Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[WhoWee]

For Unit 1, the METI/NISA-JNES presentation indicates injection of water through the fire extinguisher system and water sprayed by truck. It's not clear that is still the case, but perhaps they lost the cooling system in Unit 1.

In Unit 2, they are using a motor operated pump with water from the fire extinguishing system.

There could be leaking water over the floor or through any cracks that might have occurred in the SFP steel liner and concrete structure.

Has the required (replacement) flow rate of water been posted?

 

[artax]

I don't really get you are you saying they are or aren't roof structure south of u 3? I seen some, I also see deformation of the metallic roof structure on the north suggesting the infamous FHM did its do

Sorry wasn't very clear, should've said missing from roof, not 'no-where to be seen', ...so the south of the building is where the FHM was and it took these out on it's way up.

 

[TCups]

Hope someone can find the live Fukushima video of the current 7.4 quake and tsunami expected to hit about now.

 

[algis.j]

Hopefully everything that has to goes down is already; as a new 7.4 with tsunami warning struck the area :(

 

[bigmike]

new back to back 7.4 earthquakes near sendai

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.php"

hopefully fukushima isn't impacted further from this

 

[Krikkosnack]

Inside Fukushima Evacuation Zone

http://energheia.bambooz.info/index.php?option=com_content&view=article&id=156%3Ainside-fukushima-evacuation-zone&catid=60%3Avideo&Itemid=85&lang=it

Tetsuo Jimbo, founder of Video News Network, a TV broadcasting website, and a colleague ventured into the area on Sunday. Before setting out, Mr. Jimbo consulted a radiation expert, who advised he spend a maximum of two hours in the zone. The 49-year-old journalist stayed for two and a half. A face mask -- the kind worn to fend off hay fever -- was his only protective gear. He admits he and his colleague got "kind of scared" when a host of large dump trucks drove by and the drivers were covered in what looked like "full radiation-proof suits" and gas masks.

 

[WhoWee]

Tetsuo Jimbo, founder of Video News Network, a TV broadcasting website, and a colleague ventured into the area on Sunday. Before setting out, Mr. Jimbo consulted a radiation expert, who advised he spend a maximum of two hours in the zone. The 49-year-old journalist stayed for two and a half. A face mask -- the kind worn to fend off hay fever -- was his only protective gear. He admits he and his colleague got "kind of scared" when a host of large dump trucks drove by and the drivers were covered in what looked like "full radiation-proof suits" and gas masks.

He should be "kind of scared".

 

[Astronuc]

Has the required (replacement) flow rate of water been posted?

Not that I'm aware of.


Regarding the Mag 7.1 (revised down from 7.4) which just happened of the coast near Sendai, there is concern about additional damage to FK units.

 

[rasherz]

TEPCO has stated that there has been no additional damage, sorry no link, it was just on Japanese TV. Still waiting to see if there is a tsunami though.

 

[jensjakob]

<sarcasm>Wouldnt TEPCO report that?</sarcasm>

Seriously - TEPCO has no possible way to state anything about the effect of the quake, since they don't have access to large parts of the plant due to radiation.

They can claim "Not identified any immediate damage in the areas that we can monitor".

But it is not valid to say "no additional damage", sorry

 

[StrangeBeauty]

USGS has it as a 7.1 so far (this can change as they get more data)
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc0002ksa.php

Depth was 30 mi. which is deeper than the 9.0 quake (19.9 mi).

Tsunami warning center here:
http://ptwc.weather.gov/ptwc/?region=1&id=pacific.2011.04.07.143955

 

[Taxidermista]

This last 7.1 quake happened only 12 miles away from Onagawa nuclear plant.

7.1 2011/04/07 14:32:42 38.253 141.640 49.0 NEAR THE EAST COAST OF HONSHU, JAPAN

NISA: Onagawa Nuclear Power Plant started emergency power generator, 1 external power-line left, so continue to cooling the fuel rod down

 

[tsutsuji]

Hope someone can find the live Fukushima video of the current 7.4 quake and tsunami expected to hit about now.

If such a video exists, it must be quite dark, because it is in the middle of the night.

This last 7.1 quake happened only 12 miles away from Onagawa nuclear plant.

