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Japan earthquake - contamination & consequences outside Fukushima NPP

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nikkkom
#487
Feb9-12, 07:48 PM
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Quote Quote by tsutsuji View Post
Elsewhere in Japan:
http://www.okinawatimes.co.jp/article/2012-01-31_29251/ 1.12 Bq/kg of cesium was found in eringi mushrooms grown in Nagano and eaten by schoolchildren in a south Okinawa Island school in November.
Is this right? Natural radiation (mostly from K-40) in human body is around 50 Bq/kg. Additional 1.12 Bq/kg in food is practically negligible - especially considering that it's Cs, which does not bioaccumulate in humans.
tsutsuji
#488
Feb10-12, 07:31 AM
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It is right, I think. The article says it is 0.46 Bq/kg of Cs-134 and 0.66 Bq/kg of Cs-137. I think that it is a problem that this article (like most articles about food) does not mention the presence of K-40 in bananas or other foods. People reading the article may unnecessarily worry too much.
tsutsuji
#489
Feb11-12, 05:47 AM
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Quote Quote by tsutsuji View Post
http://sankei.jp.msn.com/region/news...1550005-n1.htm 2077 Bq/kg dried shiitake mushrooms grown in Shizuoka were found in a shop in Yokohama. 7 bags (of 80 g each) have already been sold.
Grown mainly in Iwate and packaged in Shizuoka. Sorry.

http://www.nikkei.com/news/category/...AE2E2E2;av=ALL As a follow-up of the discovery in January of 43,780 Bq/kg high radiation ashes in a wood stove in Nihonmatsu, Fukushima prefecture, the ministry of environment checked wood stoves in 9 homes in 9 cities and towns in Southern Ibaraki prefecture . The lowest value was 1180 Bq/kg and the highest one 59,000 Bq/kg (resulting of the burning of 480 Bq/kg wood).

http://mainichi.jp/life/food/news/20...40016000c.html 258 Bq/kg in soba noodles in a restaurant in Okinawa. The noodles were manufactured using water percolating ashes from Fukushima wood. On 10 February, the Forestry Agency issued instructions so that wood from 17 prefectures produced after the 11 March earthquake are not used in food, even if they are below the radiation limits (40 Bq/kg for wood, 280 Bq/kg for charcoal).

http://mainichi.jp/select/weathernew...40046000c.html List of cities and towns in Fukushima prefecture where the 2011 rice harvest was found higher than 100 Bq/kg, with the numbers of such farms (170 farms in Fukushima city, 199 in Date, 111 in Nihonmatsu, 39 in Kunimi, 29 in Koori, 20 in Motomiya, 6 in Kawamata, 2 in Ootama and Soma, 1 in Tamura and Shirakawa) (Higher than 500 Bq/kg: 23 Farms in Fukushima city, 14 in Date, 1 in Nihonmatsu).
Astronuc
#490
Feb13-12, 07:19 AM
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A year [actually 11 months, but it seems it will go on] on, only brief home visits for Japan nuclear evacuees
http://news.yahoo.com/only-brief-hom...081517728.html
tsutsuji
#491
Feb18-12, 09:34 PM
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http://www.yomiuri.co.jp/dy/national/T120210006056.htm (English) Waste site open to journalists in Okuma

http://www.yomiuri.co.jp/feature/201...OYT1T00936.htm 58,000 Bq/kg from earth from discarded vinyl greenhouses from Togane, Chiba, being recycled in a plastic factory in Chiba prefecture. The factory has recalled all the earth (140 tons) produced after the nuclear accident.

http://www.yomiuri.co.jp/feature/201...OYT1T00881.htm A study group of the ministry of education and science held a meeting on 13 February about sea radiation surveys. They decided to launch another survey of river mouths and seas in Tokyo Bay and on the Pacific coast, with Fukushima prefecture as the main focus, starting in April. The frequency of testing in coastal waters and in far waters will be reduced to once every 2 or 3 months instead of once a month.

http://www.yomiuri.co.jp/feature/201...OYT1T00538.htm 3000 Bq/kg in dried daikon radish grown in Fukushima city. 102 bags (50 g each) have already been sold.

