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Japan earthquake - contamination & consequences outside Fukushima NPP

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tsutsuji
#595
Nov20-12, 01:14 PM
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Last year the following reports were completed

Quote Quote by tsutsuji View Post

Miyagi:
http://mainichi.jp/area/miyagi/news/...40073000c.html A study of Miyagi prefecture rivers and lake has been released by the ministry of environment. Cesium was found in water only in one out of 138 tested locations, with 3Bq/kg. 11,000 Bq/kg was found in the mud at the bottom of Nanakita river in Sendai. As a whole, 21 locations were found with river mud above 1000 Bq/kg. The radiation is comparatively higher close to river mouths.

http://www.env.go.jp/jishin/monitori...pw111216-1.pdf Miyagi prefecture river monitoring results

Tochigi:
http://sankei.jp.msn.com/region/news...2120004-n1.htm The ministry of environment released a Tochigi prefecture river and lake survey. In one location 1 Bq/l was found in water. 4900 Bq/kg was found in river bottom mud in Nikko. They also checked the earth in areas surrounding rivers, and found 9400 Bq/kg of Cs137 in Nasu.

http://www.env.go.jp/jishin/monitori...pw111216-2.pdf Tochigi prefecture river monitoring results
Updates are done periodically : http://www.env.go.jp/jishin/monitori...ults_r-pw.html

http://www.env.go.jp/jishin/monitori...pw121011-1.pdf This is the last one, for Fukushima prefecture rivers (11 October 2012). Radiation doses in river water : All Cs-137 values were between undetected and 3 Bq/l ; Cs-134 between undetected and 2 Bq/l. In river mud, Cs-137 goes up to 37,000 Bq/kg (dry mud).
etudiant
#596
Nov20-12, 07:54 PM
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Quote Quote by tsutsuji View Post
Last year the following reports were completed



Updates are done periodically : http://www.env.go.jp/jishin/monitori...ults_r-pw.html

http://www.env.go.jp/jishin/monitori...pw121011-1.pdf This is the last one, for Fukushima prefecture rivers (11 October 2012). Radiation doses in river water : All Cs-137 values were between undetected and 3 Bq/l ; Cs-134 between undetected and 2 Bq/l. In river mud, Cs-137 goes up to 37,000 Bq/kg (dry mud).
That makes sense. The cesium is mostly caught in the river mud and forest soil, although some is reextracted by the tree roots. The radiation scar on this part of Japan is consequently a long lived feature, rather than something that will wash away over a few seasons.
Still it also suggests that while people from the area should be careful about eating the mushrooms and burning the wood, they can live pretty normally otherwise.
Just hope this does not give the area's inhabitants a stigma.
tsutsuji
#597
Nov21-12, 07:05 PM
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http://www3.nhk.or.jp/news/genpatsu-...120/index.html The NRA had a meeting on 20 November 2012 and decided to respond to inhabitants' unsatisfaction concerning health surveys. A 5 member Study team including Fukushima medical college professor(s) will review how surveys are done, and make proposals within this year about how to respond to long term low level radiation exposure. The study team will meet 3 or 4 times this month and next month. NRA chairman Shunichi Tanaka says "as there is no plan about long term low radiation exposure, inhabitants are expressing unsatisfaction and unsecurity. We want to build up proposals that respond to those voices".
Rive
#598
Nov22-12, 02:55 AM
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Quote Quote by etudiant View Post
Still it also suggests that while people from the area should be careful about eating the mushrooms and burning the wood, they can live pretty normally otherwise.
I think it'll be a bit more complicated than that. After seasonal floods the flood-area of the rivers will always be re-contaminated and as it dries it'll produce a regular increase of fallout through the winds -> new hotspots around roads, roof-drainages and so on.

