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Japan earthquake - contamination & consequences outside Fukushima NPP

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razzz
#37
Jun5-11, 04:09 AM
P: 205
The link is to ex-skf.blogspot.com...
But why were the government experts interested in krypton-85? What does krypton-85 represent? And iodine-129? (The simulation maps are only about krypton-85; they are still sitting on iodine-129 maps or any other maps of other nuclides.)

When it comes to fallout data, either TEPCO has to stop throwing people under the bus or get a bigger bus.
clancy688
#38
Jun5-11, 04:36 AM
P: 546
Quote Quote by razzz View Post
In my opinion, EX-SKF misunderstands the data he found. Those are only mathmatical simulations as for how a cloud of Krypton-85 would've behaved if there would've been one.

There are only two things we can derive from those images: Direction of a possible Krypton-85 plume that day and densitiy over distance based on initial release.
It doesn't show us what really happened.

Krypton-85 is a noble gas. It has a very, very, very short biological half life (the body throws it out as soon as it gets in) and is a beta decayer (it's only a problem if it's inside), so there is probably little to none significance for any health damage.
The nuclear waste facilities Sellafield and La Hague are releasing Krypton gas in the magnitude of hundreds of PBq every year. The converted release of C137 and I131 at Fukushima was 630 PBq. The conversion factor for noble gases (Krypton-85) is zero. (according to the INES manual)
So IAEA is apparently thinking of Krypton-85 as "not dangerous at all".
razzz
#39
Jun5-11, 04:46 AM
P: 205
Quote Quote by clancy688 View Post
In my opinion, EX-SKF misunderstands the data he found. Those are only mathmatical simulations as for how a cloud of Krypton-85 would've behaved if there would've been one.

There are only two things we can derive from those images: Direction of a possible Krypton-85 plume that day and densitiy over distance based on initial release.
It doesn't show us what really happened.

Krypton-85 is a noble gas. It has a very, very, very short biological half life (the body throws it out as soon as it gets in) and is a beta decayer (it's only a problem if it's inside), so there is probably little to none significance for any health damage.
The nuclear waste facilities Sellafield and La Hague are releasing Krypton gas in the magnitude of hundreds of PBq every year. The converted release of C137 and I131 at Fukushima was 630 PBq. The conversion factor for noble gases (Krypton-85) is zero. (according to the INES manual)
So IAEA is apparently thinking of Krypton-85 as "not dangerous at all".
Do you think those wind pattern arrows are made up? We already know what happened, just waiting for the forthcoming confirmation. Maybe in another month or two if ever.
clancy688
#40
Jun5-11, 07:52 AM
P: 546
Quote Quote by razzz View Post
Do you think those wind pattern arrows are made up? We already know what happened, just waiting for the forthcoming confirmation. Maybe in another month or two if ever.
Nope, they are real. What's unreal is the actual dose or amount of the radioactive source.

If there's a 1Bq/h release we get ~ 1^-12 Bq/m in Tokio. I don't know if that scale is linear, but let's assume it is. Then for 1000000 Bq/m Kr-85/I-129/Cs-137 you'd need a release of 10^18 Bq/h.
So if we'd actually KNOW how much material the reactors were spitting out EVERY HOUR during the first two weeks, we could make use of these cards and calculate what radiation hit Tokio. But we don't. And so those cards tell us nothing except "the wind was blowing in direction x at time z" - which we already know.

But again we're straying offtopic with something which fits better in the contamination and consequences thread...
etudiant
#41
Jun5-11, 08:05 AM
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P: 858
Quote Quote by clancy688 View Post
Nope, they are real. What's unreal is the actual dose or amount of the radioactive source.

If there's a 1Bq/h release we get ~ 1^-12 Bq/m in Tokio. I don't know if that scale is linear, but let's assume it is. Then for 1000000 Bq/m Kr-85/I-129/Cs-137 you'd need a release of 10^18 Bq/h.
So if we'd actually KNOW how much material the reactors were spitting out EVERY HOUR during the first two weeks, we could make use of these cards and calculate what radiation hit Tokio. But we don't. And so those cards tell us nothing except "the wind was blowing in direction x at time z" - which we already know.

