTENT OF POSSIBLE DAMAGES TO THE FUKUSHIMA SITE BEFORE THE TSUNAMI?

AT Fukushima the degree of shaking was not anywhere near a 9.0.

It might have been equivalent to a 6.0 or less.

Really? References? It would help to know for sure.

6.0 vs 9.0 would certainly have been one helluva difference - what? a factor of 32 for each full point on the Richter scale, correct? or 1024X less powerful at the Fukishima site than the reported 9.0 quake at the epicenter. Maybe.

Is the magnitude on the Richter scale related to the total duration of the quake event? That is, does a "6.0 quake" that lasts for 2 full minutes instead of 30 seconds measure higher on the Richter scale?

Does anyone know what the quake-resistant structure of a NPP might be? It doesn't appear to be a floating slab foundation at first glance.

Is complete loss of the primary power grid and water sloshing out of the SFP in large quantities, dousing one of the workers (as per his first hand account) common in a 6.0 quake? If not, what brought down the power lines or power before the tsunami hit? Didn't I read that the shore line had shifted almost a meter after the quake in some places along the coast?

 

[AntonL]

AT Fukushima the degree of shaking was not anywhere near a 9.0.

It might have been equivalent to a 6.0 or less.

I read somewhere actually around 7 for the site

but https://www.physicsforums.com/showpost.php?p=3218366&postcount=1989"

so the horizontal acceleration due the earthquake at Daiichi was 507 gal, 1 gal being 1 cm/s^2 that means an acceleration of 5m/s^2. That is a lot.

 

[Joe Neubarth]

DO WE KNOW THE FORCE OF THE EARTHQUAKE AND EXTENT OF POSSIBLE DAMAGES TO THE FUKUSHIMA SITE BEFORE THE TSUNAMI?



Really? References? It would help to know for sure.

6.0 vs 9.0 would certainly have been one helluva difference - what? a factor of 32 for each full point on the Richter scale, correct? or 1024X less powerful at the Fukishima site than the reported 9.0 quake at the epicenter. Maybe.

Does anyone know what the quake-resistant structure of a NPP might be? It doesn't appear to be a floating slab foundation at first glance.

Is complete loss of the primary power grid and water sloshing out of the SFP in large quantities, dousing one of the workers (as per his first hand account) common in a 6.0 quake? If not, what brought down the power lines or power before the tsunami hit? Didn't I read that the shore line had shifted almost a meter after the quake in some places along the coast?

T, I live in southern California. I have been through hundreds and hundreds of 5.0 earthquakes just a hundred miles away that I could not even feel. Distance definitely dampens the effect. Now, if a building is built upon fill or soft soil (clay and water) a building fifty miles from the quake can rock and roll and collapse if it is not structurally sound.

A 5.0 earthquake can bring down power lines if it unleashes boulders from a hillside and they take out the electrical grid transmission tower. Anything like that can happen.

The biggest issue, of course in Japan was that their grid fell apart with all of the nuclear power plants on the north side of that large island going to shutdown mode (SCRAMS) during a part of the day when demand was high. Circuit breakers open and whole regions are without power.

 

[TCups]

T, I live in southern California. I have been through hundreds and hundreds of 5.0 earthquakes just a hundred miles away that I could not even feel. Distance definitely dampens the effect. Now, if a building is built upon fill or soft soil (clay and water) a building fifty miles from the quake can rock and roll and collapse if it is not structurally sound.

A 5.0 earthquake can bring down power lines if it unleashes boulders from a hillside and they take out the electrical grid transmission tower. Anything like that can happen.

The biggest issue, of course in Japan was that their grid fell apart with all of the nuclear power plants on the north side of that large island going to shutdown mode (SCRAMS) during a part of the day when demand was high. Circuit breakers open and whole regions are without power.

J:
I lived in Cape Giradeau, MO for 13 years near the epicenter of the New Madrid fault. The fault lines on the west coast of North America, particularly in California, are in a geographic region where the substructure is basically crushed rock. Like Japan, I believe, the fault line is a subduction zone with the Pacific plate diving under the NA Plate. Major earthquakes on the west coast don't have linear propagation of energy for long distances. On the other hand, major earthquakes along the New Madrid Fault are on a substructure of granite, and the fault line is along abutting plates. When they break loose, like in the early 1800, quakes in Missouri rang church bells in Philadelphia. An 8.0 in New Madrid would be an 8.0 in Memphis and St. Louis. I don't know that you can draw the conclusion that the force of the quake was diminished at Fukushima, but in any case, the hard data would be good to know.