7.1 2011/04/07 14:32:42 38.253 141.640 49.0 NEAR THE EAST COAST OF HONSHU, JAPAN

NISA: Onagawa Nuclear Power Plant started emergency power generator, 1 external power-line left, so continue to cooling the fuel rod down

The radioactivity monitoring at http://www.tohoku-epco.co.jp/electr/genshi/onagawa/mp.html seems to be OK by now.

 

[Jorge Stolfi]

good work

Beware that there is an artificial Earth bank (and possibly some low hills) just west of the plant. Depending on the viewpoint, the bank will hide the lower half of the reactor buildings.

 

[ivars]

I predicted such larger late aftershocks may come here, on March 27th:

http://saposjoint.net/Forum/viewtopic.php?f=54&t=1245&start=1040#p31381"

And this may be not the last, but first, and not the biggest one.

 

[Jorge Stolfi]

Your scenario has three complications.

I have been almost entirely convinced that those straight tubes are not fuel rods.

Wiring or fluid ducts seem unlikely: ripping them off the walls/ceiling should have bent them at the attachment points. (As for loose spare ducts, why keep them on the working floor?)

Someone claimed they look like neutron-measuring instrumentation tubes; I suppose that is it.

 

[Joe Neubarth]

This last 7.1 quake happened only 12 miles away from Onagawa nuclear plant.

7.1 2011/04/07 14:32:42 38.253 141.640 49.0 NEAR THE EAST COAST OF HONSHU, JAPAN

NISA: Onagawa Nuclear Power Plant started emergency power generator, 1 external power-line left, so continue to cooling the fuel rod down

41 miles out to sea from Sendai.

 

[Joe Neubarth]

<sarcasm>Wouldnt TEPCO report that?</sarcasm>

Seriously - TEPCO has no possible way to state anything about the effect of the quake, since they don't have access to large parts of the plant due to radiation.

They can claim "Not identified any immediate damage in the areas that we can monitor".

But it is not valid to say "no additional damage", sorry

It was 40 miles closer than the 9.0 quake. Allowing for attenuation of the shockwaves from the epicenter, it should not have done much damage to intact structures. The non-intact structures are what we need to worry about if we are prone to worry.

 

[flyingblind]

Thank you for the great, well-organized site. Are you the author?

Author No.

 

[shogun338]

Thats the last thing they need is for another plant to have cooling failure . Two out of three external power lines to the Onagawa nuclear power plant, 75 miles northeast of Fukushima and near the epicenter of Thursday's temblor, have been damaged, causing power loss. The plant, operated by Tohoku Electric Power, has been shut down since the March 11 quake and has been relying on external power to cool the reactors. Japan’s Atomic Energy Agency said the two lost power lines were not being used for cooling when tonight’s earthquake hit.
http://www.csmonitor.com/World/Asia...sunami-warning-lifted-but-Fukushima-evacuated

 

[shogun338]

Toshiba Corp submitted a proposal to Tokyo Electric Power Co and the Ministry of Economy, Trade and Industry to dismantle the damaged Fukushima Daiichi nuclear power plant by 2020 http://www.reuters.com/article/2011/04/07/toshiba-idUSL3E7F73E720110407

 

[Sirius (b)]

Greetings everyone.

Here's the EQ information: http://quakes.globalincidentmap.com/; http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.html & http://geofon.gfz-potsdam.de/eqinfo/list.php

And this is a result of a FOIA to NRC: http://fukushimafaq.wikispaces.com/file/view/rst+assessment+26march11.pdf

This report was quoted in the NYT article, but we have more details now,

On Unit 3:

Primary Containment
Damage suspected (NISA, TEPCO) "Not damaged" (JAIF 10:003/25); Fuel pool is heating up but is adequately cooled, and fuel may have been ejected from the pool
(based on information from TEPCO of neutron sources found up to 1 mile from the units, and
very high dose rate material that had to be bulldozed over between Units 3 and 4. It is also
possible the material could have come from Unit 4);

ASSUMPTIONS: Rad Levels: DW 5100 R/hr, torus 150 R/hr (Industry); 100 R/hr debris outside Rx
building (covered).

