Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[Giordano]

hello. i can't give you any hard numbers, but Robert Peter Gale who coordinated the medical relief efforts for victims of the Chernobyl disaster and who is in J-Village, where all the international experts in fukushima berate, writes in german spiegel magazine that so far in fukushima 10% of the chernobyl-amount of iodine-131 and caesium-137 have leaked.
he also writes that he doesn't expect many deaths from this and that smoking is more dangerous for manchild than this etc. though.
forgive my bad english, i often get probs with the syntax when building too long sentences.

Thank you for your answer.

Interesting and somewhat comforting figures.

Have you seen this:
http://www.zamg.ac.at/docs/aktuell/Japan2011-03-22_1500_E.pdf

 

[Giordano]

Sorry, I may not be able to update my plots of Fukushima Daiichi vars until next tuesday.
(However the scripts and files are availabe at the site, if anyone cares...)
http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/

I think your plots are great. And I will wait patiently for your updates.

(I have actually been in Campinas once and walked around the lake.)

 

[MJRacer]

Sirius

From: http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html
Unit 3 on 3/14 at 9:00 AM:
Core: 409 kPa
D/W: 490 kPa
torus: 475 kPa

 

[cola]

Thank you for your answer.

Interesting and somewhat comforting figures.

Have you seen this:
http://www.zamg.ac.at/docs/aktuell/Japan2011-03-22_1500_E.pdf

thanks.sounds interesting and seems to be much more than stated by that guy who wrote the article i mentioned.the article( http://www.spiegel.de/spiegel/0,1518,754931,00.html ) he wrote in the german magazin was titled 'german angst' (german fear) and was generally saying it wasnt all so bad.if that is the trend in their camp there...
enough of my no numbers games :p

 

[Sirius (b)]

Sirius

From: http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html
Unit 3 on 3/14 at 9:00 AM:
Core: 409 kPa
D/W: 490 kPa
torus: 475 kPa

Thanks, is that above the designed limit for this Mk I type of BWR reactors? A sudden increase in pressure could render events observed.

Pressure readings in both RPV and dry well at 1 atm tells you the story, that I've told you before. :)

Must read new report from Areva dated April 7th - http://www.fairewinds.com/sites/default/files/AREVA%20Fukushima.pdf I haven't started yet, but if it's anything like the one from 26th, it will be good. (apart from the fact that they've explained Unit 1 and applied the same theories both to 2 & 3), here it is - http://www.megaupload.com/?d=OJS80EGJ

 

[elektrownik]

This is Japanese but it is always updated before english version, you can translate it with google, but even without translation data are in tables and on drawings so it is easy to understand: http://www.nisa.meti.go.jp/itiran/new_genshi_index.html

 

[PietKuip]

NHK has found some Tepco data from the day of the quake. In unit 1, the water level sank to 45 cm over the fuel rods. If I remember correctly, that was 7 hours after the quake.

The pressure in the pressure vessel went down, and the pressure in the containment vessel had gone up. NHK says this suggests that pressure vessel had become leaky because of earthquake damage (not tsunami induced).

 

[clancy688]

About Mr. Gale:
Most germans are very, very frightened of nuclear power. I don't think there's any other country in the world which can top our hysterical reaction to the Fukushima accidents. Not even Japan. And not even close.
So Mr. Gales report was "not received well" (understatement of the century), because in most german minds, he's downplaying the accident massively.
But if even he states, that Jod-131 and Cesium-137 emissions are at 10% of Tchernobyl, then there must be significant radiation spreads. (Btw, "only 10% Tchernobyl" my ***... is he kidding? If Fukushima is at 10% Tchernobyl, Japan is in deep **** now...)