But again we're straying offtopic with something which fits better in the contamination and consequences thread...
The charts show the level of dilution for a 1 bq/hr source term and suggests that the source level was diluted by about 10**12th by the time it reached Tokyo. Perhaps that is enough information for someone who was monitoring the actual levels reached in Tokyo to work back to derive the corresponding emission level at the source.
clancy688
#42
Jun5-11, 08:10 AM
P: 546
Quote Quote by etudiant View Post
The charts show the level of dilution for a 1 bq/hr source term and suggests that the source level was diluted by about 10**12th by the time it reached Tokyo. Perhaps that is enough information for someone who was monitoring the actual levels reached in Tokyo to work back to derive the corresponding emission level at the source.
Fascinating... it never occured to me to calculate backwards in order to get the source term. Thanks for that hint.

Does somebody know where to find airborne activity measurements for Tokio...?


P.S.
thx @ Borek for moving :)
jlduh
#43
Jun5-11, 08:44 AM
P: 468
Quote Quote by clancy688 View Post
Fascinating... it never occured to me to calculate backwards in order to get the source term. Thanks for that hint.

Does somebody know where to find airborne activity measurements for Tokio...?


P.S.
thx @ Borek for moving :)
I have this table with data it seems from CTBTO measurement network, but as i don't speak japanese i cannot give precisions of where it was measured, i just read the numbers for the various isotopes!

http://www.cpdnp.jp/pdf/110603Takasaki_report_May30.pdf

But this is interesting as you can see that there has been three spikes in the measurements:

- One (the biggest) between March 15 and 16
- One between March 20 and 21 (which fits the "black smoke coming from N3" period)
- One between March 29 and 30

For Tokyo I had a nice curve but i don't find it anymore, damn...

You have also these graphs (but not for Shibuya is Tokyo), but difficult to read:

http://www.netimago.com/image_207151.html



You find the same pattern here:

http://tkynt2.phys.s.u-tokyo.ac.jp/n...v1_all_eng.pdf

Basically, Tokyo was around 0,37 micro Sv/h for March 16, and then 0,17 micro Sv/h after the event of March 21 st.



Found from this page with a lot of links, maybe you'll find what you need:

https://sites.google.com/site/radmon...top_english#11
clancy688
#44
Jun5-11, 09:07 AM
P: 546
Nice... but despite what I wrote before I am being indecisive as to how to apply those measures and cards and stuff exactly...

I'm sure what ZAMG did was basically the same... they got a source term of 4 * 10^16 for C137 on March 14th.
onkeljonas
#45
Jun7-11, 06:53 AM
P: 1
Regarding the thresholds for cleanup of contaminated soil in areas with children:
As far as I understand, the quoted doserates are calculated purely for external exposure.
If true, this ignores that children (especially small children) ingest significant amounts of soil compared to most adults. The obvious (if not only) reason for this, is the fact that children at certain ages simply eat soil.

So my question is: Given known concentrations of radioisotopes in topsoil, how would we calculate dose estimates (from internal exposure) for different amounts of ingested soil?

P.S. First post here - glad to have found a forum concerned with reality more than spin :)
swl
#46
Jun10-11, 12:14 AM
P: 108
From the power plant thread...

Quote Quote by Bioengineer01 View Post
My understanding is that the reported number DO NOT include releases to the Ocean and only air releases and thus the statement that the worse is over. When they consider the true releases to the Ocean, my gross napkin calculations say that they already got Gold!
I don't know about the overall gold, but it seems like this accident is already the ocean contamination champion.

Does anyone know how ocean contamination from Fukushima compares to contamination from bomb testing in and above the ocean?

My wife was recently reading an article from a Japanese women's magazine that was advising readers to avoid eating seafood bones and shells because of the risk of Strontium contamination. It is impressive how so much food/water from so many areas is contaminated now. It makes it that much more difficult to feed the kids (here in Japan) a healthy diet.
etudiant
#47
Jun10-11, 05:12 PM
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Quote Quote by swl View Post
From the power plant thread...



I don't know about the overall gold, but it seems like this accident is already the ocean contamination champion.

Does anyone know how ocean contamination from Fukushima compares to contamination from bomb testing in and above the ocean?

