Fukushima Japan earthquake - contamination & consequences outside Fukushima NPP

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Stumbled across this site.

Database on the Research of Radioactive Substances Distribution

http://radb.jaea.go.jp/mapdb/en/
 
How accurate is this video?

https://www.youtube.com/watch?v=3l8TT1dv-PM
 
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How accurate is this video?
It would be good to know the released amount they used for the calculation. Anyway, it might be accurate.

But: please mind the scale! And the used color.
That part is the oldest trick in that book.
 

russ_watters

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Looks reasonable to me, as a representation of how substances dissipate in water. Note the order of magnitude concentrations: after 1 year, the highest concentration (center of the plume) is 1/10,000th the initial concentration and it equalizes at 1/100,000th the initial concentration.

Here's some more detail:
Dilution due to swift horizontal and vertical dispersion in the vicinity of the energetic Kuroshio regime leads to a rapid decrease of radioactivity levels during the first 2 years, with a decline of near-surface peak concentrations to values around 10 Bq m−3 (based on a total input of 10 PBq). The strong lateral dispersion, related to the vigorous eddy fields in the mid-latitude western Pacific, appears significantly under-estimated in the non-eddying (0.5°) model version. (ii) The subsequent pace of dilution is strongly reduced, owing to the eastward advection of the main tracer cloud towards the much less energetic areas of the central and eastern North Pacific. (iii) The magnitude of additional peak radioactivity should drop to values comparable to the pre-Fukushima levels after 6–9 years (i.e. total peak concentrations would then have declined below twice pre-Fukushima levels).
http://www.washingtonsblog.com/2012/07/radiation-in-west-coast-of-north-america-could-be-10-times-higher-than-japan.html
 
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Looks reasonable to me, as a representation of how substances dissipate in water. Note the order of magnitude concentrations: after 1 year, the highest concentration (center of the plume) is 1/10,000th the initial concentration and it equalizes at 1/100,000th the initial concentration.

Here's some more detail:

http://www.washingtonsblog.com/2012/07/radiation-in-west-coast-of-north-america-could-be-10-times-higher-than-japan.html
It's worth reading the original study; the HTML version includes a link to the entire video. Also, Fig.7 sums up their predicted changes pretty clearly:

Model simulations on the long-term dispersal of 137Cs released into the Pacific Ocean off Fukushima
http://iopscience.iop.org/1748-9326/7/3/034004/article?v_showaffiliations=yes

Pre-Fuku background in the Pacific was about 2 Bq/m3 (higher in the North Pacific; see attached map). The authors state:

"Tentatively assuming a value of 10 PBq for the net 137Cs input during the first weeks after the Fukushima incident, the simulation suggests a rapid dilution of peak radioactivity values to about 10 Bq/m3 during the first two years, followed by a gradual decline to 1–2 Bq/m3 over the next 4–7 years. The total peak radioactivity levels would then still be about twice the pre-Fukushima values."


Here's a more recent paper with slightly different estimates, but in the same general ballpark (within an order of magnitude or so).

Multi-decadal projections of surface and interior pathways of the Fukushima Cesium-137 radioactive plume
http://www.sciencedirect.com/science/article/pii/S096706371300112X

The attached map is from the Woods Hole website. I think it helps put the expected increases in the Pacific due to Fukushima in perspective.:

http://www.whoi.edu/page.do?pid=83397&tid=3622&cid=94989

The biggest take-away for me is that while the simulations by Behrens et al (peaks of about 3-4Bq/m3 total) and by Povinec, Aoyama et al (peaks of about 10-30Bq/m3 total), show much lower Cs137 levels in coming years near Hawaii and the West Coast than the Irish Sea, Baltic, or Black Sea in 1990, the extent of ocean affected will be vastly bigger than any of these. Along with the important caveat that these are simulations, and nature could surprise us unpleasantly.
 

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... nature could surprise us unpleasantly.
Thanks for the simulations.

As I know Cs tends to stick in the mud, and only limited amount remains free for dilution.
For long term it would mean that:
- the measurable level in the ocean might be lower than expected
- but even with lower levels in the waters every fish from around Fukushima should be checked because sporadically there will be always some fish with high levels of Cs.
 
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Thanks for the simulations.

