Fukushima Japan earthquake - contamination & consequences outside Fukushima NPP

[LabratSR]

Stumbled across this site.

Database on the Research of Radioactive Substances Distribution

http://radb.jaea.go.jp/mapdb/en/

 

[Greg Bernhardt]

How accurate is this video?

https://www.youtube.com/watch?v=3l8TT1dv-PM

 

[Rive]

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]

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...rica-could-be-10-times-higher-than-japan.html

 

[Azby]

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...rica-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.

 

[Rive]

... 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.

 

[Azby]

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]

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?

 

[nikkkom]

Not to mention that K-40 contributes ~15 kBq/m3 (yes, that is "kilo"!) in seawater.

 

[Rive]

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.

 

[tsutsuji]

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.

 

[zapperzero]

According to ex-skf blog, the so-called "trial" fishing is actual fishing, the fish will get sold.
http://ex-skf.blogspot.ro/2013/09/trial-fishing-in-iwaki-city-in.html

 

[tsutsuji]

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.

 

[a.ua.]

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

 

[nikkkom]

No decision yet on disposal sites for contaminated waste in 5 prefecture

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.

Because it is not the Soviet Union, where government can ignore its people opinion and health.

 

[Rive]

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.

 

[a.ua.]

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?

 

[nikkkom]

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]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20131005/index.html Japan is taking the Korean fish import ban (covering fish caught in eight Japanese prefectures) to the World Trade Organisation.

 

[tsutsuji]

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]

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.

 

[jlduh]

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

Well...

 

[nikkkom]

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]

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.

 

[jadair1]

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 believe 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!

 

[Gary7]

I think you may both be right; there is a desire to know more, but as I found with Fukushima, the more I learned, the more I discovered the limits to my understanding of nuclear physics, and the more I could see how easily people's perceptions could be swayed by shonky science and politically-biased studies. It is a daunting science if you are trying to study it as an amateur, and the task is made more difficult by the distractions of Michio Kaku and Arnie Gundersen, and the conspiracy theories that seemed to pop up like mushrooms. Even in the brief exchange above you can see the gulf that exists and is exploited by both sides. Is 100 bq in a tuna sandwich an existential threat? One side says 100 bq is less radiation exposure than you would get in a dental x-ray, and the other side says "yes, but you don't eat the x-ray machine", and no one becomes the wiser, they merely retreat into their entrenched camps of pro or anti nuclear.

For the anti-nuclear movement, nuclear science is in itself an original sin that taints every study, every observation, every epidemiological investigation, and therefore cannot be trusted, or worse, is part of a conspiracy. Conspiracy theories are attractive because they require less effort, and validate some human desire to believe that superior powers are working to manipulate you, and so merely believing in a conspiracy theory becomes an act of defiance, and is appealing to those who can't be bothered learning the difference between alpha, gamma, or beta radiation, or the esoterica of decay heat produced by a nuclear fuel bundle. And yes, both government and industry have kicked so many own goals that they are deserving of the suspicion with which the general public treats them.

By its nature, nuclear science defies easy understanding. The science is "dumbed down" for the benefit of people with an ever-shrinking attention span. Analogies of x-rays, jet travel, bananas, granite counter-tops, and the like are used, and are then in turn deconstructed to push a counter-argument. The UC Berkely Radiological Air and Water Monitoring forum was completely hijacked by this issue, to the detriment of all I would say.

It comes down to a question of statistics and probability. If people knew that, for example, 7% of the background radiation came from atmospheric nuclear testing, would it be a meaningful statistic? No, of course not. It only becomes mildly meaningful if you have the patience to delve into the science and the debate of the Linear Non-Threshhold model. If you've made it this far, however, your dread of nuclear power has been largely ameliorated.

 

[jadair1]

Here is a recent quote from the South China Morning Post:

"Conditions in the unit 4 pool, 100 feet from the ground, are perilous, and if any two of the rods touch it could cause a nuclear reaction that would be uncontrollable," said Perrow.

"The radiation emitted from all these rods, if they are not continually cool and kept separate, would require the evacuation of surrounding areas including Tokyo," he said. "Because of the radiation at the site the 6,375 rods in the common storage pool could not be continuously cooled; they would fission and all of humanity will be threatened, for thousands of years."

I do not for a moment doubt that the conditions are perilous and that some of the rods will be distorted but I am skeptical that two of the rods touching "could" cause a nuclear reaction, I think the probability of that is so low it would be almost infinitesimal even if they touched for a significant time.

On the other hand I believe the chance of a fuel rod breaking while attempting to remove it is fairly significant and I would like to know what the consequences of this would be.

