Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[Rive]

Why not? I am well aware that Japan has not the area of Ukraine. However, I think the cost of a successful cleanup far outweighs the benefits. An improper cleanup would end up killing people. It would be like living in a minefield. Some parts of Asia are accustomed to exactly that, sadly, but I don't think the average Japanese citizen would like it, even as a prospect, let alone a day to day reality.

As you said, they have more limited amount of area than Ukraine. Otherwise they must develop something to threat contaminated areas effectively anyway: accumulation works everywhere, so hot spots will be formed even outside the exclusion zone.

IMO every wastewater pipe and treatment facility within in 200km radius (or even more) is a potential 'minefield'. Even now.

Wash the soil from a 600 square Km area? The mighty AREVA can't even muster resources to process a couple thousand tons of low-radioactive water a month.

Excess capacities are always hard and long to set up.

 

[PietKuip]

Why not? I am well aware that Japan has not the area of Ukraine. However, I think the cost of a successful cleanup far outweighs the benefits. An improper cleanup would end up killing people. It would be like living in a minefield.

The real estate would have little value. It will be difficult to sell agricultural products from the area, when even tea leaves from south of Tokyo are more radioactive than the limits. The supply of housing will be much greater than demand - what parents want to raise a family there? And then there is this weird "shunning" of people from contaminated areas in Japan.

Make this into an area for forestry.

 

[clancy688]

You could try a similar decontamination as in Chernobyl. Only decontaminate streets and buildings.
As long as the people stay inside the decontaminated zone, traveling and working should be possible. There's no sense in decontaminating a meadow, for example.
Nobody wants to live in such a zone, and decontamination of everything there is impossible, as already stated. But they could still try to decontaminate only the most necessary spots in order to establish an economoy in that region again.

 

[tsutsuji]

Demolish every house

Why demolish ? Shouldn't washing the outer surface of walls and roof be enough ?

Here is what a French expert team wrote before the Fukushima crisis (in May 2010) about the actions to be undertaken in the zone where populations are allowed to live, albeit under restrictions. The following is therefore not applying to the relocation zone (the most contaminated area where people are not expected to have their dwelling any longer), but it gives an idea of what can/must be done :

The main contamination reduction measures listed hereafter are detailed in Appendix 9, Part 3 of the Guide entitled “Nettoyage dans le milieu bâti (hors zone d’éloignement éventuel)” [Building Clean-Out (excluding possible clearing zone)]:
 clean-out operations in buildings, to be undertaken by specialised teams, such as the Fire and Rescue Brigade, Civil Security or private enterprises;
 contamination fixation/stabilisation techniques aimed at limiting loose dust or skin contamination;
 measures to be taken by residents, such as:
- washing floors with a moist cloth, taking care to move from the washed zones to zones assumed to be still contaminated;
- cleaning aeration grids and home ventilation systems;
- vacuuming furniture surfaces, rugs and carpets.

Whatever the case, measures shall be adjusted to the level and type of risk involved. For instance, it is not specifically recommended that individuals wash their vehicles in ZPPs. Likewise, any roads cut off during the emergency phase may return to use without having been cleaned. The use of these vehicles and roads will trigger only very low additional exposure, which is negligible when National Preparedness Guide for Emergency Phase Way-Out Working Document - May 2010 58/67 compared to the resources that would have to be mobilised to carry out the cleaning and the related environmental restrictions. It should be noted that outdoor decontamination activities are less of a priority then indoor decontamination. The disposition of waste products will need to be decided before such activities could begin. However, residents may themselves take part in the decontamination of their own property once such work begins (i.e. garden, lawn, etc.).

p.57-58 http://www.asn.fr/index.php/content/download/29754/182511/file/Guide+Sortie+Phase+Urgence_UK.pdf

p.36/55 of the cited Appendix 9, Part 3 ( http://www.asn.fr/index.php/content/download/25882/155306/file/Guide+SPU+Annexes+explicatives+V0+14mai2010.pdf ) has the following comment after detailing firehose and high pressure cleaning :"The efficiency is about 30% for buildings' walls and roofs and 50% for roads and pavements if the action is undertaken within one week after a dry deposit."

 

[zapperzero]

Why demolish ? Shouldn't washing the outer surface of walls and roof be enough ?

Here is what a French expert team wrote before the Fukushima crisis (in May 2010) about the actions to be undertaken in the zone where populations are allowed to live, albeit under restrictions. The following is therefore not applying to the relocation zone (the most contaminated area where people are not expected to have their dwelling any longer), but it gives an idea of what can/must be done :

Why don't you read the references you post? Those are guidelines for decon in the case of a moderate accident - defined as less than 24 hours of continuing radiation release. We're way past that.