My wife was recently reading an article from a Japanese women's magazine that was advising readers to avoid eating seafood bones and shells because of the risk of Strontium contamination. It is impressive how so much food/water from so many areas is contaminated now. It makes it that much more difficult to feed the kids (here in Japan) a healthy diet.
No easy answer, unfortunately.
Airborne bomb testing ended 50 years ago, with only about 500 tests, most of which were fairly small and involved around 100kg of nuclear material or less. There were some big multi megaton tests, involving tons of uranium and plutonium to give the hydrogen fusion its kick, but these were few, less than 50.
By contrast, Fukushima involves about 250 tons of melted reactor fuel, probably an amount equal to all the atmospheric A bomb tests put together. Plus Fukushima just happened, so the radiation is at its peak.
The complicating issue is that the former USSR had a very relaxed attitude to nuclear power. Old nuclear submarine reactors were scrapped by dumping them into the ocean, along with other nuclear wastes. There are some horror stories of nuclear waste casks getting pounded with hammers to help them fit on some waste fuel barges. Norway and Japan both helped fund cleanups of some of the worst pollution, but the records of what was dumped are very suggestive that a lot was missed.
So the impact of this disaster is a step on a continuum, it is not a new dimension in pollution.

Your problem is that you are getting your seafood from Japanese waters, shortly after a major pollution event, with food safety supervised by a government that is very reluctant to sound the alarm just because some food is more contaminated than before. Afaik, the safest foods will be the pelagic fish, tuna, albacore etc, simply because they are caught far from Japan's shores. By contrast, shrimp, clams, mussels and similar coastal seafood may be problematical. Even seaweed, a wonderful food, may be best skipped for a couple of years, unless you can lay in a stash of pre March 11 product.
It is pointless imho to buy a geiger counter to check your food, the most damaging radiation is alpha particles, which is stopped even by a tissue and which is not detected that readily, but which is most likely to be harmful if ingested. The Russian dissident poisoned by polonium some years back died from the effects of internal alpha particle irradiation.
razzz
#48
Jun10-11, 05:56 PM
P: 205
Quote Quote by swl View Post
From the power plant thread...



I don't know about the overall gold, but it seems like this accident is already the ocean contamination champion.

Does anyone know how ocean contamination from Fukushima compares to contamination from bomb testing in and above the ocean?

My wife was recently reading an article from a Japanese women's magazine that was advising readers to avoid eating seafood bones and shells because of the risk of Strontium contamination. It is impressive how so much food/water from so many areas is contaminated now. It makes it that much more difficult to feed the kids (here in Japan) a healthy diet.
Better to read the site http://ex-skf.blogspot.com/ as he tries to keep up with all aspects of Japan dealing with nuclear power and fallout involving tea. seaweed, to cement, etc. Also. maybe check the Greenpeace site for information as they asked Japan for permission to test seawater and fish near the accident and were refused but try to keep track of the fallout.

On a sensor, the difference in readings from an adult holding it, to a child holding it, to laying on the ground can be 100 fold. Defenseless children are more susceptible to fallout just being nearer the ground as dust kicks up first to their level.
SteveElbows
#49
Jun11-11, 02:18 PM
P: 630
Quote Quote by Bioengineer01 View Post
http://www.zerohedge.com/article/phy...ltdown-might-b
"The recent CDC Morbidity and Mortality Weekly Report indicates that eight cities in the northwest U.S. (Boise ID, Seattle WA, Portland OR, plus the northern California cities of Santa Cruz, Sacramento, San Francisco, San Jose, and Berkeley) reported the following data on deaths among those younger than one year of age:

4 weeks ending March 19, 2011 - 37 deaths (avg. 9.25 per week)
10 weeks ending May 28, 2011 - 125 deaths (avg.12.50 per week)

This amounts to an increase of 35% (the total for the entire U.S. rose about 2.3%), and is statistically significant. Of further significance is that those dates include the four weeks before and the ten weeks after the Fukushima Nuclear Power Plant disaster"
I took a look at the data and as a result I find this article to be a disgrace.

Im not sure why they picked the locations they did, just a handful from a very long list, and why for example they did not look at the data for the entire US region described as 'Pacific'.

If I look at data for the Pacific cities deaths of infants under 1 year of age:

4 weeks ending March 19 2011, there are an average of 23.5 deaths per week
10 weeks ending May 28 2011, there are an average 23.6 deaths per week

Now lets compare to 2010:

4 weeks ending March 20 2010, there are an average of 26.25 deaths per week
10 weeks ending May 29 2010, there are an average of 25.9 deaths per week

Now looking at the 2010 averages for just the cherry-picked cities they used:

4 weeks ending March 20 2010, there are an average of 11 deaths per week
10 weeks ending May 29 2010, there are an average of 12.2 deaths per week