Also I would like to know how hot these rods are, some have been in the pool for many years and the hottest ones for around three years or so.

Is it true that their radioactivity increases for years after they are removed from the reactor? This does not make sense to me as I have also heard that they only need to be cooled for approximately 5 years before they are safe to put into dry cask storage.

There is so much disinformation out there it is getting difficult to separate the real information from the noise.

I am very interested in these things since my wife and I have both been very sick with unkown ailments since the early summer of 2011, we are on Southern Vancouver Island and got hit fairly hard with the fallout from Fukushima that spring.

On the bright side our Sweet William Carnations that normally grow to be only 6 - 8" tall grew to 3' tall, quite incredible for anyone that knows flowers. And every year since they have grown the same, our neighbors have been asking for seeds as they've never seen the like before!

Is this all a coincidence, perhaps so, but the jet stream was comming from Fukushima to Van. Isle when the reactors blew and we had a lot of rain for a few days after the explosions and we were working outside preping the gardens during this time.

 

[Rive]

stuff

It's just fearmongering. U4 pool conditions are not perfect, but also not terrible. They should be able to manage it.

It's a kind of thumb rule: if a source is continuously jumping around U4 pool then there is a good chance that it's just crap. U3 pool conditions - those are terrible: good chance that there are many (!) broken rods, with definitely damaged geometry and racks, with a heavy machinery is still lying on the top of the heap, and yet, there is no sign of ongoing recriticality.

About your questions:
- some broken rods would pollute the water in the pool, but it's very unlikely that they would cause any further problem.
- a rod while is underwater is not 'hot'. They has a heat output, continuously falling with time. This heat is removed by the water. If the heat is low enough to be removed by just air, then they can be extracted from the water. This is the 5 year limit you mentioned, however it's not a hard limit. Especially, because these rods will not go to dry casks, they will be moved to the common pool.
- the radioactivity of the used nuclear fuel is continuously falling with time.

Ps.: about your flowers and so: it's just coincidence. Our flowers have also changed, but some compost did the trick. However, if you want to control your fear, get a cheap dosimeter somewhere and check.

Ps2.: it was letucce season (spring) when we got some stuff from Chernobyl (as we are relatively close to the site and there was some fallout here), but nothing could be seen on the vegetables that year. I don't think that your flowers would be more sensitive.

 

[jadair1]

The problem with the U4 pool is that it had a "hot" core that had just been taken out of the reactor a short time before the earthquake.

It is also speculated that it burned for several days which if true would imply that the condition of some of the rods would be indeed less than perfect.

It's just fearmongering. U4 pool conditions are not perfect, but also not terrible. They should be able to manage it.

It's a kind of thumb rule: if a source is continuously jumping around U4 pool then there is a good chance that it's just crap. U3 pool conditions - those are terrible: good chance that there are many (!) broken rods, with definitely damaged geometry and racks, with a heavy machinery is still lying on the top of the heap, and yet, there is no sign of ongoing recriticality.

How long ago was the last core put into U3, and when was the last time someone went into inspect it?

I do believe there are signs of criticality ongoing, are they not finding signs of short half life isotypes these days?

About your questions:
- some broken rods would pollute the water in the pool, but it's very unlikely that they would cause any further problem.

Exactely what I thought.

- a rod while is underwater is not 'hot'. They has a heat output, continuously falling with time. This heat is removed by the water. If the heat is low enough to be removed by just air, then they can be extracted from the water. This is the 5 year limit you mentioned, however it's not a hard limit. Especially, because these rods will not go to dry casks, they will be moved to the common pool.

Yes I understand this but if they are not kept submerged then they will get hot and burn, what I meant I guess with this question is not how hot they are per say, but how radioactive they still are?

If they were to drop one of the rods outside containment what would the consequences be, that is what I meant by how hot are they.

- the radioactivity of the used nuclear fuel is continuously falling with time.

Thank you, this is what I thought but some reports I've read say the radioctivity of the rods increase for 250,000 years which I thought to be ludicruse. Unless there was fissioning happening continuosly the rods would decay at their component materials half lifes once taken out of the reactor.

Ps.: about your flowers and so: it's just coincidence. Our flowers have also changed, but some compost did the trick. However, if you want to control your fear, get a cheap dosimeter somewhere and check.

Not scared, I already died once just over 5 years ago and it wasn't a big deal!

Just wondering, and I did not need to add any compost to any of my gardens, when I put them in 7 years ago I used plenty of Sheep, Cow and Chicken Manure, haven't needed to touch the soil since.