http://www.okinawatimes.co.jp/article/2012-02-08_29578/ 468 Bq/kg in Fukushima wood in an Okinawa restaurant. 3 Other restaurants have already used their Fukushima wood so it cannot be tested, but 39,960 Bq/kg was found in ashes. 15.7 tons of Fukushima wood were distributed in Okinawa by a Gifu prefecture based company. 8.4 tons were sold to restaurants, and 7.3 tons are remaining in a container near Naha port.

http://www.chibanippo.co.jp/c/news/national/69198 Chiba prefecture tested 46 locations in a park and found 3 locations above the 1 microsievert/hour standard. The highest is 3.42 microsievert/hour at 50 cm above ground near a parking lot storm-water inlet.

http://www.tokyo-np.co.jp/article/na...402000037.html 6.85 microsievert/hour at 1 cm above ground (above the 0.59 microsievert/hour at 1 cm above ground standard) near an unused drainage channel near a school in Yokohama. 62,900 Bq/kg in earth samples taken in a close location.

http://www.minyu-net.com/news/news/0204/news6.html Second announcement of results of the whole body counter examinations of Minamisoma citizens. The first results were announced in October. Among 579 primary and middle school children, 218 were above the detection level for Cs-137 and 361 were below detection level. 4 had 20 Bq/kg or above. The highest one had between 30 and 35 Bq/kg. Among 4745 senior high school students, 1943 were above detection level. Among these, 1774 had 20 Bq/kg or below. 16 had 50 Bq/kg or above. The highest had 110.7 Bq/kg. According to the City, only one person had an accumulated dose higher than 1 milisievert over 50 years, with 1.069 milisievert/50 years.

http://mainichi.jp/select/weathernew...40102000c.html There is a problem with the new food safety levels. There are two sorts of radiation measurement tools. The Germanium semiconductor detector, and the sodium iodide scintillator detector. As a rule, one should have a detection level of about 10% of the safety standard. As the safety standard for general food is brought down to 100 Bq/kg, one should have a detection level of 10 Bq/kg. This is possible with a Germanium (Ge) detector, but sodium iodide (NaI) detectors can't do this. At present the national government and the prefectures own 116 Ge detectors and 227 NaI detectors. The person in charge at Ibaraki prefecture government says "we don't have the budget to buy new detectors. We have to do with the detectors we have". Ibaraki prefecture owns one Ge detector, which performs between 15 and 20 tap water tests per week, and 5 NaI detectors, that perform beef tests on 500 to 600 cows per week. When the 100% beef control was started in August, they had only one Ge detector, and for two months they had to perform tests on a 24 hour/day basis, and the employees could hardly sleep. They are afraid that the same situation is going to occur again as the new safety levels are implemented. The health ministry issued a proposal to set the NaI detector detection level at 25 Bq/kg, but according to the maker, Hitachi Aloka Medical, the test must last for 60 to 70 minutes instead of the present 10 to 15 minutes. To reduce that time, and increase the measurement tool's sensitivity, the sample holding container would need to be improved. Miyagi prefecture has decided to perform such improvements, but it will cost 13 million yens. "Can the national government help with the improvement cost?" the Miyagi prefecture person in charge is asking.
Neredera
#492
Feb19-12, 10:21 AM
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Quote Quote by Astronuc View Post
A year [actually 11 months, but it seems it will go on] on, only brief home visits for Japan nuclear evacuees
http://news.yahoo.com/only-brief-hom...081517728.html
This article links a picture that shows a 11.3mSv/h reading.

http://news.yahoo.com/photos/world-e...081517930.html

That has to be a mistake and should be 11.3 uSv/h, or not?
tsutsuji
#493
Feb19-12, 11:20 AM
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Quote Quote by Neredera View Post
This article links a picture that shows a 11.3mSv/h reading.

http://news.yahoo.com/photos/world-e...081517930.html

That has to be a mistake and should be 11.3 uSv/h, or not?
Yes it should be 11.3 μSv, as you can see on the larger version of the photograph at http://www.novosti.rs/upload/images/...2/13/japan.jpg
zapperzero
#494
Feb21-12, 01:52 AM
P: 1,044
http://www3.nhk.or.jp/daily/english/20120220_26.html

partial results of an ongoing survey in Fukushima:

40% of residents from 3 affected municipalities got more than 1 mSv in the first four months after the accident.