EDIT: also, if you wash, where does the water go? It is radioactive now, remember?

 

[jlduh]

on 23 May NHK reported http://www3.nhk.or.jp/daily/english/23_25.html


on 24 May NHK report the following NISA instruction to Tepco http://www3.nhk.or.jp/daily/english/24_38.html


this is a surprise no finalised water storage and treating plans
(If I remember correctly the Areva plant should be operating by 1st June.)

And if this (the Areva treatment facility) doesn't happen as announced, then I would say it has been an other... lie? Or maybe just cultural sense of honor implying to make reality look nicer, if you prefer (please don't take it bad, I'm just teasing you a little bit based on the post from the other thread, but no bad intent in y mind...)

As i said several times, ocean will be the final containment I'm afraid, once they will have flooded the all site and all the basements. But some brilliant calculations will obviously confirm that there is no danger for health as it will be diluted. Reality can be nice when embellished (after "augmented reality", maybe "embellished reality" could be an interesting concept (sarcasm inside))

In additon, some typhoon or heavy rain could increase quickly the amount of water (anyway a good part of the contamination around the building, even being sprayed by some sticky compound, will be washed away by heavy rain and end in the ocean; I don't know how this fixing green product is resisting to rain water by the way).

Let's do a quick calculation:

In this area of Japan, the annual rainfall is around 1250mm/year, with most of the rain in the June to September period.

If i take a perimeter of only 400m by 1000m to describe the surface near the reactor buildings (which is only the very near area from them), you end up with a total rainfall over one year of: 400 x 1000 x 1,250 = 500 000 M3 so this is no less than 500 000 tons of rain water that this area, highly contaminated, will receive in one year...

We can consider that half of this will be in the three or four month (based on the rainfall curve) of rainy season: so we can expect that 250 000 tons of water will fall in this messy area in the next months... so you will have an heavy wash without any Areva intervention!

This should give you an idea of what we are talking about containing this contaminated mess.

 

[zapperzero]

You could try a similar decontamination as in Chernobyl. Only decontaminate streets and buildings.
As long as the people stay inside the decontaminated zone, traveling and working should be possible. There's no sense in decontaminating a meadow, for example.
Nobody wants to live in such a zone, and decontamination of everything there is impossible, as already stated. But they could still try to decontaminate only the most necessary spots in order to establish an economoy in that region again.

What is your plan for preventing children and their pets from playing in flowered meadows?

 

[clancy688]

What is your plan for preventing children and their pets from playing in flowered meadows?

Not living there.

As I said, "traveling and working should be possible". I didn't talk about living there.

 

[jlduh]

What about one of units earthquake damage ? There was something in Discovery movie, US tepco worker told that after quake there was crack in reactor building ? But which unit ?
Here: http://www.youtube.com/watch?v=PTQ-Jky_fr8&feature=player_detailpage#t=203s
And here: http://www.youtube.com/watch?v=PTQ-Jky_fr8&feature=player_detailpage#t=289s

SEE THE EDIT BELOW BEFORE READING!

Based on this picture for example:http://www.netimago.com/image_203718.html *

and also on this footage (T=0'53 to 1'02 )
http://www.youtube.com/user/modchannel#p/a/u/0/ZKFGavZ_rf4you can see there is a big vertical crack in the East wall of reactor building N°2 (all along one structural pillar it seems).

You can see a similar one just at the right of it in the wall of N°1, aligned again with a pillar.

This shows that the buildings structures have experienced some move, and the moving pillars have probably cracked the walls. This is an other element towards more structural damage to these reactors by the quake than being stated by Tepco for 2 months.

EDIT: I'm wondering though: is it a crack or a staircase or something else?

Sorry if this has been previously adressed! But I checked and for sure these black lines were there before the quake. But on the footage listed, looking closely, you can see some cracks and damage in this area... So?

 

[Rive]

you can see there is a big vertical crack in the East wall of reactor building N°2 (all along one structural pillar it seems). You can see a similar one just at the right of it in the wall of N°1, aligned again with a pillar.

Sorry, but I see only some ruins of a ladder, not cracks.

Check them there: http://4.bp.blogspot.com/-N_hKjH4OtP0/TX661aLmNdI/AAAAAAAAA_0/N2GLnVHVVbM/s1600/Fukushima.jpg

 

[zapperzero]

Not living there.

As I said, "traveling and working should be possible". I didn't talk about living there.

Possible... maybe. How about necessary? Is it necessary to put many people at risk just so you don't move a couple factories? Why make them commute to a radioactive zone?

 

[zapperzero]

The real estate would have little value. It will be difficult to sell agricultural products from the area, when even tea leaves from south of Tokyo are more radioactive than the limits. The supply of housing will be much greater than demand - what parents want to raise a family there? And then there is this weird "shunning" of people from contaminated areas in Japan.

