Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[artax]

In this image there's an area labelled outlet intake, would it not be feasible to use this for some water storage? (after a little wall building)
If it's just TESCO workers running around with fire hoses and the like they're not going to achieve much are they.
They need the biggest pumps/helicopters/barges and tugs the planet can offer.
This is a world problem, and a big one...

 

[PietKuip]

These are two gamma spectra of air filters taken in Seattle collected on 17 and on 18 March.

See also http://www.npl.washington.edu/monitoring/

The paper concludes that isotope ratios indicate that the chain reaction had been stopped at the time of the earthquake.

 

[83729780]

An additional 1,500 tons of radioactive water will also be released from the No. 5 and No. 6 reactors, after runoff was found flooding parts of their turbine buildings. There are concerns that the water could damage the backup diesel generators for the reactors’ cooling systems, Mr. Edano said. Water from these reactors will be released 300 tons at a time over five days.

http://www.nytimes.com/2011/04/05/world/asia/05japan.html?_r=1&hp

runoff flooding the turbine buildings of 5 and 6? Implies that an entire swath parallel to the ocean is flooded. 5 and 6 are quite far from 1-4

[PLAIN]http://www.visa2tour.com/wp-content/uploads/2011/03/nuclear-power-plant-japan-satellite-images-damage-overal.jpg

 

[artax]

Anyone seen the analysis results of this moderately contaminated water they've discharged?

 

[WhoWee]

Yes - Cs and Iodine are volatile at fuel operating temperatures, and if the ceramic fuel gets hot enough, the Cs and I can come out into the gap between pellet and cladding. If the cladding is breached - i.e., cracks - then Cs and I can be carried out into the coolant. Xe and Kr obviously come out.

In normal operation, when fuel fails - cladding is breached - the coolant can enter the fuel rod. The UO2 oxidizes which reduces the thermal conductivity, which increases temperature, which causes Xe, Kr, Cs, I and some other volatile elements to migrate out of the cermamic. Oxidation of UO₂ also increases the diffusivity of some fission products - particularly noble gases.

So once can release Cs and I without melting the fuel.

Also - I beta decays to Xe, which beta decays to Cs, so Cs, in addition to being a direct fission product, is also a daughter product of Xe decay.

Is it possible at any point to blow a powdered alloy (or perhaps a multi-staged application) onto the damaged cladding that might coat and repair the damage - at least temporarily - then repeat the process?

 

[Jorge Stolfi]

First of where is the concrete slab ? Second how come is the crane on top of the reactor if the slab blew ?

Whether the lid is in place or not: The explosion on #3 blasted away the concrete columns on the N, S, and W sides of the building, but left the E columns mostly in place. The metal beams of the roof that were above the crane remained attached to the columns, and presumably so did the crane. Thus it is possible that the roof and crane were partially lifted by the explosion, pivoting on the W side, and then fell back to their original positions (except for the lack of support on the E side).

 

[wallu]

[PLAIN]http://i.min.us/imQ6vm.jpg[/QUOTE]

the original picture is shot with a weird angle...
I made it more clear here.

the steam come from the utilitypool or the fringe between the utility pool and the slab hole
http://i.min.us/imMhCM.jpg

No, I meant whole floor is gone where slub was. That red dot is actually pretty much on right hight for slab, but positioned too much west. If slab was at that photo, it would have to float in the air.

I see that whole floor around the reactor is gone. Very small part of it what's left is in my photo. Everything else is gone. Please look at it, if am I right. And also there is original floor level in chute corner.

Here is again where floor level is. Isn't it below two top most "squares"? Look at this photo where floor level should be. You can see same damaged wall of NE corner.
http://www.reuters.com/news/pictures/slideshow?articleId=USRTR2KAAL#a=27"
If there is no floor where concrete shield(or slab) should be, how can it be there? Point of my first post was that most upper part of containment is gone with floor.

In fact I think that hole is DW, not slub hole.

 

[Jorge Stolfi]

Very useful plots but data don't seem updated since Apr 02. And I think latest release from NISA is 70 (at least in English).

It shoud be updated now to release 72. Be sure to force reloading, the URL is the same so you may be seeing a cached copy.

 

[Jorge Stolfi]

Could someone please explain how TEPCO is measuring the temperatures, pressures, and CAMS readings?

AFAIK all electronic instruments are inoperative and no one can get close to the reactors. So I presume that they are measured through pipes or thermocouple wires that extend to some place outside the buildings. Is that the area where the fire extinguishing pipes begin?

 

[|Fred]

it is my understanding that gauges are and have been working in the control room (analog power?) as they had to go every now and then to check the value with torch light.. and now they have regular cellar light

 

[Astronuc]

Is it possible at any point to blow a powdered alloy (or perhaps a multi-staged application) onto the damaged cladding that might coat and repair the damage - at least temporarily - then repeat the process?