Highest dose received was 23 mSv.
tsutsuji
#495
Feb21-12, 05:22 PM
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http://www3.nhk.or.jp/news/genpatsu-...5_sokutei.html The ministry of education and science is releasing a new online map with real time radiation measurements in 2700 places such as schools and parks in Fukushima prefecture. A trend graph is provided for each sensor.

http://radioactivity.mext.go.jp/ja/i...2012022114.pdf presentation of the new real time map.

http://radiomap.mext.go.jp/ja/ The new real time map.

[It is a bit disappointing that they don't say the height of each sensor. All they say is "either 50 cm or 1 m". Another problem is the 3 microsievert/hour upper limit of the trend graph. With about 9 microsievert/hour, the trend graph of Namie's prefectural high school is not available as it is higher than 3 microsievert/hour]
Astronuc
#496
Feb23-12, 07:24 PM
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The Health Physics Society (HPS) is concerned about radiation exposures associated with these reactor problems and desires to keep our members and the concerned public advised on current events associated with the Japanese nuclear plants.
http://hps.org/fukushima/

The Health Physics Society has a lot of relevant information on the health and environmental effects of radiation.
tsutsuji
#497
Feb25-12, 06:48 AM
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Quote Quote by zapperzero View Post
http://www3.nhk.or.jp/daily/english/20120220_26.html

partial results of an ongoing survey in Fukushima:

40% of residents from 3 affected municipalities got more than 1 mSv in the first four months after the accident.

Highest dose received was 23 mSv.
http://www3.nhk.or.jp/news/genpatsu-...ibakuryou.html Results of the external radiation estimates for 14,680 people of Iitate, Namie and Kawamata, for the 4 month period after the accident. Among the 9747 people who are not nuclear workers, 4111 are above 1 mSv, 71 are above 10 mSv. The highest is a woman with 23 mSv. She evacuated once, but came back and lived for 3 months in the planned evacuation zone.

Quote Quote by tsutsuji View Post

http://radioactivity.mext.go.jp/ja/i...2012022114.pdf presentation of the new real time map.

http://radiomap.mext.go.jp/ja/ The new real time map.

[It is a bit disappointing that they don't say the height of each sensor. All they say is "either 50 cm or 1 m".
http://ajw.asahi.com/article/0311dis...AJ201202220028 "It measures air radiation levels of gamma rays at a height of 50 centimeters above the ground in kindergartens, day care centers and elementary schools and at a height of 1 meter above the ground at junior high and senior high schools and at other public facilities."

http://www.bbc.co.uk/news/science-environment-17124909 "research cruise in June last year led by the Woods Hole Oceanographic Institution (WHOI).The initial findings were presented to the biennial Ocean Sciences Meeting. "

http://www3.nhk.or.jp/news/genpatsu-...1430_100m.html The ministry of environment is releasing an interim report with a 100 metre mesh radiation map. It was started in November and displays the measurements in 7963 locations. Some of the areas in the central part of Iitate village that were marked as above 20 mSv/year in the helicopter maps were found below 20 mSv/year. The highest location is in the Yamada district of Futaba with 89.9 microsievert/hour (472.5 milisievert/year). The final report will be released next month. It will be used by local governments to plan decontamination, and by the national government to revise the boundaries of the evacuation zones.

http://www.env.go.jp/press/press.php?serial=14870 Detailed monitoring pursuant of decontamination special law (interim report)
zapperzero
#498
Mar2-12, 01:20 AM
P: 1,044
Xenon-133 and caesium-137 releases into the atmosphere from the
Fukushima Dai-ichi nuclear power plant: determination of the
source term, atmospheric dispersion, and deposition