Make this into an area for forestry.

Yeah just make sure you don't actually use the lumber for anything. Trees are real good at filtering water and air alike. What happens to the filter? It gets dirty.

 

[zapperzero]

As you said, they have more limited amount of area than Ukraine. Otherwise they must develop something to threat contaminated areas effectively anyway: accumulation works everywhere, so hot spots will be formed even outside the exclusion zone.

IMO every wastewater pipe and treatment facility within in 200km radius (or even more) is a potential 'minefield'. Even now.

Excess capacities are always hard and long to set up.

600 square kilometers or 1200 or 2400 is nothing. Japan has a land area of 400000 square Km. Most of the relocation zone is lost and will remain lost. Deal with it. Some other areas will be lost later, depending on how the pollution moves around and if new stuff happens.

 

[clancy688]

Japan has a land area of 400000 square Km. Most of the relocation zone is lost and will remain lost.

Unfortunately most of that area is uninhabitable mountain land.

 

[jlduh]

http://www3.nhk.or.jp/daily/english/25_07.html

High levels of cesium detected above No.1 reactor
The operator of the Fukushima Daiichi nuclear plant says the density of radioactive cesium above the No.1 reactor is 18 times the permissible level for the edge of the plant's compound. On Sunday, Tokyo Electric Power Company began measuring the density of radioactive elements above the No.1 and No.4 reactors.

The firm used instruments attached to the crane pumps that are injecting water into the reactors.TEPCO detected 360 becquerels of cesium-134 per cubic meter above the No.1 reactor, where most of the fuel rods are believed to have melted. The amount is 18 times the allowable limit for the plant's perimeter.

The firm also discovered 7.5 times the limit of cesium-134 above the No.4 reactor, which has no fuel in its core. The substance is believed to have come from the fuel storage pool and the neighboring No.3 reactor.

 

[AntonL]

Unfortunately most of that area is uninhabitable mountain land.

http://www.google.com/search?q=terr...t=mode&cd=2&ved=0CBkQ_AUoAQ&biw=1221&bih=639" how to solve the mountain problem

 

[AntonL]

I am quoting some posts from the political thread

some facts:
1. Reactor http://search.japantimes.co.jp/cgi-bin/nn20110517x1.html" after the quake and before the tsunami (Tepco should publish their official findings regarding this soon as instructed by NISA)

2. http://search.japantimes.co.jp/cgi-bin/nn20110516a3.html" at unit 1 well before the explosion indicating a possible breach in containment caused by earthquake.

So for a change, Gunderson statements are (part) true.

Will they reveal that N°2 and N°3 got also hit by earthquake?

As a matter of fact, yes, at least for Unit 3. From this morning's paper:

http://www.asahi.com/special/10005/TKY201105240733.html

Summary: Unit 3 ECCS (Emergency Core Cooling System?) may have been damaged by the earthquake, before the tsunami arrived.

and now http://www3.nhk.or.jp/daily/english/25_30.html

Quake may have damaged key piping at No.3 reactor

Tokyo Electric Power Company has released data which suggests the March 11th earthquake damaged a critical piping system in the No. 3 reactor at its Fukushima Daiichi nuclear plant.

The utility said that analysis of pressure and temperature data from the days after the quake shows that the No.3 reactor lost its cooling system on March 13th. Much of its nuclear fuel likely melted down and collected at the bottom of the pressure vessel over the next 24 hours.

The analysis also shows that piping in an emergency cooling mechanism, known as a high-pressure coolant injection system, may have been damaged by the earthquake. The system is designed to maintain the water level inside the reactor vessel during an emergency.

The system is known to have automatically switched on shortly after noon on March 12th.

Pressure inside the reactor, which was 75 atmospheric pressure, plunged to about 10 atmospheric pressure over the next six hours.

Tokyo Electric says the drop in pressure is consistent with analysis which assumes the piping system had been damaged.

The piping system is one of the plant's most important structures in terms of safety, and must be damage-proof.

Tokyo Electric refuses to confirm, however, that the key piping system was damaged by the quake, and suggests that it is possible a gauge malfunction may be to blame for the data fluctuation.

Experts note that extensive investigation is needed to examine whether the massive earthquake damaged the cooling system.
Wednesday, May 25, 2011 18:46 +0900 (JST)

So it seems that the quake did cause some severe damage to the integrity of the plants

Also remember Unit 6 is collecting water in both the basements of the reactor and turbine buildings.

In conclusion - the NPP are not that earthquake safe as previously thought!

 

[tsutsuji]

This is an other element towards more structural damage to these reactors by the quake than being stated by Tepco for 2 months.