You are of course correct about the probable reasons for loss of power.

 

[DSamsom]

Hi, new in this very useful forum.

Can somebody help me understanding what is happening in reactor 1 these days/hours. The Temperature dropped a little, but the core pressure keeps rising. What could be the explanation?

 

[Reno Deano]

Some information on TMI Upgrades that Units 1, 2, 3, and 4 should have implemented by TEPCO. There is no reason or information that they did not implement these modifications. This data can give insight to reasons for the uncontrolled hydrogen releases and why reactor vessel water levels could not be ascertained after the Station Blackout hit.

From NUREG-0737, POST-TMI REQUIREMENTS FOR OPERATING REACTORS

http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0737/final/sr0737.pdf"

These requirements cover, among other things, RPV and Containment relief valves, hydrogen gases control, reactor water level determination, high range radiation monitors in-plant and quantative radiochecmistry analysis off reactor coolants, auxillary feed water system improvements, reactor containment isolation, back up emergency AC and Battery power for possible Station Black Out conditions, etc. Due to the plants experiencing a prolonged Station Blackout, most of the system failed safe.

Excerpt from Table of Contents:

II.F.2 Instrumentation for
detection of
inadequate core
cooling

II.F.1 Accident-monitoring
1. Noble gas monitor
2. Iodine/particulate sampling
3. Containment high-range monitor

II.F.2 Instrumentation for detection of
inadequate core cooling
4. Containment pressure
5. Containment water level
6. Containment hydrogen

 

[Joe Neubarth]

Hi, new in this very useful forum.

Can somebody help me understanding what is happening in reactor 1 these days/hours. The Temperature dropped a little, but the core pressure keeps rising. What could be the explanation?

They are pumping more water in.

 

[curious11]

Sorry if this subject has already been put to bed. I thought I'd use the latest hi-res images to locate the position of the suspected sf-rods from an earlier video.

So, here they are. Any idea what the feature hi-lighted might be?

 

[artax]

Hi, new in this very useful forum.

Can somebody help me understanding what is happening in reactor 1 these days/hours. The Temperature dropped a little, but the core pressure keeps rising. What could be the explanation?

No Idea, How much has the pressure increased or how quickly is it rising, and where are they measuring it... the last I heard (Wiki) they thought 1,2 and 3 had cracks in the containment, or was it the pressure vessel I just read.
Anyone know how high the reactor buildings are...(were!) I want to work out how high that concrete went in the blast at number 3.

 

[jensjakob]

TCups, I can't find the "fuelrods" on the new hi-res images...

Can you?

If they are gone, someone knows what they were...

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

 

[artax]

Sorry if this subject has already been put to bed. I thought I'd use the latest hi-res images to locate the position of the suspected sf-rods from an earlier video.

So, here they are. Any idea what the feature hi-lighted might be?

https://www.physicsforums.com/attachment.php?attachmentid=33787&stc=1&d=1301584597

Well we've sort of come to the conclusion that all four buildings have the Spent Fuel Pool at the south side of the building/reactor. So if that's true I don't know what those rods are as they are on the North side... but they sure look like the way they were described on Radio 4 last week, about as thick as your finger and 4 meters long!
So maybe they had so many they were storing them everywhere in the less robust tanks around the place. It seems the Americans and no doubt many countries are just saving them up for a rainy day!
It's a shame they can't just hand them out to housholds to chuck in the bath when you need some hot water!

 

[Borek]

So, here they are. Any idea what the feature hi-lighted might be?

Fits our latest photography competition perfectly.

Looks like a pipe to me. Tons of pipes around.