Ps2.: it was letucce season (spring) when we got some stuff from Chernobyl (as we are relatively close to the site and there was some fallout here), but nothing could be seen on the vegetables that year. I don't think that your flowers would be more sensitive.

It's fallout of course you wouldn't see anything, what would there be to see?

Also relative closeness to a Nuclear accident does not equate to how much fallout you recive, Vancouver Island and many other areas in North America got more fallout than many areas In Japan. The Jet stream carried it here.Most of my plants were not affected and grew normally but the Sweet Williams went insane, I have no idea why.

 

[nikkkom]

but we want to know how much of what is considered "normal" now is a result of atmospheric testing and NPP accidents.

Your "want to know" isn't strong at all.
Who is banning you from reading, say, Wikipedia on this subject?

 

[nikkkom]

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.

Gosh.
Human body's natural radiation from K-40 and C-14 is around 70 Bq/kg.
There are some food products (nuts) with up to 400 Bq/kg of K-40.

This seems to confirm that general public is in dire need of educating.

 

[nikkkom]

By its nature, nuclear science defies easy understanding.

I don't think so.
I can summarize main facts about radiation, both natural and man-made, bombs, reactors and their accidents, into about a single page of text.

The difficulty lies in delivering this information to people.

Why news articles about "fish with N Bq/kg of Caesium-137 found" never accompanied with "for reference: seawater's natural radioactivity is ...; typical fish meat natural radioactivity is ..." snippets?

 

[etudiant]

I don't think so.
I can summarize main facts about radiation, both natural and man-made, bombs, reactors and their accidents, into about a single page of text.

The difficulty lies in delivering this information to people.

Why news articles about "fish with N Bq/kg of Caesium-137 found" never accompanied with "for reference: seawater's natural radioactivity is ...; typical fish meat natural radioactivity is ..." snippets?

The XKCD cartoon strip (much read among IT geeks) had an excellent radiation on a single page summary. It includes some relevant background radiation data. See:
http://xkcd.com/radiation/

It was well enough received that the author placed it into the public domain.

 

[jadair1]

The XKCD cartoon strip (much read among IT geeks) had an excellent radiation on a single page summary. It includes some relevant background radiation data. See:
http://xkcd.com/radiation/

It was well enough received that the author placed it into the public domain.

Thank you for that a very well formated and simple explanation.

I do not neccesarily trust Wikapedia as a source of information.

That is why I am here, to get the opinions of experts.

 

[nikkkom]

I do not neccesarily trust Wikapedia as a source of information.

Despite oft-repeated "Wikipedia is unreliable", it is a good starting point, especially on non-controversial subjects (why would anyone lie about e.g. half-life of I-131?). Wiki also has external links for more information, which can be used to verify the data.

 

[jlduh]

Cesium contamination levels up around 10 times at the bottom of the ocean in some points 1 to 3 km around Fukushima site in September, trend to be followed up:

http://fukushima-diary.com/2013/10/...-spiked-up-this-september-over-10-times-much/

http://www.tepco.co.jp/nu/fukushima-np/f1/smp/2013/images/ocean_soil_131025-j.pdf

 

[zapperzero]

http://www.scientificamerican.com/a...prove-plan-to-release-groundwater-from-plant/
Fisheries association approve plan for a groundwater bypass. As I understand it, the water is captured in drains uphill of the plant and dumped into the sea and as such it is only very slightly contaminated anyway.

 

[a.ua.]

http://www.asyura.us/bigdata/up1/source/22098.jpg
http://ex-skf.blogspot.com/2014/04/happy-april-fools-day-residents-back-in.html

 

[F X]

Anyone know if this article is accurate?

http://www.vice.com/read/no-one-wants-you-to-know-how-bad-fukushima-might-still-be-666

 

[Rive]

Anyone know if this article is accurate?

http://www.vice.com/read/no-one-wants-you-to-know-how-bad-fukushima-might-still-be-666

As I see that article is accurate in some details: but as the accurate pieces are seriously contaminated with many fear-mongering and lots of inaccurate speculation, it's inaccurate in the big picture it draws.

The author carefully selects the pieces of information fits with his preconception. That's not the way to write accurate articles.

 

[etudiant]

It seems that apart from the problematic subdrain freezing effort, TEPCO has made substantial progress in sealing off the site
http://www.world-nuclear-news.org/RS-Additional-measures-for-Fukushima-water-management-1408144.html

Of course the steel barrier only addresses the ocean side, so more needs to be done, but it has gotten very little
public attention. Is it a useful step or a waste?