Have you seen this:
http://www.zamg.ac.at/docs/aktuell/Japan2011-03-22_1500_E.pdf

That's a very old estimate of the radiation release. ZAMG has updated its expectations frequently, the latest one being only a few days old (2nd April). But it's not available in english:
http://www.zamg.ac.at/aktuell/index.php?seite=1&artikel=ZAMG_2011-04-02GMT09:28

I will translate:

Airborne emission estimate of Jod-131 and Cesium-137 during the first week:

March 14th:
Jod-131 10^16 to 10^17 Bq/day
Cesium-137 10^15 to 10^16 Bq/day

March 12th-13th, 15th-19th:
Jod-131 10^14 bis 10^17 Bq/day
Cesium-137 10^13 to 10^16 Bq/dayConclusion:
Between 10^16 and 7 * 10^17 Bq Jod-131 and between 10^15 and 7 * 10^16 Bq Cesium-137 have been released during the first week. There's another estimate by IRSN:
http://www.irsn.fr/FR/Actualites_presse/Actualites/Documents/NI-terme-source-22032011-tableau.pdf

9 * 10^16 Bq Jod-131 and 10^16 Cesium-137 between March 12th and 22th.

But those are ONLY airborne emissions.

 

[|Fred]

...

This actually is almost to the letter the romance imagined by a French journalist with a PhD in Nuclear Physic about three weeks ago, I'm surprise that it's still considered as it was obvious that it was a non sens, even three weeks ago.

Would you be kind enough to point out the 8m S/N Hole around the floor where the fuel assemblies are stored ?

 

[MJRacer]

Same source states 400 kPa is maximum D/W pressure.

 

[Sirius (b)]

This actually is almost to the letter the romance imagined by a French journalist with a PhD in Nuclear Physic about three weeks ago, I'm surprise that it's still considered as it was obvious that it was a non sens, even three weeks ago.

Would you be kind enough to point out the 8m S/N Hole around the floor where the fuel assemblies are stored ?

Is trolling allowed on this forum?

Facing South,

Facing NE,

[PLAIN]http://img.ibtimes.com/www/data/images/full/2011/03/23/77344-efforts-to-spray-water-into-the-no-4-reactor-at-the-fukushima-daiichi-.jpg

On topic: In the Areva report you have 7 hours in Reactors 2 & 3 without water, 27 hrs for Unit 1 - temperatures reaching melting points of both zircalloy and uranium oxide, then you have explosions in Units 1 & 3, which differ and then you get to page 25, and I quote, "Its not Chernobyl-like."

Same source states 400 kPa is maximum D/W pressure.

4-5 bar measured, I quote from the April 7th Areva presentation,

Containment
 Last barrier between Fission
Products and Environment
 Wall thickness ~3cm
 Design Pressure 4-5bar

Actual pressure up to 8 bars
 Normal inert gas filling (Nitrogen)
 Hydrogen from core oxidation
 Boiling condensation chamber
(like a pressure cooker)

 

[Giordano]

About Mr. Gale:
Most germans are very, very frightened of nuclear power. I don't think there's any other country in the world which can top our hysterical reaction to the Fukushima accidents. Not even Japan. And not even close.
So Mr. Gales report was "not received well" (understatement of the century), because in most german minds, he's downplaying the accident massively.
But if even he states, that Jod-131 and Cesium-137 emissions are at 10% of Tchernobyl, then there must be significant radiation spreads. (Btw, "only 10% Tchernobyl" my ***... is he kidding? If Fukushima is at 10% Tchernobyl, Japan is in deep **** now...)
That's a very old estimate of the radiation release. ZAMG has updated its expectations frequently, the latest one being only a few days old (2nd April). But it's not available in english:
http://www.zamg.ac.at/aktuell/index.php?seite=1&artikel=ZAMG_2011-04-02GMT09:28

I will translate:

Airborne emission estimate of Jod-131 and Cesium-137 during the first week:

March 14th:
Jod-131 10^16 to 10^17 Bq/day
Cesium-137 10^15 to 10^16 Bq/day

March 12th-13th, 15th-19th:
Jod-131 10^14 bis 10^17 Bq/day
Cesium-137 10^13 to 10^16 Bq/dayConclusion:
Between 10^16 and 7 * 10^17 Bq Jod-131 and between 10^15 and 7 * 10^16 Bq Cesium-137 have been released during the first week. There's another estimate by IRSN:
http://www.irsn.fr/FR/Actualites_presse/Actualites/Documents/NI-terme-source-22032011-tableau.pdf

9 * 10^16 Bq Jod-131 and 10^16 Cesium-137 between March 12th and 22th.