http://www.atmos-chem-phys.net/12/23...-2313-2012.pdf

Regarding 137Cs, the inversion results indicate a total
emission of 36.6 (20.1–53.1) PBq, or about 43% of the estimated
Chernobyl emission. This means that nearly 2% of
the available inventory of the reactor cores in units 1–3 and
the spent-fuel pool in unit 4 was discharged into the atmosphere.
The inversion strongly increased the emissions early
on 12 March, around the time when the first explosion occurred
in unit 1. These early emissions were estimated lower
by the Japanese authorities, but are in accordance with the
first estimates published by Central Institute for Meteorology
and Geodynamics (2011). The highest release rates occurred
on 14 March, when hydrogen explosions occurred in reactor
units 3 and 4 and, presumably, unit 2. We also find unexpectedly
high 137Cs emissions from 16–19 March, which
suddenly dropped by orders of magnitude when spraying of
water on the spent-fuel pool of unit 4 started. Thus, we believe
that these high emissions are related to the degraded
fuel in the spent-fuel pool of unit 4, and this result would
also confirm that the spraying was an effective countermeasure
at least in this case.
Exactly
during and following the period of the highest 137Cs emission
rates on 14 and 15 March, the FD-NPP plume was advected
towards Japan and affected large areas in the east of
Honshu Island. The advection towards Japan was triggered
by a developing cyclone, which produced precipitation on 15
March, leading to the deposition of large fractions of the airborne
137Cs over Japanese land. However, the situation could
have been even much worse, as fortunately no rain occurred
at the time
During a second episode from 20–22 March, even larger
areas of Honshu were covered by the FD-NPP radioactive
cloud, from Shizuoka prefecture in the south to areas
north of FD-NPP. Strong frontal precipitation nearly completely
cleansed the atmosphere of 137Cs and again produced
strong deposition of this radionuclide over Honshu, including
Tokyo. This episode again followed a period of high (though
fortunately not as high as on 14–15 March) 137Cs emission
fluxes on 19 March, which were transported to Japan on 20
March.
tsutsuji
#499
Mar2-12, 03:11 PM
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http://sciences.blogs.liberation.fr/...enne-irsn.html The French IRSN will publish a report on the Fukushima accident on the first anniversary of the accident [that must be on 11 March 2012].


Releases into the air:

radioactive noble gasses : 6550 PBq (petabecquerels =10^15 Bq) (≈ Chernobyl), mostly xenon 133 (133Xe, period of 5,3 years)

Radioactive iodines : 408 PBq (about one tenth of Chernobyl), including 197 PBq of iodine 131 (131I, period of 8 days) and 168 PBq of iodine 132 (132I, period de 2,3 hours)

Radioactive telluriums : 145 PBq including 108 PBq of tellurium 132 (132Te, period of 3,2 days) and 12 PBq of tellurium 129m (129mTe, period of 33,6 days)

Radioactive cesiums : 58 PBq (about three times less than Chernobyl), including 21 PBq of cesium 137 (137Cs, period of 30 years), 28 PBq of cesium 134 (134Cs, period of 2,1 years) and 9,8 PBq of cesium 136 (136Cs, period of 13,2 days)

http://sciences.blogs.liberation.fr/...-28fev2012.pdf IRSN press release of 28 February 2012, page 3
nikkkom
#500
Mar3-12, 06:09 AM
P: 611
Quote Quote by tsutsuji View Post
http://sciences.blogs.liberation.fr/...enne-irsn.html The French IRSN will publish a report on the Fukushima accident on the first anniversary of the accident [that must be on 11 March 2012].
"radioactive noble gasses : 6550 PBq (petabecquerels =10^15 Bq) (≈ Chernobyl), mostly xenon 133 (133Xe, period of 5,3 years)"

Xe-133 period is 5.2 days, not years.
tsutsuji
#501
Mar5-12, 11:23 AM
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Xe-133 period is 5.2 days, not years.
oops. sorry for the mistake.

Quote Quote by tsutsuji View Post
http://www3.nhk.or.jp/news/genpatsu-...124/index.html As a countermeasure decided after finding that contaminated stones were delivered from a contaminated stone pit in Namie, the government is goint to check construction materials from the restricted zone. The namie stones were used in the concrete which was used to build a new appartment building in Nihonmatsu and high radiation levels were measured inside the appartments. A report will be issued within this month. Concerning the preparation of national safety level for construction materials, the nuclear disaster response headquarters said "it will take time to study it".
http://www3.nhk.or.jp/news/genpatsu-...228/index.html A ministry of Economy and Industry study group is proposing a 100 Bq/kg safety limit for crushed stones.

http://www3.nhk.or.jp/news/genpatsu-...40_ochiba.html The Forestry agency made a study of fallen leaves in 400 locations in Fukushima Prefecture. In a location 10 km west of the plant and in a location 25 km north-west of the plant the radiations were both 4,440,000 Bq/kg.