And that 12.2 average is brought down by the fact that during this period 4 weeks of San Jose data is missing. If for example I assume that the number of <1 year deaths for the missing San Jose weeks is just 2 per week, then the average climbs to 13 deaths per week.
SteveElbows
#50
Jun11-11, 02:48 PM
P: 630
Quote Quote by jlduh View Post
I have this table with data it seems from CTBTO measurement network, but as i don't speak japanese i cannot give precisions of where it was measured, i just read the numbers for the various isotopes!

http://www.cpdnp.jp/pdf/110603Takasaki_report_May30.pdf

But this is interesting as you can see that there has been three spikes in the measurements:

- One (the biggest) between March 15 and 16
- One between March 20 and 21 (which fits the "black smoke coming from N3" period)
- One between March 29 and 30
The Japanese report to IAEA makes mention of the March 15th stuff.

http://www.kantei.go.jp/foreign/kan/...chapter_vi.pdf Page VI-3

An air dose rate of about 3 mSv/h was measured near MP-6 at 21:00 on March 14. This rate decreased once but increased again after 06:00 on March 15, and a dose rate of about 12 mSv/h was measured at 09:00 on the same day. In Unit 2, a decrease in D/W pressure was observed due to a wet venting at 21:00 on March 14, and it is estimated that radioactive materials were discharged from Unit 2 because of a blast sound from the unit at around 06:00 on March 15 and a subsequent S/C pressure decrease. At around the same time, however, an explosion occurred in the reactor building of Unit 4, thus a clear distinction cannot be made between them. Since wind often blew from the north in this period, the plume was very likely to have blown to the south, and agencies including the Japan Atomic Energy Agency (JAEA) in Tokai village, Ibaraki prefecture observed a rise in the dose rate and detected radioactive iodine, etc. in the atmosphere.
I have a particular interest in this stuff because early on they were prepared to acknowledge reactor 2 containment damage but not containment damage at other reactors, and also because their estimates of percentage of various substances released into environment seem to have a much wider range for reactor 2 than the others. So I ponder whether reactor 2 may have caused more environmental woe than the others.
ElliotLake
#51
Jun11-11, 09:37 PM
P: 11
SteveElbows: I don't know about the Cali sites, but Portland and Seattle are large seacoast cities and.. Boise is I believe the only one in Idaho where there are sensors in use. Plus, standing under the Rockies, it catches Pacific weather as well. So, seem sensible to me to check those sites. Interpretation of data I couldn't say.
clancy688
#52
Jun12-11, 05:01 PM
P: 546
I think that fits here better:

A discussion in another thread raised the question whether the Hiroshima and Nagasaki contaminations were worse or not.

I searched for the answer and found a very interesting document by the US military:

http://www.dtra.mil/documents/ntpr/r...ATR805512F.pdf

It's dealing with radiation doses for US occupational forces in late 1945 in Nagasaki. On page 58 they calculate surface contamination rates for several isotopes at a location one mile east of and 45 days after the blast. The location was shielded, so there's no neutron activation, only surface deposition.
They get 0.37 uCi/m, or ~14.000 Bq/m Cs-137. In Fukushima, large areas are contaminated with 1.000.000 to 30.000.000 Bq/m Cs-137...

Overall they get 340 uCi/m, which's around 13.000.000 Bq/m, but most of those isotopes are short living ones which are gone after 1-2 years.

So at least for me it looks like the Fukushima contamination is way worse than the Nagasaki bomb contamination. Apparently, the blast produced many short living fission products, but less long lived.

I think that's to be expected. A nuclear reactor's core load fissures over a period of months and creates a hundred or thousand times more energy a Nagasaki sized nuclear bomb releases during that interval.
Which means that there's a hundred or thousand times more fission products which accumulate, especially the long living ones.


But I'd still be interested in more documents regarding the surface contamination of Hiroshima and Nagasaki.


Btw: Don't know if it's been posted before, but the french report linked in the first post is available in english now.

http://www.irsn.fr/EN/news/Documents...H-23052011.pdf
Borek
#53
Jun12-11, 05:21 PM
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Quote Quote by clancy688 View Post
So at least for me it looks like the Fukushima contamination is way worse than the Nagasaki bomb contamination.
Hardly surprising. If not for other reasons, compare mass of the bomb with mass of the fuel in the reactor.
clancy688
#54
Jun12-11, 05:26 PM
P: 546
Quote Quote by Borek View Post
Hardly surprising. If not for other reasons, compare mass of the bomb with mass of the fuel in the reactor.
Apparently it was surprising for a certain user who should know better... that's why I posted it here... ^^;


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