Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[downwinder]

My only agenda is to get to the truth of the matter at hand.

If there were criticality events, the inventory associated with MW-s/MTU are quite small relative to the existing inventory.

I have stared at levels of 100 msv/hr many times and am no stranger to the events that are happening. As I have been following the events for the last couple of weeks on this site and elsewhere, I have concluded that the radiation levels are so intense that no one is able to gather the facts, evidence or pictures to conclude just exactly what has occurred, what the current conditions are and how they are going to get this under control. I suspect that the debris is such that no robots will be able to penetrate the debris field to obtain required information to access the situation. This may go on until decay heat and radiation levels subside or they just decide to pour concrete over the whole thing and dedicate it as a shrine to nuclear power. If they do that it will be interesting is to see how the ground water issue is resolved.

If you are looking for MW-s/MTU as an indication of a criticality in the reactors or fuel pools you never did the sub critical experiments in your MS engineering curriculum. It just takes a pulsed fission event to deplete the moderator or geometry to shut the event down only to reoccur when the geometry is again favorable. I would not find comfort in the fact that the power level is small relative to the reactor operating levels.

 

[I_P]

For reference, Wikipedia has a decent time lines and overall information combined together.

http://en.wikipedia.org/wiki/Fukushima_I_nuclear_accidents"

[PLAIN]http://upload.wikimedia.org/wikipedia/commons/a/a1/Bwr-rpv.svg[/QUOTE]

Wiki summarizes the public statements and conjectures from official sources, however the timeline is incomplete and all statements about the condition of units 1-4 are inferential. Measurements of radiation levels are spotty and incomplete as TEPCO's monitoring system went offline after the earthquake. Some data was intermittently collected by workers driving around in a car, however the data collected is insufficient to characterize the releases and changes in background levels.

There has been no entry into the damaged units, no photos released of building interiors (except a few inadequate shots of unit 4), it is uncertain what monitoring systems are delivering reliable data - most systems are offline due to damage. Radiation measurements taken by workers have been subject to revision after the fact...

Regarding unit 4 the Wiki timeline speaks of an explosion on March 15th that left 2 8m square holes in the walls (I recall the statements as 1 in a wall and one in the roof), however the current state of the structure shows massive damage - when and how did this occur?

Radiation levels spiked at the prefecture monitoring stations early on March 21st and are only now returning to where they were on the 19th. TEPCO said pressure was rising in unit 3 on the 20th and suggested they might need to vent it - but then the levels declined without intervention and now the containment is at atmospheric pressure... what happened? No statements have been forthcoming other than some waffling about the state of containment.

What is the state of the fuel storage pools in units 1,3,and 4 given the explosive destruction we can see in the aerial photos?

Workers cannot access many areas of the site because of high radiation levels - what are the sources?

 

[razzz]

So the I-134,Tellurium, lanthanum products and chlorine-38 readings are all wrong?

I don't believe it,but if true its very disturbing in its self.

What exactly is going on?

At least Gundersen is making a statement based on what information he has and standing by it,bias or no bias.

I know nothing about nukes. I read this complex lost power hence the ability to move water and these things happened after a 9.0+ quake and 45'+ ocean surge which ruined and/or disabled any functional mechanical equipment on site.

At this point in time, not counting the venting of radioactive materials, explosions, leakage, damaged and exposed nuclear material to the fresh air and corresponding fallout which is so bad that in some areas of ground zero you can't even stand there more than 10 minutes to work let alone people kicked out of their housing miles from the site... most of us are waiting for what is left of the 3 nuclear cores and 4 spent fuel ponds to cool enough to start serious mitigation of the aforementioned conditions. Seems only unit 3 is not cooperating properly with cooling down completely at this time.

Some professionals can't agree on readings so there is some unknowns in play, at least in the publicly released information. Which is understandable because some conditions being encountered were never envisioned, times 4.

BTW, there is on going contamination and pollution as you read this due to the large amounts of water needed to cool the hot spots that shouldn't be reused and is lost as steam and in runoff to the sea anyway.

 

[robinson]

My questions about robotics is speaking to the point of radiation damage to electronics. If it was just alpha and beta robots could easily be sent in and around with cameras, to at least get a look at what is or isn't there.

Both gamma radiation and neutron radiation disrupt circuits, but as somebody noted, just seeing where the radiation knocks a small robot out would still be a source of information.

 

[razzz]

I_P says: Wiki summarizes the public statements and conjectures from official sources...

I said reference. It's certainly not a case study. Since anyone and their mother can submit to Wiki or bias can change the informational writeup at Wiki, yes, you do have to take the site with a grain of salt (it has always been a drawback with Wiki due to potential scrubbing of facts by entities with agendas)

Cites abound in the footnotes.