It'll require a continuous monitoring and cleanup operations to keep the limits.
Rive
#599
Nov22-12, 02:58 AM
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Quote Quote by tsutsuji View Post
http://www3.nhk.or.jp/news/genpatsu-...120/index.html The NRA had a meeting on 20 November 2012 and decided to respond to inhabitants' unsatisfaction concerning health surveys. A 5 member Study team including Fukushima medical college professor(s) will review how surveys are done, and make proposals within this year about how to respond to long term low level radiation exposure. The study team will meet 3 or 4 times this month and next month. NRA chairman Shunichi Tanaka says "as there is no plan about long term low radiation exposure, inhabitants are expressing unsatisfaction and unsecurity. We want to build up proposals that respond to those voices".
Tsutsuji, do you have anything about the change of (preventive) Potassium iodide consumption over Japan?
tsutsuji
#600
Nov23-12, 05:28 AM
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http://www3.nhk.or.jp/news/genpatsu-...122/index.html The NRA's evacuation criteria study team composed of external experts started the main discussions on 22 November. On 22 November, they confirmed that they want to create Japan's own decision making standard regarding when to take iodine pills, based on the IAEA's standards as a reference, on the plant status, and on measured values. Fukushima Daiichi was victim of a manifold disaster including earthquake, tsunami, and measurements were not sufficient. One expert says "In addition to monitoring, it is suggested to make practical use of predictive systems".The study team will reach conclusions by the end of this year, so that local government bodies can prepare evacuation plans by the end of next March.
tsutsuji
#601
Nov29-12, 03:34 AM
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http://www3.nhk.or.jp/news/genpatsu-...129/index.html The government is starting an investigation over the fact that more than half of the so-called earthquake-related deaths, which means people dying when health deteriorates during prolonged evacuation life, or 1100 deaths, are located in Fukushima prefecture. Conducting hearings of inhabitants and local governments, they will check if the evacuation and government help after the nuclear accident were appropriate. The results of the investigation are expected next autumn. A preparatory meeting was held at the Reconstruction agency on 29 November. Reconstruction minister Hirano says "Several kinds of inspections have been done, but we still lack a unified survey. Information such as who gave the evacuation order, in which situation, is still not clear. We want to record the fact relationships, and to learn lessons from those."
zapperzero
#602
Nov29-12, 05:57 AM
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Quote Quote by tsutsuji View Post
http://www3.nhk.or.jp/news/genpatsu-...122/index.html The NRA's evacuation criteria study team composed of external experts started the main discussions on 22 November. On 22 November, they confirmed that they want to create Japan's own decision making standard regarding when to take iodine pills, based on the IAEA's standards as a reference, on the plant status, and on measured values. Fukushima Daiichi was victim of a manifold disaster including earthquake, tsunami, and measurements were not sufficient. One expert says "In addition to monitoring, it is suggested to make practical use of predictive systems".The study team will reach conclusions by the end of this year, so that local government bodies can prepare evacuation plans by the end of next March.
Is all this implying that there were previously no such guidelines and no such system in place? Isn't this the exact kind of thing that the IAEA is supposed to concern itself with?
tsutsuji
#603
Nov30-12, 07:41 AM
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At some point, the US embassy in Japan issued an evacuation order/advice to leave the 50 miles (80 km) range around the plant. This included Fukushima City and Koriyama, the two largest cities in Fukushima Prefecture. This illustrates the fact that there is not a worldwide consensus on what people should do, upon which criteria, when this kind of event happens.
tsutsuji
#604
Dec1-12, 09:20 AM
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http://www3.nhk.or.jp/news/genpatsu-...0/1935_hp.html The ministry of Environment is starting a new website providing details on the decontamination progress status in each town or village. Where decontamination is performed under the direct responsibility of the national government, it is possible to find on maps the areas where decontamination has been started, and to access the radiation data before and after decontamination. Progress status of decontamination performed by local government bodies is also available.

http://josen.env.go.jp/ The new website.

http://josen.env.go.jp/area/details/...aha_h23_01.pdf For example, this is a report about the decontamination results around the town hall in Naraha town, with the radiation values before and after displayed on maps.
zapperzero
#605
Dec3-12, 01:00 AM
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Quote Quote by tsutsuji View Post
there is not a worldwide consensus on what people should do, upon which criteria, when this kind of event happens.
Certainly there isn't a consensus on what exactly to do in a particular scenario. I would have expected the IAEA to be much more serious about the existence and applicability of SAMGs, radioprotection and evacuation plans in general.
nikkkom
#606
Dec3-12, 02:20 AM
P: 595
Quote Quote by etudiant View Post
Still, a three year half life is only a tenth of the actual Cs 137 half life, so the recycling is only about 10%. Presumably the other 90% are swept away to the sea in the water flows.
Guys, please remember that Chernobyl exists. Use data from there.

IIRC in Chernobyl it was found that Cs is essentially trapped by forests, washout is slow.