But those are ONLY airborne emissions.

Thank you for the updated estimates. ZAMG:s upper boundary is still less than the total Chernobyl emissions of the same isotopes (from the great source of Wikipedia).

Yes, I know, I haven't seen any total estimations of emission of any nuclide directly to the sea. That is one of the reasons I myself dared the task.

 

[|Fred]

Most germans are very, very frightened of nuclear power.

Never understood why nuclear energy (atom as they call it) has always been an issue in Germany...20 years ago when I was going in Germany they were blaming the French Nuclear Power at the border for the acid rain ..
That of course had nothing to do with the SO2 coming from the 520 million tons of coal burning in the german powerplants... But I'm getting off topic

 

[MadderDoc]

4 is pointing to the rail that surrounds the spent fuel pool . The smaller rods could be older spent fuel rods that have cooled for years so not to hot . The large grey mass looks like something that has melted . The FHM is has collapsed on top of spent fuel pool and crushed some of the railing around the spent fuel pool .

By comparing the photo below, and photos of the battered building, the FHM of unit 4 does not appear to me to have fallen off its support, rather it appears to be parked and in the correct position well above the spent fuel pool.

[PLAIN]http://www.gyldengrisgaard.dk/20020924_daiichi04/daiichi-04a.jpg

 

[|Fred]

Is trolling allowed on this forum?
Facing South,
Facing NE,

It is my opinion that Dominique Leglu wrote multiple papers with the utmost disrespect for the evidences available at the time. Further more I'm merely expecting that people coming with affirmation would have check if they had been discuss or dismissed before on this thread and if so present new evidences allowing reanalysis for everyone.

As far as the hole is concerned, I'm not convinced it is fuel assemblies are stored, it's definitively not where the Pool or the shaft are. It could be where the isolation condenser are if they did not change to many thing in the design of the unit 4 but it makes no real sens for those condenser to blow since the reactor was in inspection

 

[Sirius (b)]

Find the blueprint original by GE for this Mk., on the Section B-B, West facing you see that the SFP is in the S-SE corner of the containment buildings. The Southerly hole corresponds to the exact location of SNF assemblies, and it's confirmed via both: footage and thermal imagery.

I don't like waking up to reactors blowing up, but Good Night, all

P.S. Bah, here's the bp:

http://img291.imageshack.us/img291/1236/fukunitbwr1920.th.jpg
http://img23.imageshack.us/img23/9085/fukunitbwr3024f.jpg - (5,024 x 3,547) 2 MB
10 MB (9,889 x 6,984 pixels) - http://www.megaupload.com/?d=H0MPDIEP

 

[razzz]

I agree it is speculative and an error by orders magnitude is possible.

I was trying to get some numbers to the quite common statement that it is better to pollute the sea rather than the atmosphere/land.

Assume the worst then add your numbers with Tokyo Electric numbers then divide by 2, that should be close enough to the truth. [Edit: I see no reason not to figure a continuous steady flow of contamination into the, atmosphere, lithosphere and hydrosphere except when accelerated by the occasional explosion, unless someone can prove different]

Units 1&3 and pond 4 spewed a lot of their nuke material airborne so you can figure those are less than unit 2. Pond 2 might be an unknown.

The scientists are looking for hard numbers to base-on unless you work for Tokyo Electric, then all 'this' never happened. It must have been their worst nightmare finally to succumb to conditions for outside help, whereby having to release all their known figures to scientific circles. (I doubt the US was surprised by the numbers even though they try to downplay it at times)

Some say polluting the Pacific is less hassle due to its vastness or it's already a cesspool, I'm never quite sure which one they are relying on. Polluting the atmosphere works only at loftier levels and even then background benchmarks are raised.

Like changing exposure time to contamination, instead of a yearly dose limit, once in a lifetime higher exposure limit will be used. Difference is, you can't ever be exposed again after attaining the lifetime limit, technically but mainly to get the 'cleanup' workers in and out safely. Lots of them until the robots show up.