Wiki is fluid, I was checking the chart concerning fuel 'assemblies' on-site, left and came back to find 'new fuel assemblies' column added to the chart. As I read it, doesn't add to the totals just tells you how many of the newer (potent/longer life) fuel assemblies are present.

 

[AntonL]

Thanks again to tsustuji @post # 2680 for the IR images provided
https://www.physicsforums.com/showpost.php?p=3227707&postcount=2680

Yes, I am sure tsustuji san is interested in a bit more what Tepco and his government tell him.

There are more, I combined the history in three pdf files

when analysing, please be careful of reflected heat by the sun and on some images one can see the shadows of the buildings in the morning sun

To translate just select Japanese text and paste into translate.google.com

on more file for the 20th in the next post

 

[AntonL]

in continuation thermal image for the 20th march

 

[shogun338]

Is the fuel crane normally located in the top floor of the Unit ? In Unit 4 pics it is sitting on floor of second floor of blow out from top . Would this position be the bottom of spent fuel pool ?

 

[AntonL]

ADDENDUM:
Correction of initial error of interpretation on my part - the "ground activity is not from heat sources on the ground. There is a perspective error. The heat sources labeled "ground activity are from lower levels of the building. Also, remember, these images are in the IR spectrum, presumably, not the X-ray or gamma ray spectrum.

Look at attached image - you can see the shadow of the morning sun, so ground activity are sun reflecting of the side walls and other objects on the ground. this image from 30 march

 

[shogun338]

NEW THERMAL IMAGE ANALYSIS, UNIT 4

Thanks for the new images, tsutsuji @ post # 2680

https://www.physicsforums.com/showpost.php?p=3227707&postcount=2680

Here are new thermal images (at least to me) of Bldg. 4. I presume the "hot" area to the right of the SFP is the open core of the reactor with residual radioactivity, and I hope this is normal.

Without,

http://i306.photobucket.com/albums/nn270/tcups/Picture41.png

and with my annotations.

http://i306.photobucket.com/albums/nn270/tcups/Picture42.png

ADDENDUM:
Correction of initial error of interpretation on my part - the "ground activity is not from heat sources on the ground. There is a perspective error. The heat sources labeled "ground activity are from lower levels of the building. Also, remember, these images are in the IR spectrum, presumably, not the X-ray or gamma ray spectrum.

{open core of the reactor with residual radioactivity, and I hope this is normal.} I think the heat seen here is from fuel rods that where reported to have been blown out during explosion at Unit 4 . They reported that fuel rods where scattered in Unit 4.

 

[shogun338]

Look at attached image - you can see the shadow of the morning sun, so ground activity are sun reflecting of the side walls and other objects on the ground. this image from 30 march

Ground heat will not show like that on a thermal camera . There is something there more than normal ground heat . They have reported that fuel rods in Unit 4 where scattered during explosion .

 

[AntonL]

Ground heat will not show like that on a thermal camera . There is something there more than normal ground heat . They have reported that fuel rods in Unit 4 where scattered during explosion .

Browse through the the pdf files in https://www.physicsforums.com/showpost.php?p=3228130&postcount=2716" and you will see exactly areas that are illuminated by the sun and areas in shadows and on cloudy days these areas are absent.

However, I agree to you there are heat sources on the roof of unit 4 that do not tie in with the SFP

 

[shogun338]

Look at attached image - you can see the shadow of the morning sun, so ground activity are sun reflecting of the side walls and other objects on the ground. this image from 30 march

Upper arrow is pointing to where a gray mass was in a pic I posted . Showing a lot of heat there .

 

[AntonL]

This image of 29th March shows clearly area illuminated by sun, the shaddow unit 4 casts

But the the roof of unit4 has heat outside the SPF

 

[TCups]

{open core of the reactor with residual radioactivity, and I hope this is normal.} I think the heat seen here is from fuel rods that where reported to have been blown out during explosion at Unit 4 . They reported that fuel rods where scattered in Unit 4.

Can you cite the source of the report of fuel rods scattered in unit 4, please. Thanks.

 

[razzz]

If Unit 3's massive explosion didn't weaken Unit 4 then Unit 4 must have been so preloaded with hydrogen that when it did explode it ballooned the roof and pulled the four corners inward (at least two of them). The panels blew out like designed but the super structure was forced up and inward.

 

[orndorf]

May i ask what exactly it is we can ascertain from these IR images?

 

[I_P]

Re the damage of #4 and the piece of debris stuck into the roof:

Its part of the roof of Unit 4 that fell back down after explosion .​

Thanks, it makes sense. Presumably the roof was a concrete or tarmac sheet laid on top of the metal framework, that was lifted off by the explosion without damaging the latter.