The pine trees growing over trenches of buried Red Forest still experience growth deformities, not surprising considering that they have ~1 MBq/kg in their wood...
zapperzero
#607
Dec6-12, 03:51 AM
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http://rpd.oxfordjournals.org/conten...cs320.abstract
EARLY IN SITU MEASUREMENT OF RADIOACTIVE FALLOUT IN FUKUSHIMA CITY DUE TO FUKUSHIMA DAIICHI NUCLEAR ACCIDENT -

Masashi Takada and
Toshikazu Suzuki

Using a high-purity germanium detector, both indoor and outdoor radionuclides that had deposited 1.5 d after the radioactive fallout events in the city of Fukushima were experimentally measured. Eleven artificial (131I, 132I, 134Cs, 136Cs, 137Cs, 129Te, 129mTe, 131mTe, 132Te, 140La and 99mTc) and 5 natural radionuclides were identified. Total air kerma rates were mainly due to 132I, 134Cs and 136Cs from 4 to 6 µGy/h at a 7.5-cm height from the ground. Radioactive contamination on the ground was contributed by 132I and 132Te, from 330 to 420 Bq/cm2. In a worst-case scenario, the maximum skin dose rates were estimated to be from 520 to 670 µGy/h. Effective dose rates were evaluated to be 10 to 15 µSv/h and reached 17.9 µSv/h at 4 a.m. on 16 March. In the effective dose rates, 132I, 134Cs and 132Te were the main contributors. Our measurements are useful for estimating dose levels in the public in the city of Fukushima during the days after radioactive fallout contamination.
zapperzero
#608
Jan18-13, 02:34 AM
P: 1,042
Apparently contractors hired for decon work in Fukushima prefecture are cutting (lots and lots of) corners, dumping radwaste into rivers and such.
http://ajw.asahi.com/article/0311dis...AJ201301170063
nikkkom
#609
Jan23-13, 05:06 AM
P: 595
Quote Quote by zapperzero View Post
Apparently contractors hired for decon work in Fukushima prefecture are cutting (lots and lots of) corners, dumping radwaste into rivers and such.
http://ajw.asahi.com/article/0311dis...AJ201301170063
"The photos show a man repeatedly kicking fallen leaves into a river in Tamura, Fukushima Prefecture, on Dec. 14."

Tamura is 40 kilometers West from Fukushima and lies in the area with Cs-137 levels below <300kBq/m^2.

If I would live there, I would _much_ prefer Cs-137 impregnated leaves to be gone to Pacific Ocean and diluted to zero than lingering around in some shallow dumps for decades to come. (Shallow because it is financially impractically costly to dig deep ones for all woody material existing in 40+ km radius around Fukushima.)

I recognize that public supervision in the form of press coverage is necessary to keep contractors honest.

But it often goes to the the idiotic levels of mass hysteria due to appalling lack of basic education, and lack of WILL to learn some data before getting hysteric and demanding impossible - that everything needs to be cleaned up 100% while not shipping any contamination anywhere.

Material contaminated by Cs-137 can not be destroyed. Isotopes do not burn, you know. It can be either buried, or diluted. Burial is a good solution, and it should be used for highly contaminated material, but it can't be used for everything. There should be a level of contamination below which the material is allowed to be disposed of in a cheaper way - yes, including dumping it into Pacific.
zapperzero
#610
Jan23-13, 06:44 AM
P: 1,042
Quote Quote by nikkkom View Post
There should be a level of contamination below which the material is allowed to be disposed of in a cheaper way - yes, including dumping it into Pacific.
As far as I know, dumping radwaste into oceans is a big no-no... Iirc the Russians had taken to putting waste in the North Sea? And there was a big stink about it? And then it was France? And again there was a big Stink?
nikkkom
#611
Jan24-13, 03:23 AM
P: 595
Quote Quote by zapperzero View Post
As far as I know, dumping radwaste into oceans is a big no-no...
Uh oh. "Radwaste". You know, my poop is a "radwaste" too, it has 50 Bq/kg of K-40.

Where do you prefer Japanese to put 10 million tons of very slightly radioactive wood and leaves?
Borek
#612
Jan24-13, 03:51 AM
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Several years ago Junior took a tourist trip to Chernobyl, and was told about results of different actions taken after the disaster.

Back in eighties during the cleaning up phase in some places they collected waste and covered it with the dirt/soil, and mounds are still radioactive. In other places it was not possible to collect the waste, so it was simply left and area was marked as no entry zone, and in the years that passed radioactive isotopes were flushed/diluted to the safe levels.

I am not trying to say dumping radwaste to oceans is a better solution, it is just that the final effect can be counterintuitive.


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