SNF pool in number 3 is not the only worry that should captivate you, there's been a steam/thermal explosion in RPV, top of PCV breach with some of the debris landing SW of Unit 3-4 - where 3 out of 5 soil samples had been taken, contained pu- isotopes - http://www.tepco.co.jp/cc/press/betu11_j/images/110328n.pdf



Added: Unit 3 thermal imagery, March 20th, 2011, looking West:
http://img535.imageshack.us/img535/591/reactor3fuel.th.jpg

 

[ivars]

Many nuclear facilities have lost onsite or off-site power.

http://www.iaea.org/newscenter/news/tsunamiupdate01.html"

Onagawa Nuclear Power Plant:

NISA has confirmed that two out of the three lines supplying off-site power to the site were lost following the 7 April earthquake. Off-site power continues to be supplied through the third line.

Cooling of the spent fuel pool was temporarily lost, but has subsequently been restored.

Higashidori Nuclear Power Plant

NISA has confirmed that the Higashidori NPP was shutdown and in a maintenance outage at the time of the 7 April earthquake. Off-site power has been lost. Emergency power supply to the site is operating.

Rokkasho Reprocessing Plant

NISA confirms that Rokkasho Reprocessing Plant and uranium enrichment facility lost off-site power. Emergency power supply to the site is operating.

Now all what is needed is another aftershock of size >M7 to knock emergency power supply out.

 

[rmattila]

Not being familiar with the GE ECCS & MCP design, I have some worries about the status of the core cooling:

if the route through which water is being injected to the core is such that the flow either goes entirely through the feedwater nozzles or is divided between the core spray and the feedwater route, then it might be possible that

• the core spray nozzles have been clogged due to prolonged use of seawater (impurities, salt deposits)
• the water goes mainly or entirely to the downcomer, not on top of the core
• furthermore, if the main circulation loops have developed leaks, water will escape from the bottom of the downcomer to the recirculation loops and then to the leak

Adding to this the (i presume by now ascertained) fact that the level measurement monitors the level in the downcomer, not in the core, and the possibility that at least the upper temperature measurement monitors the temperature of the core vessel close to the feedwater inlet (=area affected by the inflow through feedwater lines), this currently leaves us very little on which to base estimates on the state of the cores. As I see it, it could be that only a little part (if any) of the water injected in the reactor vessel actually ends up cooling the core.

Based on the above guesses (I repeat that I really don't know the design details of the GE BWR:s very well), I think that the water samples collected from different parts of the plant could currently provide very important information regarding the degree of core damages. However, some of the nuclides that could be used to indicate high core temperatures (such as Sr-90) require rather sophisticated methodology to be identified, and I'm not sure the analysis methods currently used provide very good information regarding the important indicator nuclides.

Would somebody have better information on the core injection routes used at the Fukushima Dai-ichi plants? Is there some way to ascertain that the water injected in the reactor vessel actually reaches the core?

 

[Idaho_246]

If that's the case (and it may be), it is not a bit surprising that (a) the sound effects person added in all the rumbling noises as well as the dramatic bangs and (b) counterintuitively chose to add 3 bangs rather 1 or perhaps 2.

The sound may have been traveling a much more direct route to the mike than you experienced in those London bombs. Unless you were on top of Hampstead Heath or Crystal Palace (or the like) at the time, there would have been a lot more reflection/muffling etc from buildings between the explosions and your ears.

Someone earlier cited the timing as proof the sound was artificial. That isn't exactly proof - if the timing is off, the soundtrack may just have been shifted in time against the video so the sound was a closer match to the picture for TV purposes.

Is it possible that the soundtrack is from the reactor 2 explosions.

 

[MadderDoc]

[PLAIN]http://i.min.us/im7mIU.jpg[/QUOTE]

Part of the fhm from unit 3 may after initial service deck impact have rebounded, or slid off the deck, to land further down in the building which is annexed to the north face of the reactor building. See attachment with a top view with a arrow pointing to the spot, and a ground shot photo, looking up to the penetrated wall. About in the same area at groundlevel can be seen several smaller machine parts, perhaps of fhm3 origin.

Btw, interesting how the water spraying for cooling and 'firework' has had the effect of washing off a lot of dust since March 20th, revealing more clearly in video and photo what is in that big NW corner pile of debris.

http://www.gyldengrisgaard.dk/fuku_docs/perhaps_also_fhm3part_here.jpg

[URL]http://www.gyldengrisgaard.dk/fuku_docs/perhaps_also_fhm3part_here_groundshot.png[/URL]

 

[shogun338]

Part of the fhm from unit 3 may after initial service deck impact have rebounded, or slid off the deck, to land further down in the building which is annexed to the north face of the reactor building. See attachment with a top view with a arrow pointing to the spot, and a ground shot photo, looking up to the penetrated wall. About in the same area at groundlevel can be seen several smaller machine parts, perhaps of fhm3 origin.