As I know Cs tends to stick in the mud, and only limited amount remains free for dilution.
For long term it would mean that:
- the measurable level in the ocean might be lower than expected
- but even with lower levels in the waters every fish from around Fukushima should be checked because sporadically there will be always some fish with high levels of Cs.
Rive,

I definitely agree that monitoring of contamination in fish caught of Japan needs to be continued for the long term and improved. Maybe the least predictable aspect is what could happen in shallow water off coastlines like Hawaii, Aleutians, or the West Coast. Maybe nothing above the barely detectable level, but maybe we'll see some kind of "warm spots" (not enough to be called "hot spots").
 

etudiant

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People eat fish from the 125 Bq/m**3 Baltic every day and in canned form it is offered for sale in the US.
Ditto the 55 Bq/m**3 Irish Sea, home of 'Organic Salmon'.
Why are these obvious targets not getting more intensive scrutiny? Better PR management than TEPCO?
 
Not to mention that K-40 contributes ~15 kBq/m3 (yes, that is "kilo"!) in seawater.
 
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Why are these obvious targets not getting more intensive scrutiny? Better PR management than TEPCO?
I don't know about those.

But as long as I followed the sampling, there was always some fish with excess Cs values - mostly species which are:
- predators
- likes dead flesh
- living close to/on the seabed.

So I think that mud is still dangerous (or at least: what living on it can be above the limits) and it'll remain so in the next centuries even if the Cs in the seawater is low.
 
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tsutsuji

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http://www3.nhk.or.jp/news/genpatsu-fukushima/20130925/index.html Rice was harvested for the first time since 2010 in Hirono, 30 km south of the plant, and 100% testing has started. It concerns 110 Ha or half of Hirono's rice fields.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20130925/0637_ryo.html So-called test-fishing was started again (after the suspention due to the plant's contaminated water problem) in Fukushima prefecture, with 25 boats leaving Matsukawaura port, Soma city, early in the morning on 25 September. Fishing is restricted to 16 species and depths not exceeding 150 m, in locations farther than 50 km from the plant.
 
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tsutsuji

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http://www3.nhk.or.jp/news/genpatsu-fukushima/20131001/1520_zengyoren.html A representative of Japan Fisheries Cooperatives Zengyoren is visiting the South Korean embassador in Tokyo today to ask South Korea to lift its import ban of Japanese fish.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20131001/index.html Decontamination work was started today for the first time inside the "hard to come back area", where the radiation is above 50 mSv/year. The work is started as a test in 5 locations in Namie and in Futaba. The test will be performed until the end of this year, with the aim of producing data covering efficiency, cost, and worker exposure management.
 
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No decision yet on disposal sites for contaminated waste in 5 prefecture

A cattle farmer with contaminated rice straw he stores at his farm in Tome, Miyagi Prefecture, on Sept. 20
Why should it be stored?
You can mix the "dirty" with clean straw.
Furthermore, the straw is obviously contaminated mainly cesium.
It is necessary to feed the cattle 6 months of clean straw (after dirty)
In meat, the cesium will not.
* In the past (after Chernobyl) have done so.
Will radioactive manure.
This is an excellent fertilizer for sunflower and rapeseed
 
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Why should it be stored?
You can mix the "dirty" with clean straw.
Is there a serious shortage of straw (or storage space) in the area?

Even that Cs is not all that dangerous, it should not be there. If there isn't a serious reason to let it back to the environment then it should be kept safe. Especially if it costs practically nothing.
 
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Because it is not the Soviet Union, where government can ignore its people opinion and health.
I think you exaggerate somewhat.
It is a scientific fact does not correlate with the political system.
Rive
Is there a serious shortage of straw (or storage space) in the area?
And if there was a fire during the retention period?
 
Is there a serious shortage of straw (or storage space) in the area?

Even that Cs is not all that dangerous, it should not be there. If there isn't a serious reason to let it back to the environment then it should be kept safe. Especially if it costs practically nothing.
Looks like some unwarranted paranoia is at work.

It's *Japan*.

Japan IIRC is quite active in creating new land offshore (for airports and such). This requires LARGE amounts of material to be dumped.

I would imagine that all this moderately Cs-137-contaminated material, if properly immobilized, can safely be put into the lower layers of such artificial islands.