As far as I know, that would not work, partly because the fuel is supposed to be underwater, there is no way to ensure uniform or appropriate distribution, and there is no satisfactory binder.

They could conceivable dump a bunch of resin powder or beads in the pool. Normally, the coolant or condensate is 'polished' in a filter demineralizer that is a basically a huge filter with a resin coating - much like in principle a 'green sand' filter.

There are two groups of fuel to be concerned about, the fuel in the SFPs and the fuel in the core. If any fuel is damaged, it will be a radiological risk.

Reactor personnel have to deal with failed fuel on occasion (although there has been a program in place for over a decade to drive failure rates to zero). Normally, it's one or a few assemblies with typically 1 failed fuel rod. We maybe looking at 100s or thousands of failed rods, and that's very complicated from a radiological standpoint. If the tie rods are failed, then special tooling will be required to fish the damaged fuel out of the core. In fact, special baskets may be necessary in order to remove damaged fuel.

Hopefully, there are some fuel assemblies in the core which are intact - basically the low power assemblies at the periphery of the core, or the low burnup fuel.

I'd surely like to know the state of the fuel in the SFPs of Units 1-4, particularly unit 4. I suspect 4 has the most damaged fuel, and I'm not sure of the others.

 

[tsutsuji]

Discussing the black smoke at reactor 3 (probably that black smoke which was reported on 23 March), Kenichi Ohmae suspects the reactor pressure vessel is perforated : http://www.nikkeibp.co.jp/article/column/20110404/265766/?ST=business&P=2

 

[Bodge]

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.

Really looks like Gunderson should keep his gob shut.

If CL-38 detection was real then that would be the 'smoking gun'.

 

[michael200]

Cause of Fukushima Unit 4 damage

It is reported that the cause of the unit 4 building damage was a H2 explosion caused by overheating of the discharged fuel in the U4 spent fuel pool. To the best of my knowledge, there is no photgraphic evidence of the explosion. Something that has troubled me since the first pictures of the Unit 4 damage on 16March, was whether there actually was a loss of inventory in the U4 spent fuel pool. Attached is a markup of the first photograph that was released on 16 March showing the U4 buiding damage. One can find the photo on Reuters site. This photo was taken before any water injection/spray in Unit 4. Perhaps, I'm missing something, but it sure looks to me like there was still significant water in the fuel pool on March 16. Anyone have an alternative speculation?

 

[sp2]

http://www.nytimes.com/2011/04/05/world/asia/05japan.html?_r=1&hp

runoff flooding the turbine buildings of 5 and 6? Implies that an entire swath parallel to the ocean is flooded. 5 and 6 are quite far from 1-4

[PLAIN]http://www.visa2tour.com/wp-content/uploads/2011/03/nuclear-power-plant-japan-satellite-images-damage-overal.jpg[/QUOTE]


Don't forget, they did all get hit by a series of very large waves.

(I don't know if water in the basements of 5 and 6 necessarily came all the way over from runoff from 3 and 4.)

 

[TCups]

It is reported that the cause of the unit 4 building damage was a H2 explosion caused by overheating of the discharged fuel in the U4 spent fuel pool. To the best of my knowledge, there is no photgraphic evidence of the explosion. Something that has troubled me since the first pictures of the Unit 4 damage on 16March, was whether there actually was a loss of inventory in the U4 spent fuel pool. Attached is a markup of the first photograph that was released on 16 March showing the U4 buiding damage. One can find the photo on Reuters site. This photo was taken before any water injection/spray in Unit 4. Perhaps, I'm missing something, but it sure looks to me like there was still significant water in the fuel pool on March 16. Anyone have an alternative speculation?

@michael200

Compare your image to this:

http://i306.photobucket.com/albums/nn270/tcups/FHM.jpg

The "reflection" seems dubious. More likely, you are seeing more of the substructure below the operator's platform than a reflection.

 

[michael200]

Your picture is of a different refueling bridge design.

 

[MadderDoc]

Whether the lid is in place or not: The explosion on #3 blasted away the concrete columns on the N, S, and W sides of the building, but left the E columns mostly in place. The metal beams of the roof that were above the crane remained attached to the columns, and presumably so did the crane. Thus it is possible that the ro the crane remained attached to the columns, and presumably so did the crane. Thus it is possible thof and crane were partially lifted by the explosion, pivoting on the W side, and then fell back to their original positions (except for the lack of support on the E side).

However, from looking at

(at time stamps about 10:13:27, and about 10:20:28)
those beams and with them the crane do indeed seem to have fallen flat on the floor -- smack on top of the lid, and with steam gushing out from under it.

 

[TCups]

Your picture is of a different refueling bridge design.

Your reflection is equivocal at best.

 

[TCups]

However, from looking at

(at time stamps about 10:13:27, and about 10:20:28)
those beams and with them the crane do indeed seem to have fallen flat on the floor -- smack on top of the lid, and with steam gushing out from under it.