 

[shogun338]

Total activity levels of 70,000 - 80,000 Bq/kg were found in spinach leaves from one garden, while levels of roughly 9,000 Bq/kg were found in cabbage from another. Based on the Japanese Ministry of Science (MEXT) reports, 20-30% of this radioactivity is caused by cesium-137, which is far above the Japanese government limit of 500 Bq/kg for vegetables. The limit for iodine-131 it is 2,000 Bq/kg. http://www.panorientnews.com/en/news.php?k=910

 

[ceebs]

http://www.yomiuri.co.jp/dy/national/T110407005117.htm"

Tokyo Electric Power Co. is considering alternative methods, including the construction of improvised systems, to cool reactors at the crippled Fukushima No. 1 nuclear power plant.

Ongoing operations--which involve pouring water directly into the reactor cores to lower temperatures inside the pressure vessels of the Nos. 1 to 3 reactors to below 100 C--have not worked as expected, and restoration of the reactors' existing cooling systems is not likely to happen soon.

The discouraging outlook has prompted TEPCO to begin exploring new options.

 

[|Fred]

Find the blueprint original by GE for this Mk., on the Section B-B, West facing you see that the SFP is in the S-SE corner of the containment buildings. The Southerly hole corresponds to the exact location of SNF assemblies, and it's confirmed via both: footage and thermal imagery.

I'm familiar with those print (I actually posted them on this board), and although I'm not confident that are fully accurate for the 4th unit, for argument sake I will and I had gladly work with.. Still I'm not able to grasp your observation/affirmation. Could you please point out on those print your hole and how it is the location of Spent Nuclear Fuel.

To my best knowledge thermal imagine totally infirm your assessment , do does the blue print.. I could be mistaken after three weeks of intense home made forensic, on could lost his eye.

 

[Emreth]

Racer,

The height of the gas vent towers is 130 metres. There 3 are distinct pieces of debris seen emerging from the vertical dust cloud, they could be either: FHM, PCV dome, concrete DW plug, reactor lid itself. The SFP is not the cause of the explosion, there may have been hydrogen in the secondary containment (reactor room), but the trigger was the thermal explosion inside the RPV - cold water coming into contact with 3/4 melted core, which, possibly fell down to the bottom of the RPV, triggering the steam release via the most likely route - bolted top. While the torus may have been destroyed in the event, I would worry about fuel from the core and SFP of Unit 3.

Concrete was pulverised in the detonation, that is steel debris flying sky-high to 500 metres+, with the cloud reaching up-to 1 km, or more.

P.S. What pressure was reported for Unit 3 D/W, RPV prior to the explosion? The core had already melted to some percentage before then, otherwise you can't have the observed events.


Yes. Whatever was the cause of the damages seen to Unit 4 building, it blew a hole 8 metres in diameter South to North through it, around the level the fuel assemblies would be stored at.

If anyone is interested in latest thermal imagery of the plant, PM me and I'll get them sourced and uploaded.

You are a new poster here and i understand you haven't gone over the thousands of posts. All the things you mention were discussed here a while ago and debunked basically.
Reactor 3: The big blast is not directly related to the destruction of the top parts of the reactor, there were images posted here that show it's still there, with a crane collapsed over it, and steam escaping from the connection chute between that and the SFP. Also notice that the truss structure over the containment is intact unlike over the SFP. The thermal imagery, somehow surprisingly paints a rather rosy picture, with nothing substantially warm. A lot of seemingly hot spots arise from changes in the range of the IR measurements, with debris lying around at essentially ambient temperature. There are hot spots (70degC) over the SFP and the leaking parts from the PCV but that's about it, the rest are more or less cooler than a human being (less than 36degC), if a person was there it would be glowing red.