I could note the following evolution in news reports :

On April 19th http://www.yomiuri.co.jp/dy/national/T110418004891.htm was talking solely about reinforcing reactor building No 4.

On May 17th, as I previously wrote, http://www.zakzak.co.jp/society/domestic/news/20110517/dms1105171643027-n1.htm said "reinforcing the reactor buildings at earthquake-and-tsunami-damaged all units １～４ is being considered".

Tepco does not seem to be so shy any longer about suspecting structural damage everywhere. Conversely we know that structural damage assesment was performed before starting to move contaminated water to the Waste treatment facility's buildings (1). So at least the two concerned waste treatment buildings seem to be OK. I don't know if Tepco issued any other structural damage assessment concerning any other building.

(1) "The high-temperature incinerator building has retained its structural integrity, as confirmed through seismic response analysis using seismic ground motion documented to date, as well as through inspections following the Tohoku District-Off the Pacific Ocean Earthquake." : http://www.nisa.meti.go.jp/english/files/en20110520-2.pdf

 

[Astronuc]

some facts:
1. Reactor http://search.japantimes.co.jp/cgi-bin/nn20110517x1.html" after the quake and before the tsunami (Tepco should publish their official findings regarding this soon as instructed by NISA)

I believe the reactor (power generation) was shutdown manually just after the quake. The reactor cooling was working at the time. Normally, even at shutdown, the cooling continues.

2. http://search.japantimes.co.jp/cgi-bin/nn20110516a3.html" at unit 1 well before the explosion indicating a possible breach in containment caused by earthquake.

That very well could be. In other words, the quake may have damage the core or cooling systems and/or containment.

The press/media are frequently not careful with wording.

 

[Astronuc]

In conclusion - the NPP are not that earthquake safe as previously thought!

Or it means that the earthquake accelerations exceeded the design basis. We know that some of the local ground acceleration exceeded the design accelerations.

We also know that in other areas outside of the plant, the local ground accelerations were even greater.

So the site is not a good place for a plant of that particular design.

 

[~kujala~]

Good you posted this again Anton:
http://search.japantimes.co.jp/cgi-bin/nn20110516a3.html

As here they are explaining (hopely some expert has made some calculations?) that rising pressure alone cannot explain the findings in unit 1:

The source of the steam was believed to be the No. 1 reactor's overheated pressure vessel.

But for that scenario to hold, the pressure in the reactor would have to have reached enormous levels ~~~- damaging the piping and other connected facilities. It should have taken much more time to fill the entire building with steam.

 

[Borek]

To all: please stick to the NPP. From now on I am going to delete all posts on rice planting in Japan, land decontamination and so on. You all like this thread for technical content, but you derail it at every occasion.

 

[tsutsuji]

I am quoting some posts from the political thread

some facts:
1. Reactor http://search.japantimes.co.jp/cgi-bin/nn20110517x1.html" after the quake and before the tsunami (Tepco should publish their official findings regarding this soon as instructed by NISA)

Summarizing "was shut down manually" what the Japan Times wrote "may have been shut down manually" and "it is unknown whether it was open", takes the risk of underestimating the level of uncertainty concerning this point, until the official findings are published.

See also https://www.physicsforums.com/showthread.php?p=3305338#post3305338 where I mention another news article elaborating on this nuance, and the possibility that the cooling was shut by some earthquake-related dysfunction.

 

[AntonL]

Summarizing "was shut down manually" what the Japan Times wrote "may have been shut down manually" and "it is unknown whether it was open", takes the risk of underestimating the level of uncertainty concerning this point, until the official findings are published.

See also https://www.physicsforums.com/showthread.php?p=3305338#post3305338 where I mention another news article elaborating on this nuance, and the possibility that the cooling was shut by some earthquake-related dysfunction.

extract from http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e13.pdf" showing that the isolation condensers where shut down 11 minutes after automatic start up with a note justifying the reason for this intervention ( we presume that this is a manual operation)
[PLAIN]http://k.min.us/i2Dqk.JPG

 

[Rive]

Tepco does not seem to be so shy any longer about suspecting structural damage everywhere. Conversely we know that structural damage assesment was performed before starting to move contaminated water to the Waste treatment facility's buildings (1). So at least the two concerned waste treatment buildings seem to be OK. I don't know if Tepco issued any other structural damage assessment concerning any other building.

Regarding the structural considerations: to pump out the groundwater from the basement of a building is always dangerous (and in most cases it's more devastating than the high groundwater itself). And judging by the limited success of the pumping actions the water in the turbine buildings (and maybe in the reactor buildings) is connected with the groundwater.

I'm concerned and worried without even considering suspected EQ damages.