Yet, apparently it is not done. I guess because public gets hysterical every time words "contaminated" and "Fukushima" are uttered.
 

tsutsuji

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http://www3.nhk.or.jp/news/genpatsu-fukushima/20131011/index.html Cesium was detected for the first time in the sea outside the port on 8 October 2013 with 1.4 Bq/l of Cs-137. This is below the World Health Organization's 10Bq/l limit for drinking water. On 10 October, the cesium concentration in the same location was below detection limit.

http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/2013/images/2tb-east_13101002-e.pdf Detailed Analysis Results in the Port of Fukushima Daiichi NPS [8 October]
http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/2013/images/2tb-east_13101003-e.pdf Detailed Analysis Results in the Port of Fukushima Daiichi NPS [10 October]
 

tsutsuji

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http://www3.nhk.or.jp/news/genpatsu-fukushima/20131014/index.html On 14 October, South Korean foreign minister Yun Byung-Se said at the South Korean Parliament that South Korean representatives would take part to the joint IAEA-Japan sea water radiation monitoring.

http://english.chosun.com/site/data/html_dir/2013/10/10/2013101002044.html (10 October 2013)

The Japanese government will include Korean experts in an international investigatory team to check fisheries products for radioactive contamination from the crippled Fukushima nuclear power plant.
 
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IAEA reorients the goals of japanese government for decontamination targets: protect populations is good, but "educate" people is better (and easier... maybe?)

http://ajw.asahi.com/article/0311dis...AJ201310230076 [Broken]

Well...
 
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IAEA reorients the goals of japanese government for decontamination targets: protect populations is good, but "educate" people is better (and easier... maybe?)
In my opinion, better education is one the best things than can be done in general, not only in relation to this accident.

In relation with radiation and accidents, it would be wonderful if people would know such facts as:

What is the typical level of natural radiation in a human body? In seawater? Which isotopes contribute to that?
What is the typical natural radiation background level? What is its typical variation?

(the knowledge of above facts would allow people to meaningfully interpret news items like "fish with 100 Bq/kg of Cs-137")

Which isotopes are most mobile after a nuclear accident?
What are their modes of decay and half-lives?
What are the measures to limit their intake?
 

etudiant

Gold Member
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In my opinion, better education is one the best things than can be done in general, not only in relation to this accident.

In relation with radiation and accidents, it would be wonderful if people would know such facts as:

What is the typical level of natural radiation in a human body? In seawater? Which isotopes contribute to that?
What is the typical natural radiation background level? What is its typical variation?

(the knowledge of above facts would allow people to meaningfully interpret news items like "fish with 100 Bq/kg of Cs-137")

Which isotopes are most mobile after a nuclear accident?
What are their modes of decay and half-lives?
What are the measures to limit their intake?
That would require a measure of scientific literacy beyond what current education provides.
Most people would be shocked to hear that there is a natural radiation background.

Moreover, the language of nuclear measurement aims at precision, not intelligibility.
A hundred anything seems large, although when measuring Bq/kg, it is about the radioactivity of granite. But people get very alarmed about anything involving radiation, probably because truth has been spun or disguised too many times under various pretexts.
At this point, neither the governments nor the industry have credibility, so there is even a reluctance to learn what are perceived to be lies. Not good for the future of the discipline, imho.
 
That would require a measure of scientific literacy beyond what current education provides.
Most people would be shocked to hear that there is a natural radiation background.

Moreover, the language of nuclear measurement aims at precision, not intelligibility.
A hundred anything seems large, although when measuring Bq/kg, it is about the radioactivity of granite. But people get very alarmed about anything involving radiation, probably because truth has been spun or disguised too many times under various pretexts.
At this point, neither the governments nor the industry have credibility, so there is even a reluctance to learn what are perceived to be lies. Not good for the future of the discipline, imho.
I think you are selling the general population short here, there are very many people that would like the facts on radiation and the various ways of measuring it and reporting it.

Further I belive most people are aware of natural background radiation, but we want to know how much of what is considered "normal" now is a result of atmospheric testing and NPP accidents.

When you say that when measuring 100 Bq/kg is about the radioactivity of granite you ignore the fact that most organisms or intelligent people do not ingest granite nor will bio accumalation going up the food chain further concentrate it, unlike cesium, strontium etc.

I agree that the governments and indusry have lost all credibiity with the general population and for good reasons, we have been lied to far too often!
 

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