Btw, interesting how the water spraying for cooling and 'firework' has had the effect of washing off a lot of dust since March 20th, revealing more clearly in video and photo what is in that big NW corner pile of debris.

http://www.gyldengrisgaard.dk/fuku_docs/perhaps_also_fhm3part_here.jpg

I have been looking at that corner on Unit 3 for awhile now . In some of the videos it almost looks like a dome . The is something large there .

 

[Sirius (b)]

The image Fred is showing looks like the lid of the RPV, you may want to compare it against early thermal imagery. ;)

 

[Joe Neubarth]

Thats the last thing they need is for another plant to have cooling failure . Two out of three external power lines to the Onagawa nuclear power plant, 75 miles northeast of Fukushima and near the epicenter of Thursday's temblor, have been damaged, causing power loss. The plant, operated by Tohoku Electric Power, has been shut down since the March 11 quake and has been relying on external power to cool the reactors. Japan’s Atomic Energy Agency said the two lost power lines were not being used for cooling when tonight’s earthquake hit.
http://www.csmonitor.com/World/Asia...sunami-warning-lifted-but-Fukushima-evacuated

They still have their emergency diesel generators as back up for each reactor.

 

[|Fred]

lid is color coded yellow <=100% certain
green is color for FHM and crane <=100% certain
pink is color code for (hydraulic stuff) <= guessing

 

[Sirius (b)]

They still have their emergency diesel generators as back up for each reactor.

Indeed, but how long is the fuel going to last, batteries next? With destroyed electric grid in several prefectures (downed pylons, blown transformers) they are in a race against time with Higashidori NPP, possibly Onagawa's SNPs (reactors in cold shutdown as of March 11th).

lid is color coded yellow <=100% certain
green is color for FHM and crane <=100% certain
pink is color code for (hydraulic stuff) <= guessing

Pink is the guard railing around SNF & equipment pools. PCV dome could be inside turbine building of Unit 3, or it could be in the ocean.

 

[shogun338]

Indeed, but how long is the fuel going to last, batteries next? With destroyed electric grid in several prefectures (downed pylons, blown transformers) they are in a race against time with Higashidori NPP, possibly Onagawa's SNPs (reactors in cold shutdown as of March 11th).



Pink is the guard railing around SNF & equipment pools. PCV dome could be inside turbine building of Unit 3, or it could be in the ocean.

Thats what I was thinking about fuel running out . I think the guard rails around the spent fuel pools are covered in a green fabric or plastic . If you look in Unit 4 where there pumping water you can still see part of it below the FHM . The pic posted of it before the accident also shows green covered rails .

 

[Giordano]

I'm intersted in the amount of radioactive material leaked into the sea.

My attempt to estimate the ocean pollution of Cs-137 from the leak that was fixed the day before yesterday:

2 l/s -> 3600 m3 in three weeks.

Concentration of Cs-137 is assumed to be 1.8 MBq/cm3

Which gives 6.5 PBq of Cs-137 from one leak!

(Chernobyl totally released 85 PBq of Cs-137 in aerosol form according to Wikipedia)

Is my estimate reasonable? Can anyone make a better one?

Regarding the assumption of Cs-137 concentration:
http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110405e30.pdf
http://www.tepco.co.jp/en/press/corp-com/release/11040506-e.html

 

[Borek]

2 l/s -> 3600 m3 in three weeks.

Concentration of Cs-137 is assumed to be 1.8 MBq/cm3

Which gives 6.5 PBq of Cs-137 from one leak!

You are assuming constant contamination all the time.

 

[|Fred]

Giordano this may help

French scientists simulate how the radioactivity dilutes into the Pacific Ocean : http://sirocco.omp.obs-mip.fr/outils/Symphonie/Produits/Japan/SymphoniePreviJapan.htm
See also the simulation after 72 days on page 8/9 of http://www.irsn.fr/FR/Actualites_pr...ident-Fukushima-sur-milieu-marin_04042011.pdf