 

[Borek]

Well, these are also related to the accident, so they will reappear regularly here if they don't have a separate topic. Maybe it would be better to split it to separate threads (is it possible here to split an existing thread?) (both child with detailed description)(what about an off-site and in-site thread?) than just delete the 'related-but-not-so-closely' parts.

To Borek : please say if this sort of post is allowed here. If not, I suggest to create a different thread entitled "consequences outside Fukushima NPP" .

New thread is a good idea. It won't be complete - there is plenty of good information already posted here, and nobody is going to browse 8k posts to check which ones should be moved.

It is here: https://www.physicsforums.com/showthread.php?t=501637

Regarding my post: what I was aiming at was that the discussion about what Japanese people should do with their own country and where they should start planting rice was becoming a pissing contest, completely not related to the problem at hand. I tried to do some cleaning, but it wasn't clear which posts to leave and which to delete, so I decided to just warn everyone to keep on topic. That's sometimes faster than sending several PMs/warnings and working behind the curtain.

 

[tsutsuji]

The following attachments are from the May 6th video from Tepco posted earlier at https://www.physicsforums.com/showthread.php?p=3306574#post3306574

1- Is the big grey cylindric object a part of a seawater pump ?
2- What are the reddish tronconic objects ?

 

[Astronuc]

The Daily Yomiuri Online has posted diagrams describing fuel melting in reactors 1,2 and 3, based on info from TEPCO. Anyone care to comment on the plausibility and/or likelihood of these scenarios?

http://www.yomiuri.co.jp/dy/national/T110524006012.htm
http://www.yomiuri.co.jp/dy/photo/DY20110525102058990L0.jpg

Having 'partially damage' (light green) above significant melting (brown) is rather odd/strange/seemingly unlikely. Molten fuel would not support any solid structure. Anything above the melting would likely be severely damaged.

 

[Rive]

The following attachments are from the May 6th video from Tepco posted earlier at https://www.physicsforums.com/showthread.php?p=3306574#post3306574

1- Is the big grey cylindric object a part of a seawater pump ?
2- What are the reddish tronconic objects ?

The big grey is the motor of the pump. The reddish parts looks like the underground components of a/the pump.

It's interesting to see them together this way. I doubt that the tsunami could pull out the underground parts (and I can't recall any relevant picture from previous media releases), so maybe they were removed later, but I have no idea why.

 

[~kujala~]

Still, there are two new releases.

Summary of the analysis - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e13.pdf
Status of reactor cores 2 and 3 - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf

Well well... TEPCO has finally admitted that water levels do not necessarily tell anything about the actual water levels. This is the worst-case scenario for units 2&3 (scenario 2) whereas in scenerio 1 measured values show the actual water levels. The full meltdown of units 2 & 3 is based on the case 2:

Case 2 (water level was dropped): Measured values don't show the actual water levels
In case 2, after drawdown, although water was injected, the water level kept below the bottom of active fuel

http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf
(page 3)

And from this picture:
http://www.yomiuri.co.jp/dy/photo/DY20110525102058990L0.jpg

Reactors Nos. 2,3 show worst-case scenarios

This is something rmattila predicted a long time ago. There is even a separate thread concerning this matter:

https://www.physicsforums.com/showthread.php?t=485505
"Level measurement in GE BWRs" (dated March 29th)

And again rmattila was worried about water levels here:
https://www.physicsforums.com/showpost.php?p=3298394&postcount=6912

 

[tsutsuji]

1. The conductivities say that these are 0.5x seawater. Will Areva's precipitation protocols work in seawater? Is this seawater together with all the things that are added to precipitate Cs and Sr what TEPCO claims they'll be using to cool the reactors in perpetuity?

I don't know if that fully answers your question, but page 14 (15/41) https://www.sfen.fr/content/download/30419/1606950/file/2-ICAPP Fukushima Accident_Masui.pdf speaks about a "desalination system" producing "concentrated seawater" as ultimate waste, being installed at the end of the water decontamination unit.

 

[SteveElbows]

Well well... TEPCO has finally admitted that water levels do not necessarily tell anything about the actual water levels. This is the worst-case scenario for units 2&3 (scenario 2) whereas in scenerio 1 measured values show the actual water levels. The full meltdown of units 2 & 3 is based on the case 2:

This is not a brand new concept, TEPCO admitted it the other week when they discovered unit 1 water level readings did not match reality, after sending humans into the building to fix a gauge. This caused them to do a new meltdown estimate for reactor 1, and they said the same might be true at reactors 2 & 3. However they have not actually been able to fix gauges at 2 & 3 yet, so this new analysis of cores at 2 & 3 is based on this theory rather than solid data.

 

[tsutsuji]

The big grey is the motor of the pump. The reddish parts looks like the underground components of a/the pump.