http://www3.nhk.or.jp/news/genpatsu-...305/index.html An NHK survey found that there is a strong suspicion that at least 5 people left isolated in the evacuated zone died of starvation. The body of a man in his seventies was found at the end of March on the second floor of a house located 5 km away from the plant. The first floor had been damaged by the tsunami. A woman in her sixties was found dead in her house in April. She had a chronic disease affecting her legs. Her house did not suffer large tsunami damage. All five bodies were thin as a consequence of losing weight. The police and the doctors who examined the bodies say that there is a high probability that they weren't able to evacuate by themselves or to call for help. The NHK found that the detailed causes of the bodies found on tsunami sites were not researched using autopsies and were counted as "drowned". The doctors say that it is possible that among the people counted as "drowned", some of them might have survived for some time and died later from a different cause. Several evacuation zone firemen testify that before the rescue operations were halted, they had heard voices of survivors trapped in the tsunami debris, calling for help. Yoshihisa Takano, a Namie fireman, recalls that after hearing voices and rattling in the debris, he went back to the town hall to call for help, but there weren't people or equipment available, and another tsunami warning came. Finally it was decided to resume rescue operations the next morning. But the next morning, the evacuated zone was extended to the 10 km range, and evacuating the 10 km range became the priority. "I am still regretting today that we did not go to rescue this/those person(s), although I had told him/them "we will come tomorrow for for help, please wait"".

http://www3.nhk.or.jp/news/genpatsu-...850_gashi.html According to an NHK survey, the number of patients from evacuated hospitals who died during the long hours of evacuation or after their health deteriorated shortly after evacuation is at least 68. Asked about the 5 people strongly suspected of having died of starvation, isolated at home or near their homes, the NISA said it is studying a revision of the guidelines so that cities and villages have to specify in their evacuation plans the method by which they will respond to the citizens who need help to evacuate, and the method by which they check that no citizen is left behind.
tsutsuji
#502
Mar6-12, 01:51 PM
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http://www.yomiuri.co.jp/feature/201...OYT1T01065.htm According to the Japan Agency for Marine-Earth Science and Technology, the quantity of Cesium that flowed into the ocean is 6 times as much as the Tepco estimate. It was announced at a research reporting conference at JAEA on 6 March. This research is based on seawater samples in 500 locations and a simulation of cesium migration until 7 May 2011. The contaminated water that flowed into the ocean was estimated between 4200 and 5600 TBq of cesium. The cesium released into the atmophere that sunk into the ocean (with the rain, etc.) is estimated between 1200 and 1500 TBq.
etudiant
#503
Mar6-12, 02:06 PM
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Quote Quote by tsutsuji View Post
http://www.yomiuri.co.jp/feature/201...OYT1T01065.htm According to the Japan Agency for Marine-Earth Science and Technology, the quantity of Cesium that flowed into the ocean is 6 times as much as the Tepco estimate. It was announced at a research reporting conference at JAEA on 6 March. This research is based on seawater samples in 500 locations and a simulation of cesium migration until 7 May 2011. The contaminated water that flowed into the ocean was estimated between 4200 and 5600 TBq of cesium. The cesium released into the atmophere that sunk into the ocean (with the rain, etc.) is estimated between 1200 and 1500 TBq.
These estimates don't square with the IRSN estimates of about 58,000 Terabequerels of cesium. We are out by almost a factor of 10.
Also, the IRSN mentions very large early releases of tellurium, which presumably decay to iodine in short order. These were not mentioned afaik in the various TEPCO releases. Were they summarized with the iodine levels?
clancy688
#504
Mar6-12, 02:46 PM
P: 546
Quote Quote by etudiant View Post
These estimates don't square with the IRSN estimates of about 58,000 Terabequerels of cesium. We are out by almost a factor of 10.
I think they do. You compare the wrong levels.

First of all, IRSN claimed that 58 PBq of Cesium were released via the atmosphere, not water. Moreover, those 58 PBq are all kinds of Cesium - 137 (21 PBq), 136 (9.8 PBq) and 134 (28 PBq).

But there's another estimate for release into the ocean. They claim that 27 PBq of Cesium-137 was released into the sea.
TEPCOs initial estimate was 4.2 to 5.6 PBq C-137 released. Six times that estimate would be 25.2 to 33.6 PBq. Which puts it right into the vicinity of the IRSN estimate.


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