But now that the "shot by reactor #3" theory is busted, I am left wondering at puzzling features of the damage on #4:

1. The concrete walls of the upper floor, on the West and East sides, seem to have been pushed INWARDS against the concrete columns.
2. The same concrete shell on the North side (facing #3) was peeled off the concrete columns but kept hanging from the top.
3. The top edge of the North wall was bent INWARDS, whike the first horizontal concrete beam just below it was bent outwards.
4. While that beam was damaged, the much weaker outre shell remained mostly in place.

Could go on, buy you get the idea.

Perhaps there was an explosion BELOW the topmost floor, and that created overpressure on the OUTSIDE of the walls of the top floor, pushing them in?

Unit 3 exploded on March 14th, 11:15am. There was an explosion at unit 4 on March 15th, ~6:00am that blew out two wall panels. This damage was shown in helicopter flyovers. There were attempts to spray water into the pool at this time I believe and two instances of fire were noted. Some time after this there must have been at least one more (larger) explosion to leave the building in it's current state. You can see blast driven debris trails and damage that exited from both units 3 (very obvious) and 4 (less obvious) in the hi-res aerial photos.

 

[jensjakob]

I have plotted the data from the NISA/METI press relases:

http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html

Hope it helps. All the best, --stolfi

Great stuff - thank you very much.

What I wonder about, is that drywell is pretty radiating in all 3, and in #1 the Torus is also quite hot.

Why is the Torus so active in #1 but not in #2 and #3?

 

[|Fred]

Fred:
https://www.physicsforums.com/attachment.php?attachmentid=33968&d=1301856201
Are you seeing a picture of a green overhead crane I have overlooked? If so can you reference the photo? Thanks.

look at the top center of the picture , you'll see the big top dark green crane,

 

[Emreth]

I want to clarify something with the IR images, although some might seem to show ground activity, that's mostly due to the variation in the measured temperature range, when the same color spectrum is used (rainbow in this case). So in one picture, green might correspond to 15deg, but in another to 30deg. Keeping that in mind, I don't see anything anomalous on the ground apart from slightly shiny objects (in the IR range). Another point is, because there is steam over the SFP's, the temperature readings will be affected (show lower values).

 

[Jorge Stolfi]

Photos of the infamous "leak in the pit" from the METI press release 71 (2011-04-03-15:30) :http://www.meti.go.jp/press/2011/04/20110403002/20110403002-4.pdf"

 

[razzz]

This http://www.whas11.com/home/Hopes-new-power-line-may-ease-Japan-nuclear-crisis-118105609.html" has the US claiming Unit 4 pool is dry. Company says no. This post has a slightly different picture of Unit 4 with no steam showing at all after the blast with the poster's own speculations.

 

[AntonL]

This http://www.whas11.com/home/Hopes-new-power-line-may-ease-Japan-nuclear-crisis-118105609.html" has the US claiming Unit 4 pool is dry. Company says no. This post has a slightly different picture of Unit 4 with no steam showing at all after the blast with the poster's own speculations.

That is from 16 march - nearly 3 weeks old!

 

[razzz]

May i ask what exactly it is we can ascertain from these IR images?

Extreme heat radiating from that particular area that only nuclear decay could cause. Hopefully the area is surrounded by water as it cools down.

 

[Jorge Stolfi]

Unit 3 exploded on March 14th, 11:15am. There was an explosion at unit 4 on March 15th, ~6:00am that blew out two wall panels. This damage was shown in helicopter flyovers.

Do you mean the two central panels on the North and South walls (3rd row from top)? Then the explosion was below the upper floor, right?

Or perhaps you mean two panels on the South wall, near the SE corner? (That is where the Green Machine can be seen, and some reports claim that the SFP is just below it.)

Some time after this there must have been at least one more (larger) explosion to leave the building in it's current state.

That is interesting. I haven't seen anyone mention a second explosion at #4.

 

[ohohohoh]

For reference, Wikipedia has a decent time lines and overall information combined together.

http://en.wikipedia.org/wiki/Fukushima_I_nuclear_accidents"

...

I looking for more details for the first hours and days.
When did the diesel generators fail? When did the batteries run out of power? When stopped the emergency cooling for each unit? When exactly did they start venting? etc. etc.

Some of that information (eg. about the diesel generators) is in the Japanese Wiki (try to translate by google)
http://ja.wikipedia.org/wiki/%E7%A6%8F%E5%B3%B6%E7%AC%AC%E4%B8%80%E5%8E%9F%E5%AD%90%E5%8A%9B%E7%99%BA%E9%9B%BB%E6%89%80%E4%BA%8B%E6%95%85%E3%81%AE%E7%B5%8C%E7%B7%AF"




Other information is still missing (batteries).