It's interesting to see them together this way. I doubt that the tsunami could pull out the underground parts (and I can't recall any relevant picture from previous media releases), so maybe they were removed later, but I have no idea why.

The grey and reddish objects can also be seen from above on http://www.netimago.com/image_202942.html , between unit 1 and unit 2.

I wonder why I can't see them on Tepco's map : http://www.tepco.co.jp/en/nu/fukushima-np/f1/images/f1-sv-20110323-e.pdf .

 

[andybwell]

Some new informations by EX-SKF again.

http://ex-skf.blogspot.com/2011/05/containment-vessels-of-reactors-1-2-3.html

http://ex-skf.blogspot.com/2011/05/multiple-10-centimeter-holes-in-reactor.html





I'm really anticipating the translated version of this 225 page report. But this will take a while. One month according to TEPCO - http://www.tepco.co.jp/en/press/corp-com/release/11052412-e.html

Still, there are two new releases.

Summary of the analysis - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e13.pdf
Status of reactor cores 2 and 3 - http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf

Typical TEPCO humor again...



To sum it up, we have a INES level 7 radioactivity release, we have 10% of Chernobyl emissions, the whole pacific is now a nuclear waste storage facility and probably half of Fukushima prefecture is an exclusion zone, but that still is not, I quote, a "serious situation" with "large-scale emission of radioactive materials".

Is it possible to get iodine 131 in milk in the USA that is not coming from Fukushima? (criticality? - half life 8.02 days?)
http://cdph.ca.gov/programs/Documents/CDPH-RHB-RadReport-2011-05-16.pdf

 

[zapperzero]

Is it possible to get iodine 131 in milk in the USA that is not coming from Fukushima? (criticality? - half life 8.02 days?)
http://cdph.ca.gov/programs/Documents/CDPH-RHB-RadReport-2011-05-16.pdf

Could be local. Diablo Canyon NPP is right there. More likely not, though. Bio-accumulation sucks.

 

[andybwell]

Could be local. Diablo Canyon NPP is right there. More likely not, though. Bio-accumulation sucks.

Thanks. What about iodine 131 only being produced during nuclear fission?

 

[mscharisma]

Or it means that the earthquake accelerations exceeded the design basis. We know that some of the local ground acceleration exceeded the design accelerations.

We also know that in other areas outside of the plant, the local ground accelerations were even greater.

So the site is not a good place for a plant of that particular design.

Am not sure the first sentence is correct?
This article (overall quite interesting info in it) by the World Nuclear Association states:
"... In March 2008 Tepco upgraded its estimates of likely Design Basis Earthquake Ground Motion Ss for Fukushima to 600 Gal, and other operators have adopted the same figure. (The magnitude 9.0 Tohoku-Taiheiyou-Oki earthquake in March 2011 did not exceed this at Fukushima.)..."

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

Then, on page 4 in a document, to which a link was posted by someone here in this thread a few days back, you'll see ground motion numbers below 600 Gal but some design number being below observed numbers. (pages 5ff deleted by me to reduce file size for upload)

 

[TCups]

and now http://www3.nhk.or.jp/daily/english/25_30.html

So it seems that the quake did cause some severe damage to the integrity of the plants

Also remember Unit 6 is collecting water in both the basements of the reactor and turbine buildings.

In conclusion - the NPP are not that earthquake safe as previously thought!

Perhaps from the reactor pressure vessel acting like a giant clanger in a bell?

See post 2935:

"If the lateral acceleration forces exceed the design parameters, the pressure vessel risks becoming the upside down clanger in a giant bell shaking at about a 9 on the Richter scale.

The key vulnerable structure if that happens is the high pressure steam outlet pipe. If that cracks or leaks, then you have high pressure steam and shortly thereafter, hydrogen in the primary containment, but not in a huge blast, as the torus suppression pool is meant to (hopefully) handle. Apparently that didn't work out so well at Unit 2."

https://www.physicsforums.com/showpost.php?p=3230713&postcount=2935

http://i306.photobucket.com/albums/nn270/tcups/Screenshot2011-04-05at100427AM.png

Here is the emergency high pressure coolant injection system:

https://motherjones.com/files/images/reactor-640-normal.preview.jpg

 

[tsutsuji]

The grey and reddish objects can also be seen from above on http://www.netimago.com/image_202942.html , between unit 1 and unit 2.

I wonder why I can't see them on Tepco's map : http://www.tepco.co.jp/en/nu/fukushima-np/f1/images/f1-sv-20110323-e.pdf .

The trajectories of a number of objects hit by the tsunami in the area next to the intake canal are shown on page 38 of http://www.tepco.co.jp/nu/fukushima-np/images/handouts_110525_01-j.pdf : the purple dots seem to show objects moved by workers before the earthquake for maintenance. Red dots seem to show objects moved by the tsunami wave. So what we see between unit 1 and 2 is probably one of the pumps from unit 4 which had been moved there by workers before the earthquake. The bright blue objects had also undergone a purple dot move from unit 4 to the area between unit 3 and unit 2 before the quake.