 

[mheslep]

Anyone know if this article is accurate?

http://www.vice.com/read/no-one-wants-you-to-know-how-bad-fukushima-might-still-be-666

When I asked past Nobel Peace Prize nominee Dr. Helen Caldicott these questions, she was quick to respond: “Because money matters more than people.”

nominee Caldicott has spoken. The lure of money and fame apply to others, not her.

No the article can not be entirely accurate.

 

[Astronuc]

Caldicott's comment, “The problem is that TEPCO has hardly invited in the international community to help to try and solve the problem,” says Dr. Caldicott. “A huge company like [Florida-based engineering group] Bechtol, which makes reactors and is a very good engineering company, should have been invited in by the Japanese government to try and propose a way to deal with these problems in an engineering fashion,” or the statement attributed to her is incorrect.

Bechtel is a civil engineering and construction company based in San Francisco, although they have branches/offices in various locations. They do the civil/structural works at nuclear power plants, other power plants and process plants. They do not make reactors.

TEPCO has had foreign experts providing advice and assistance, although I do not know the specific outcomes of those interactions.

 

[Gary7]

I'm trying to understand a bit more about fission products of Fukushima Daiichi, their distribution as a result of the accident, etc. Specifically, I'm struggling to understand the details of Cesium 137 and Cesium 135.

The ANL Human Health Fact Sheet regarding Cesium (October 2001) mentions that both Cesium 135 and 137 are produced in relatively high yields of 7% and 6% (respectively). Yet Cesium 135 is rarely mentioned in soil or water analyses.

My questions are;
1. Shouldn't there be equally large amounts of Cesium 135 in the environment as there are of Cesium 137?
2. If so, does the comparatively low specific activity and energy yield of Cesium 135 mitigate its health risk to the point where it is negligible compared to the other radionuclides?
3. Or, is it the decay of Cesium 137 into Barium 137m that makes Cesium 137 so dangerous? (Again, meaning the health risk of Cesium 135 is negligible by comparison).

Any help in sorting this out would be appreciated.

 

[Gary7]

Since I'm in a confessional mood, I guess I should also admit I don't really understand how the various isotopes of cesium are produced: is it correct to say that Cesium 135 is the decay/daughter product of Xe135 (which itself is a fission product of U235), and that Cesium 137 and 134 are the direct fission products of U235?

 

[nikkkom]

I'm trying to understand a bit more about fission products of Fukushima Daiichi, their distribution as a result of the accident, etc. Specifically, I'm struggling to understand the details of Cesium 137 and Cesium 135.

The ANL Human Health Fact Sheet regarding Cesium (October 2001) mentions that both Cesium 135 and 137 are produced in relatively high yields of 7% and 6% (respectively). Yet Cesium 135 is rarely mentioned in soil or water analyses.

My questions are;
1. Shouldn't there be equally large amounts of Cesium 135 in the environment as there are of Cesium 137?
2. If so, does the comparatively low specific activity and energy yield of Cesium 135 mitigate its health risk to the point where it is negligible compared to the other radionuclides?
3. Or, is it the decay of Cesium 137 into Barium 137m that makes Cesium 137 so dangerous? (Again, meaning the health risk of Cesium 135 is negligible by comparison).

1 Yes
2 Yes. Cs135 specific activity is ~100 thousand times less than Cs137.
3 No, mainly it's reason #2 why Cs135 gets far less attention

 

[mheslep]

1. Shouldn't there be equally large amounts of Cesium 135 in the environment as there are of Cesium 137?

After 15 yrs, half the 137 will be gone. Not so the 135.

 

[Gary7]

Shouldn't that be 30 years?

 

[mheslep]

Shouldn't that be 30 years?

Yes, sorry.

 

[Astronuc]

Greenpeace - Radiation Along Fukushima Rivers Up to 200 Times Higher Than Pacific Ocean Seabed
http://www.ecowatch.com/radiation-f...her-than-pacific-ocean-seabed-1937971722.html

Riverbank sediment samples taken along the Niida River in Minami Soma, measured as high as 29,800 Bq/kg for radiocaesium (Cs-134 and 137). The Niida samples were taken where there are no restrictions on people living, as were other river samples. At the estuary of the Abukuma River in Miyagi prefecture, which lies more than 90km north of the Fukushima Daiichi plant, levels measured in sediment samples were as high as 6,500 Bq/kg.

It would be nice to have independent confirmation, but it makes sense that Cs (and other radionuclides) would find their way to rivers where they would concentrate in the sediment. Cs is more soluble in seawater, so it would be diluted much more rapidly.