Look back carefully at the debris on the ground at west side of Bldg 3 and you will see why the crane fell.

 

[NUCENG]

Did I hear that the two fatalities were in the basement of Bldg 4 -- I can't remember for sure? If they were working in the basement of Bldg 4, then were they perhaps trying to do just that when the explosion occurred?

Press Release (Apr 03,2011)
Employees of TEPCO Who Were Missing at Fukushima Daiichi Nuclear Power Station


Due to the Tohoku-Taiheiyou-Oki Earthquake which occurred on March 11th
2011, two TEPCO employees, who had been working at the turbine building
of Unit 4 for site investigation, went missing.
We had put all our strengths to search them, and approximately at 3:25 pm
and at 3:53 pm, today, March 30th, 2011, those employees were found at
the basement of the turbine building and we confirmed their death
yesterday.
We would like to offer our deep regret that our workers died while
working at the plant and heartfelt condolences to the bereaved families.

[Deceased Employees of TEPCO]

Kazuhiko Kokubo (Age: 24) Operation Management Department One, Fukushima
Daiichi Nuclear Power Station
Yoshiki Terashima (Age: 21) Operation Management Department One,
Fukushima Daiichi Nuclear Power Station

 

[WhoWee]

[Deceased Employees of TEPCO]

Kazuhiko Kokubo (Age: 24) Operation Management Department One, Fukushima
Daiichi Nuclear Power Station
Yoshiki Terashima (Age: 21) Operation Management Department One,
Fukushima Daiichi Nuclear Power Station

I'm quite surprised by the ages (24 and 21) of the deceased workers.

 

[TedNugget]

Pure speculation:

Ages 24 and 21 sound like workers who were sent to do something even though there was a Tsunami Alert.
Their listing in the press release just includes their names and division, no titles but could operation Management mean they were in a higher pay grade?
If not, that would mean (a) supervisor(s) still living with guilt.

That they were in Turbine 4, which one would assume everyone on site knew reactor 4 was down, could indicate the caution they had relating to the spent fuel pool. (With the Turbine buildings holding condensers and providing cooling for both the reactor and SFP).
The workers were found in a basement - auxiliary control room as I recall.

 

[AntonL]

I have managed to identify the shared pool No. 7 for very old fuel
one of the thermal images had it labelled in Japanese

It is west of reactor No. 4

 

[MadderDoc]

..Perhaps, I'm missing something, but it sure looks to me like there was still significant water in the fuel pool on March 16. Anyone have an alternative speculation?

I'll think about that. Looking down in the unit 4 sfp with the more recent crane camera there just appears me to be 'something dark' down there -- judging from the railings seen on the far side of the pool, that surface is several meters below floor level --, and it does not look like water. (Alas, seeing steam obviously does continually escape from the pit, there must be some water down there, still

 

[Jorge Stolfi]

it is my understanding that gauges are and have been working in the control room (analog power?) as they had to go every now and then to check the value with torch light.. and now they have regular cellar light

Well, the temperature and pressure data were available since shortly after the accident (at least for some units), well before they brought electricity to the control room. And, AFAIK, the control room panel is still dead.

 

[M. Bachmeier]

Really looks like Gunderson should keep his gob shut.

If CL-38 detection was real then that would be the 'smoking gun'.

When CL-38 was first (reported) found it had a lot of people concerned, but it also had them scratching their heads because other isotopes were missing re: Astronuc and a student of radio chemistry.

The point here is simple. Gunderson should have been checking for reasons to dismiss his hypothesis (good science). And A Google search would have led him here, where questions about the reliability of the reported measures were raised at least two or three days before he made his public proclamations. Astronuc's responses to my and others questions have been frank (if a little scary at times), but showed no indications of bias.

I'd take Astronuc's opinion of event over Gunderson any day.

 

[|Fred]

However, from looking at

nice video
the slab does have a strair like edge
[PLAIN]http://k.min.us/ik5km0.jpg
and the is a similarity with the structure that we see there but is it ?
[PLAIN]http://k.min.us/imQyfs.jpg

 

[M. Bachmeier]

It is reported that the cause of the unit 4 building damage was a H2 explosion caused by overheating of the discharged fuel in the U4 spent fuel pool. To the best of my knowledge, there is no photgraphic evidence of the explosion. Something that has troubled me since the first pictures of the Unit 4 damage on 16March, was whether there actually was a loss of inventory in the U4 spent fuel pool. Attached is a markup of the first photograph that was released on 16 March showing the U4 buiding damage. One can find the photo on Reuters site. This photo was taken before any water injection/spray in Unit 4. Perhaps, I'm missing something, but it sure looks to me like there was still significant water in the fuel pool on March 16. Anyone have an alternative speculation?

One explanation that was and is being looked at is some kind of enhanced explosion. Take your pick from damaged fuel to other gas released due to earthquake damage.

 

[|Fred]

judging from the railings seen on the far side of the pool,

not railing but the other crane