The following page http://www.tepco.co.jp/fukushima1-np/b42319-j.html is undated (all it says is it is inpection No 19) but it shows the pumps at unit 3 undergoing inspection. The photograph, showing painting work, makes clear that the reddish parts belong to the pumps. It also says the pumps (each ? or all three put together ?) have a flow of 14 tons per second.

 

[zapperzero]

Am not sure the first sentence is correct?
This article (overall quite interesting info in it) by the World Nuclear Association states:
"... In March 2008 Tepco upgraded its estimates of likely Design Basis Earthquake Ground Motion Ss for Fukushima to 600 Gal, and other operators have adopted the same figure. (The magnitude 9.0 Tohoku-Taiheiyou-Oki earthquake in March 2011 did not exceed this at Fukushima.)..."

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

Then, on page 4 in a document, to which a link was posted by someone here in this thread a few days back, you'll see ground motion numbers below 600 Gal but some design number being below observed numbers. (pages 5ff deleted by me to reduce file size for upload)

Ahh. But this is the very crux of the matter, isn't it? TEPCO proposed and the gov't approved a modification of the design basis numbers. Were they right, or wrong to do so?

 

[Azby]

Having 'partially damage' (light green) above significant melting (brown) is rather odd/strange/seemingly unlikely. Molten fuel would not support any solid structure. Anything above the melting would likely be severely damaged.

I'm imagining that the newsaper's graphic designer had access to a more technical representation, and got some details wrong. I wonder if anyone can find the TEPCO files this diagram was based on?

 

[zapperzero]

I'm imagining that the newsaper's graphic designer had access to a more technical representation, and got some details wrong. I wonder if anyone can find the TEPCO files this diagram was based on?

Well, it could be that the colors actually represent temperature ranges and the chart just gives those temp ranges in terms of how damaged a notional fuel rod would get upon being heated to somewhere in that temp range.

 

[SteveElbows]

I'm imagining that the newsaper's graphic designer had access to a more technical representation, and got some details wrong. I wonder if anyone can find the TEPCO files this diagram was based on?

The TEPCO originals for reactor 2 & 3 are shown within this document:

http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf

 

[tsutsuji]

The following is dated April 21st, so it might have already been posted here : Kanazawa University and an Akita prefecture based company called Kumaken Kougyou claim they have invented a process to treat 1000 tons of water per hour, which is 20 times more than Areva's 50 tons per hour : http://blogs.wsj.com/japanrealtime/2011/04/21/chemist-i-can-clean-fukushima-water-faster/

A May 22 issue of a Colorado local newspaper reports about the involvement of a company called "Industrial Constructors/Managers" :

The Pueblo company is coordinating the production of 97 steel containment units for the radioactive water at Tokyo Electric Power Co.'s stricken nuclear plant in Fukushima, Japan.
http://www.chieftain.com/business/local/answering-japan-s-call-for-help/article_a549f206-841b-11e0-abba-001cc4c002e0.html

 

[dh87]

I don't know if that fully answers your question, but page 14 (15/41) https://www.sfen.fr/content/download/30419/1606950/file/2-ICAPP Fukushima Accident_Masui.pdf speaks about a "desalination system" producing "concentrated seawater" as ultimate waste, being installed at the end of the water decontamination unit.

The diagram shows a "Cs adsorption tower" before the reverse osmosis treatment. My understanding was that Areva was talking about a selective precipitation procedure. For Cs+ removal to be effective, the selectivity has to be enormous. The Na+ and K+ concentrations exceed the Cs+ concentration by many orders of magnitude. This couldn't be a simple ion-exchange resin. In addition, the recent published data show significant amounts of Sr-89 and Sr-90. In the diagram you reference, these radioisotopes will end up in the concentrated seawater.

I don't know much about reverse osmosis, but doesn't it produce a small amount of purified water and a large amount of slightly concentrated starting material? Presumably, that's why the diagram shows evaporation of the reverse osmosis concentrate. But if you're going to evaporate anyway, why not just dispense with everything else?

 

[tsutsuji]

The diagram shows a "Cs adsorption tower" before the reverse osmosis treatment. My understanding was that Areva was talking about a selective precipitation procedure. For Cs+ removal to be effective, the selectivity has to be enormous. The Na+ and K+ concentrations exceed the Cs+ concentration by many orders of magnitude. This couldn't be a simple ion-exchange resin. In addition, the recent published data show significant amounts of Sr-89 and Sr-90. In the diagram you reference, these radioisotopes will end up in the concentrated seawater.