 

[curious11]

Well we've sort of come to the conclusion that all four buildings have the Spent Fuel Pool at the south side of the building/reactor. So if that's true I don't know what those rods are as they are on the North side... but they sure look like the way they were described on Radio 4 last week, about as thick as your finger and 4 meters long!
So maybe they had so many they were storing them everywhere in the less robust tanks around the place. It seems the Americans and no doubt many countries are just saving them up for a rainy day!
It's a shame they can't just hand them out to housholds to chuck in the bath when you need some hot water!

Well they certainly aren't near the sfp. Do we have a schematic to overlay on this aerial photo? Maybe they're other elements used to space-out/organise the actual rods; ie benign?

 

[artax]

@ Jenskabob, I'm pretty sure curious ! has located the place... they're just too small to see.

 

[artax]

Well they certainly aren't near the sfp. Do we have a schematic to overlay on this aerial photo? Maybe they're other elements used to space-out/organise the actual rods; ie benign?

I've been searching all day for an overhead plan of one of these reactors with the different floors schematicked. (if that's a word)
I still think it's likely that they had loads of 'FAIRLY COLD' rods that they just thought they'd store in the nearest pool of water, I mean no-one's going to know... unless there's a massive Tsunami next week!
You know what industry is like.

 

[83729780]

http://lewis.armscontrolwonk.com/files/2011/03/Cause_of_the_high_Cl38_Radioactivity.pdf"

Conclusions

So we are left with the uncomfortable realization that the cause of the Cl-38 concentrations is not due to seawater
intercepting neutrons from natural spontaneous fission of the used nuclear fuel. There has to be another reason.

Assuming that the TEPCO measurements are correct, the results of this analysis seem to indicate that we cannot
discount the possibility that there was another strong neutron source during the time that the workers were sending
seawater into the core of reactor #1. However, since we don’t know the details of the configuration of the core
and how the seawater came in contact with the fuel it is difficult to be certain. Given these uncertainties
it is nonetheless important for TEPCO to be aware of the possibility of transient criticalities when work is being done;
otherwise workers would be in considerably greater danger than they already are when trying to working to contain
the situation. A transient criticality could explain the observed 13 “neutron beams” reported by Kyodo news agency
(see above). This analysis is not a definitive proof but it does mean that we cannot rule localized criticality out
and the workers should take the necessary precautions.

 

[artax]

very interesting link thanks.
Will have to read it tomorrow.

 

[curious11]

I've been searching all day for an overhead plan of one of these reactors with the different floors schematicked. (if that's a word)
I still think it's likely that they had loads of 'FAIRLY COLD' rods that they just thought they'd store in the nearest pool of water, I mean no-one's going to know... unless there's a massive Tsunami next week!
You know what industry is like.

Or. they;re just control rods... ?

http://www.sciencephoto.com/images/download_lo_res.html?id=841700465"

 

[gmax137]

TCups, I can't find the "fuelrods" on the new hi-res images...

Can you?

If they are gone, someone knows what they were...

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.

 

[TCups]

Sorry if this subject has already been put to bed. I thought I'd use the latest hi-res images to locate the position of the suspected sf-rods from an earlier video.

So, here they are. Any idea what the feature hi-lighted might be?

https://www.physicsforums.com/attachment.php?attachmentid=33787&stc=1&d=1301584597

@Curious

You have indeed located the rod-like objects in the latest areal imagery. This was taken from the first helicopter fly over, and by way of disclosure, "Photoshop'ed" to correct color levels, contrast, and sharpness

http://i306.photobucket.com/albums/nn270/tcups/903a9527.jpg

And here is my best SWAG at the layout of the top floor, see post #2089

https://www.physicsforums.com/attachment.php?attachmentid=33731&d=1301513587

which puts the "rod-like structures west of the location of the equipment pool, I believe. I am not sure of the confirmation of my layout in the second image, however.

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.

Yes, but not anywhere else in a fairly tight cluster that I can see. And in the midst of explosive destruction, they seem awfully rigid -- not bent like lots of the rebar seen in other images.

 

[TCups]

T, I live in southern California. I have been through hundreds and hundreds of 5.0 earthquakes just a hundred miles away that I could not even feel. Distance definitely dampens the effect. Now, if a building is built upon fill or soft soil (clay and water) a building fifty miles from the quake can rock and roll and collapse if it is not structurally sound.

A 5.0 earthquake can bring down power lines if it unleashes boulders from a hillside and they take out the electrical grid transmission tower. Anything like that can happen.