For me it is not clear what happened, especially whether the engineers always did the right things at the right times.

 

[razzz]

That is from 16 march - nearly 3 weeks old!

I know that but the question is, who do you believe? Pools are dry and an explosion spreads fuel everywhere or fuel partially exposed with 'normal' hydrogen explosion.

It was a no win either way for if the pool was empty for any length of time and refilled by chopper or hose, then they had to create a blast by adding water on hot fuel rods. Low water in the pool, smaller explosion happens anyway.

 

[|Fred]

Thank you for the IR image btw , we now have evidence that the concrete slab on unit 3 is gone

 

[razzz]

I looking for more details for the first hours and days.
When did the diesel generators fail? When did the batteries run out of power? When stopped the emergency cooling for each unit? When exactly did they start venting? etc. etc.

Other information is still missing (batteries).

For me it is not clear what happened, especially whether the engineers always did the right things at the right times.

Browse thishttp://www.docstoc.com/docs/7522336...m=email&utm_campaign=109121477&utm_content=3"

 

[I_P]

Do you mean the two central panels on the North and South walls (3rd row from top)? Then the explosion was below the upper floor, right?

Or perhaps you mean two panels on the South wall, near the SE corner? (That is where the Green Machine can be seen, and some reports claim that the SFP is just below it.)



That is interesting. I haven't seen anyone mention a second explosion at #4.

I believe it was the SE corner by the pool (first explosion). I have never seen documentation of other explosions - except the unmistakable evidence in the current aerial photos. I find this puzzling. It must have occurred at night, but the onsite workers must have heard it. Like the spike in offsite radiation on the 21st - clear evidence of serious change but no official explanation or mention. Adds to the sense that much more is known and suspected than has been publicly discussed.

 

[PietKuip]

"Tellurium 129 Presence Is Proof Of Inadvertent Recriticality At Fukushima"

That's the latest claim from Gunderson, via http://www.zerohedge.com/article/tellurium-129-presence-proof-inadvertent-recriticality-fukushima"

It has a 70 minute half life. Data collected 30.03.11

http://www.tepco.co.jp/en/press/corp-com/release/11033110-e.html

There is also a metastable isomer of this isotope, see http://nucleardata.nuclear.lu.se/nucleardata/toi/nuclide.asp?iZA=520429

It has a half-life of 33.6 days, and most of it (63 %) decays to the ground state by emitting a gamma. So the ground state is expected to be in the spectra. In steady state ("equilibrium"), it should be in the data with 63 % of the activity of the metastable isomer.

Its presence does not prove any recent criticality. It does not even point to recent criticality.

 

[Cire]

Does anyone know where the vent from the drywell into upper containment should be? Or the vent for the wetwell? Could these vents which I understand fail open be the source of the steam.

I also wonder why the water pouring into the ocean via the crack isn't steaming hot. If the feed water temperatures are correct the water temperature exiting that crack should be close to boiling. Large amounts of water vapor should be visible especially with the low ambient temperatures.. I don't see it. I see relatively cold water being injected into the channel.

I think the drywell and wetwell are completely flooded in reactor 2 except for an ullage space and at a lower temperature then the sensors are reporting. Steam in an intact reactor vessel is venting into the wetwell and the water level is balanced by the steam pressure and the water injection pressure. Steam is going up the vent and colder injected water is exiting another path.

 

[Jorge Stolfi]

Updated plots of #Fukushima reactor temp, pressure, water level+rate, CAMS radiation to #NISA / #METI release 72 (apr/04 08:00):
http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html

 

[ivars]

TEPCO does not know where the contaminated water comes from:

http://www.saposjoint.net/Forum/viewtopic.php?f=66&t=2657&p=31585#p31585"

Tokyo Electric Power Co. used colored powder Monday to trace the source of highly radioactive water leaking into the sea near the troubled Fukushima Daiichi nuclear power plant, while mulling the use of silt-barriers in the sea to prevent the further spread of radiation.

The plant operator poured 13 kilograms of the powder into an underground trench to find the point from where radioactive water is leaking into the Pacific Ocean in front of the plant, after its attempt to block the leakage from a cracked seaside pit connected to the No. 2 reactor turbine building showed no effect so far.

Radioactive water has been filling up the basement of the No. 2 reactor turbine building and the tunnel-like trench connected to it. The powder was injected into the trench shortly after 7 a.m. but did not come out from the crack as of 11 a.m., according to the company officials.