I don't know much about reverse osmosis, but doesn't it produce a small amount of purified water and a large amount of slightly concentrated starting material? Presumably, that's why the diagram shows evaporation of the reverse osmosis concentrate. But if you're going to evaporate anyway, why not just dispense with everything else?

See also the somewhat more detailed diagram page 10 of http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110517e5.pdf

 

[NUCENG]

Ahh. But this is the very crux of the matter, isn't it? TEPCO proposed and the gov't approved a modification of the design basis numbers. Were they right, or wrong to do so?

There are now two design basis numbers for Fukushima. One for inland earthquakes and one for the type of earthquake at sea like that on March 11. The 600 Gal number is for the latter. TEPCO had completed reanalysis and mods (unknown what they did) for the inland earthquakes, but had not finished evaluations for the 600 Gal limit.

See:
https://www.physicsforums.com/showthread.php?p=3289365&highlight=seismic#post3289365
https://www.physicsforums.com/showthread.php?p=3287872&highlight=seismic#post3287872

 

[tsutsuji]

extract from http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e13.pdf" showing that the isolation condensers where shut down 11 minutes after automatic start up with a note justifying the reason for this intervention ( we presume that this is a manual operation)
[PLAIN]http://k.min.us/i2Dqk.JPG[/QUOTE]

I guess that the closing of 3A and 3B are what is shown with red dots on pages 32 and 33 of http://www.tepco.co.jp/cc/press/betu11_j/images/110524a.pdf .

Page 19 (attachment 1-11) shows the "PLR pump entrance temperature" rising again at the point marked with arrow ③, which is when the isolation condenser stops.

See also pressure rising at 15:03 on the graph in the middle of page 24.

The TEPCO originals for reactor 2 & 3 are shown within this document:

http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110524e14.pdf

Some similar-looking diagrams are shown on http://www.tepco.co.jp/cc/press/betu11_j/images/110524a.pdf

page 160 for unit 1
page 173 and 183 for unit 2
page 195 and 206 for unit 3

 

[NUCENG]

As Reuters puts it :


But http://www.chunichi.co.jp/s/article/2011051790014812.html says that while Tepco is emphasizing that the shutdown of the isolation condenser by a worker, in accordance with the manual which instructs to do so when reactor temperature falls by more than 55°C per hour, is one possibility, the other possibility is that the isolation condenser was damaged by the earthquake before the tsunami struck. Tepco says that the second possibility can't be ruled out.

Looking at the graphs for F1-1 at:
http://www.tepco.co.jp/nu/fukushima-np/index10-j.html

The Isolation Condenser was initiated from 1452 hr to 1503 hr as stated in the TEPCO report.
In that time the RPV pressure dropped from 6.8 MPa to 5 MPa. Using steam tables for saturated steam temperatures at those pressures the cooldown rate if allowed to continue was about 212 degC/hr. In fact, in the condition they were in, they should have continued cooling down and ignored the cooldown rate. That rate is for normal shutdown conditions to reduce stress cycling of the vessel and nozzles. If they deliberately isolated the IC, it indicates their training was deficient and they were blindly following normal cooldown limits when they were in a non-normal condition.

Once they secured flow through the IC, there is a potential that noncondensible gases can (eg., hydrogen, amonia, fission product gases) collect in high points in the IC piping. This can air-bind the system defeating natural circulation which is the driving force for this system. That is why they are uncertain if it worked when they later tried to restart the IC.

I see no indication of leaks or damage to the IC system or piping during the time prior to the tsunami covered by the TEPCO data at the link above. It was holding pressure, so I am inclined to believe the isolation was deliberate by operators.

TEPCO is apparently being careful in stating it may have been damaged in the earthquake, but during the few minutes it operated there is normal system response. If they suspected damage to the system they should have isolated the 4 normally open supply valves from the reactor vessel steam area to the IC system shown in the diagram in the TEPCO report, but they haven't indicated that in any of the releases I've seen.

 

[Rive]

Looking at the graphs for F1-1 at:
http://www.tepco.co.jp/nu/fukushima-np/index10-j.html

The Isolation Condenser was initiated from 1452 hr to 1503 hr as stated in the TEPCO report.
In that time the RPV pressure dropped from 6.8 MPa to 5 MPa. Using steam tables for saturated steam temperatures at those pressures the cooldown rate if allowed to continue was about 212 degC/hr. In fact, in the condition they were in, they should have continued cooling down and ignored the cooldown rate. That rate is for normal shutdown conditions to reduce stress cycling of the vessel and nozzles. If they deliberately isolated the IC, it indicates their training was deficient and they were blindly following normal cooldown limits when they were in a non-normal condition.

Even without knowing about the tsunami on way?