The biggest issue, of course in Japan was that their grid fell apart with all of the nuclear power plants on the north side of that large island going to shutdown mode (SCRAMS) during a part of the day when demand was high. Circuit breakers open and whole regions are without power.

Joe:

I draw your attention to Astronuc's earlier post at 1989. At the time, I was not smart enough to understand what Astronuc was telling us. The lateral acceleration recorded at unit 3 exceeded the design maximum for lateral ground motion acceleration in the east-west axis, ie, in the direction of propagation of the energy from the epicenter of the quake.

Quoting in part, from Astronuc's reference source:

"At Daiichi there is still no data for units 1, 2 and 5, but available figures put the maximum acceleration as 507 gal from east to west at unit 3. The design basis for this was 441 gal. Other readings were below design basis, although east-west readings at unit 6 of 431 gal approached the design basis of 448 gal."

I am also informed that 1 gal = 1 cm/sec² and 500 gal = 1 m/sec²

I've been wondering about the ground motion and accelerations. Apparently not all the data are collected and/or processed, but from WNN,

http://www.world-nuclear-news.org/RS_Fukushima_faced_14-metre_tsunami_2303113.html

No mention of unit 4.

From - http://www.world-nuclear.org/info/inf18.html

 

[jlduh]

Thanks FRED for these excellent quality pictures, taken it seems the 20th and the 24 th of March by a Canon KissX4 (which is in fact the 550D in Japan) and a Canon 5D MarkII (based on the exifs of the pictures... i practice photography so it's an habit to check that).

I guess these are the ones take by the Japanese Air Service in Nigata with the small plane used also for volcanoes. Where did you find them by the way?

As everybody i started to review them in detail. On buiding 3, i have something which ressembles to the cover of the pressure vessel, on this capture:

http://www.netimago.com/image_184641.html

extracted from this full res image:

http://www.netimago.com/image_184667.html

Do you see this big yellow round part which is right behind the pillar n°4, right in the middle of the building from this view taken from the East side?

I've been at first in favor of the theory of the concrete plus being ejected by the huge vertical explosion, but looking at the top and at the way the explosions precisely happened on the video, I rejected this idea. Now i see this picture and I wondering what this part is, right here...

And then, where would have gone the big concrete plug? Just moved sideways maybe?

I'm in the position of really saying that there hasn't been big ejections at the vertical of this point above the reactor well. But maybe displacement?

Could it be that there may be a second cover that was on the top floor for maintenance reasons for example?

 

[Joe Neubarth]

http://lewis.armscontrolwonk.com/files/2011/03/Cause_of_the_high_Cl38_Radioactivity.pdf"

Some time ago I brought up the issue of injecting sea water into the reactor for cooling sake. At that time all of the articles that I read (perhaps fifty or sixty) mentioned injection of sea water into the core and never mentioned boron treatment. Our moderator was kind enough to copy several that were available to him. Obviously, he was reading the right articles. Then I noticed a post with the boron information struck through and then an article that said they injected the boron AFTER the sea water.

If so I am quite certain they managed to flush enough boron from the reactor so as to ensure an increase in the thermal neutrons available for fission, and probably created a temporary (transient) criticality in the high energy pulsating blob that used to be the reactor core.

There is no way of knowing, of course, short of data telemetry that would have recorded the increase in all types of radiation at the scene near the time they were injecting sea water that was not already mixed with boron. That most certainly will account for the oddities associated with Reactor One.

 

[rmattila]

We've been taking some air samples here in Finland, with preliminary results suggesting Cs-134/137 activity ratios of the order of 1,05. Having no idea of what kind of core design they are using at Fukushima, we made some rough calculations of isotopic concentrations of "typical" BWR assembly at different void histories (see example below).

What we're hoping is to try to see, if it would be possible to estimate the extent of core damage based on isotopic ratios of nuclides from different samples. Like, if it would seem that the measured isotopic ratios correspond to the void history in the top of the core rather than the core average, or the burnup in the most powerful assemblies vs. core average etc.

I wonder if anybody else is doing anything similar, and if someone would have better information on the fuel/reload strategy used in the accident reactors.