 

[shogun338]

Water leaked out of spent fuel pools at the Onagawa nuclear plant in northeast Japan after a strong aftershock rocked the region late on Thursday, but there was no change in the radiation levels outside the plant, operator Tohoku Electric Power said on Friday. http://www.reuters.com/article/2011/04/08/japan-leak-idUSL3E7F80BF20110408

 

[shogun338]

The Nuclear Regulatory Commission speculated Wednesday that some of the core of the No. 2 reactor had flowed from its steel pressure vessel into the bottom of the containment structure. The theory implies more damage at the unit than previously believed. http://www.nytimes.com/2011/04/09/world/asia/09japan.html?_r=1

 

[shogun338]

Broken pieces of fuel rods have been found outside of Reactor No. 2, and are now being covered with bulldozers, he said. The pieces may be from rods in the spent-fuel pools that were flung out by hydrogen explosions. Looks like we where right about fuel rods blown out of spent fuel pools .

 

[Cire]

but the trigger was the thermal explosion inside the RPV - cold water coming into contact with 3/4 melted core, which, possibly fell down to the bottom of the RPV, triggering the steam release via the most likely route - bolted top. While the torus may have been destroyed in the event, I would worry about fuel from the core and SFP of Unit 3.

I don't believe this occurred. At the time of the explosion TEPCO was pumping in water using a fire engine. You don't overpressure a massive pressure vessel and not have a nylon fire hose still attached to the feed line not burst. If the RPV over-pressurized then every pipe, fitting, connection to the reactor with a lower pressure rating would have gone first, followed by the RPV assuming it didn't depressurize fast enough.

The RPV is approximately 6 inches thick. The pressures required to yield a 6 inch thick piece of steel even at elevated temperatures is huge. I understand the reactor has an operating pressure, but the failure pressure is much higher.

The failure mode of an over pressurized reactor with a corium slag at the bottom would be to fail the bottom of the RPV. This is the same failure mode you see when a water heater fails. It looks like this..



If that occurred with the reactor we'd be looking at the reactor vessel sitting somewhere outside of the building.

This is why you design the system to fail anywhere but the RPV.

 

[ohohohoh]

Is there any information, whether they installed the "direct torus vent system" in Fukushima (unit 1,2 3) or not?

For "direct torus vent system" look at: http://www.nirs.org/factsheets/bwrfact.htm

 

[NUCENG]

Is there any information, whether they installed the "direct torus vent system" in Fukushima (unit 1,2 3) or not?

For "direct torus vent system" look at: http://www.nirs.org/factsheets/bwrfact.htm

Just found this today.

 

[razzz]

Just found this today.

Put a leash on it so it can't go to far. Need to know where it is at all times.

 

[|Fred]

Is there any information, whether they installed the "direct torus vent system" in Fukushima (unit 1,2 3) or not?

If you are referring to the 1980's US mandatory Upgrade to Mark 1 design, I was stated on numerous occasion that Hitachi did implement those update on the Fukushima plant.

 

[|Fred]

Just found this today.

Yes that's the info that has been spread in the news from the past 2 days it was initiated (I believe) by a reuters Paper by Roberta Rampton and Ayesha Rascoe dated from the 6th http://uk.reuters.com/article/2011/04/06/uk-japan-markey-idUKTRE73540Y20110406

"(Reuters) - The core at Japan's Fukushima nuclear reactor has melted through the reactor pressure vessel, Democratic Congressman Edward Markey told a hearing on the nuclear disaster on Wednesday.

"I have been informed by the Nuclear Regulatory Commission that the core of Unit Two has gotten so hot that part of it has probably melted through the reactor pressure vessel," said Markey, a prominent nuclear critic in the House of Representatives.

The leaked email originate directly from congressman Edward Markey's Office via a few forwarded mail by Neubauer (personal investigation)

http://markey.house.gov/docs/4-6-11markey_e-mail_2_-nrc_question_regarding_fukushima_unit_2.pdf

http://markey.house.gov/docs/4-6-11.markey_e-mail_1_-_nrc_question_regarding_fukushima_unit_2.pdf

So we can hardly consider them as concurring evidence but rather direct sourcing of the reported information. The information being


Based on radiation readings in the drywell and the torus, the NRC staff speculates that part of the Unit 2 core may be out of the reactor pressure vessel and may be in the lower space of thedrywell. Lower radiation readings in the torus suggest that there is not core material in the torus.


Open to argumentation