Japan earthquake - contamination & consequences outside Fukushima NPP

[joewein]

Not necessarily. Lots of radioactive steam may have been produced.

If the SFP of unit 4 was the source for the radioactivity in Ibaraki one would expect significant fuel rod damage in the pool.

However that is at odds with the https://www.physicsforums.com/showpost.php?p=3373625&postcount=10224" of the pool water in unit 4, which is about 100 times lower than in unit 1, 700 times lower than in unit 2 and 1000 times lower than in unit 3.

 

[Astronuc]

I've haven't fully explored this, but

Fukushima radiation map published
http://www.neimagazine.com/story.asp?storyCode=2060679
19 September 2011

The Japanese government (MEXT) has issued a contour map of cumulative radioactive dose in air in the 50 km or so of northeastern Japan around the Fukushima Daiichi site, to 11 September.

. . . .

 

[joewein]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20110920/0440_keikai.html In his address to the IAEA general conference in Vienna on 19 September, Goshi Hosono said that the completion of step 2 (cold shutdown) does not necessarily mean that the restricted zones will be changed or shrunk. Reducing radiations to such levels that do not affect health will take time and an effective method of disposal of the waste generated by the decontamination work has not been found yet.

Let's send a letter of thanks to Capitain Obvious here.

While it may be obvious to you and me, it is not obvious to the general public here in Japan, or at least not the way things were presented here by the media.

The public here was basically sold on the idea that the evacuation was temporary and would last until "cold shutdown" has been achieved, which was promised by the turn of the year. That is because originally evacuation was justified as a precaution after the cooling problems, not as response to acute contamination of the environment, which was never supposed to happen since the containments would prevent Chernobyl-style contamination.

Since then the truth about soil contamination, both inside the 20 km exclusion zone and in the strip of land to the NW of the plant (Iitate-mura, etc) and even further away has gradually trickled out, but it didn't drastically change the official storyline. Nobody was saying, "No, you won't be able to return in January, even if the reactors are below 100 deg C."

The whole idea of cold shutdown becomes questionable without circulation cooling. Once the RPV and its pipes, seals and valves are penetrated by melted fuel or lose air tightness, as they have, it is no longer possible to circulate water through the RPV and a heat exchanger (like the Residual heat Removal system) as in a normal cold shutdown.

The water will leak out somewhere. If the fuel can't be submerged, steam can form locally. If the seals are no longer tight the steam can leak out. In a way, the covers around the buildings and any filtration applied to them are more significant now than the stretched definition of "cold shutdown" applied to the reactor core.

There has been little discussion about what kind of decontamination is possible or feasible in the evacuated areas, except that TEPCO has said that it would decontaminate them so residents can return, and for months locals have been shown in interviews on TV saying they want to return "as soon as possible" (literally, "if I can return one day sooner, I want to").

 

[zapperzero]

While it may be obvious to you and me, it is not obvious to the general public here in Japan, or at least not the way things were presented here by the media.

The public here was basically sold on the idea that the evacuation was temporary and would last until "cold shutdown" has been achieved, which was promised by the turn of the year. That is because originally evacuation was justified as a precaution after the cooling problems, not as response to acute contamination of the environment, which was never supposed to happen since the containments would prevent Chernobyl-style contamination.

Man oh man. What a pickle. Do you suppose the current gov't will be short-lived as well?

 

[alpi]

Nobody was saying, "No, you won't be able to return in January, even if the reactors are below 100 deg C." ...

Why would any responsible politician say such a thing? I think people should be allowed to return to their homes immediately. The radiation doses indoors where modern people spend most of their lives are less than the reported fairly harmless doses outdoors in the affected areas.

 

[rowmag]

According to a post made today at the ex-skf blog, we were not the only people to notice that spike - the blog has translated an article from Playboy which postulates a fresh release of radioactive isotopes around the time:

http://ex-skf.blogspot.com/2011/09/japanese-researcher-recriticality-in.html

A couple of personal observations. Firstly, I have been watching these graphs since March 15th, and that radioactive rainstorm is unique as far as I am concerned - I do not think the 'radon daughter theory' explains it adequately. Wouldn't we be able to see this pattern repeated if the radiation was attributable to natural causes? Also, the peak occurred over a a large geographic area.

Secondly, should we take an article in 'Playboy' seriously? The story cites Yoyo Hinuma, currently at University of California San Diego, so it is not just a 'baseless rumour'. I think the theory should at least be considered on its scientific merits. I'm not a scientist, however I do know a bit about the structure of the media establishment in Japan.

Self-censorship in the Japanese media is a well understood phenomenon amongst Japanese media scholars, and almost all big stories are broken through the 'weekly' tabloids. The Neptunium contamination story is a good example - based on solid University of Tokyo research but only reported by 'SPA!'.

So, all that said, why DID the radiation stop after the rain storm on August 19th? And why was there no iodine or cesium detected in the daily municipal fallout figures, yet iodine suddenly reappears in the sewage sludge in Tokyo, Iwate, Niigata, Nagano and the Sub-drain at Fukushima Unit 1? If we consider Dr Hinuma's theory about re-criticality, could other short-lived fission products explain the radioactive rain we experienced on the 19th of August?

http://i55.tinypic.com/2lavqee.jpg

Another blip seen in Ibaraki on Sep. 21st, when the center of Typhoon #15 was passing to the west through Tochigi: strong rain, combined with wind blowing from Fukushima Daiichi (clockwise around the center of the storm). And once again the level dropped again after the storm had passed.

Of course, the typhoon brought very intense rains, so the wind direction could be a coincidence if the theory of radon daughters being kicked up from the soil by rain is correct. But, I think if the radon daughter theory is to be demonstrated, we need to see such a blip when the wind is NOT coming from the direction of Fukushima Daiichi.

Otherwise, what could be getting swept downwind from Fukushima Daichi, and then swept down with the rain, that is either short-lived or doesn't stick around? Noble gases?

 

[tsutsuji]

http://www3.nhk.or.jp/news/html/20110924/t10015820321000.html 500 Bq/kg of cesium found in rice tested before harvest in Nihonmatsu, Fukushima prefecture.

 

[Luca Bevil]

Why would any responsible politician say such a thing? I think people should be allowed to return to their homes immediately. The radiation doses indoors where modern people spend most of their lives are less than the reported fairly harmless doses outdoors in the affected areas.

Should not be this forum about scientific facts ?

Do you propose to keep children confined in radiation shielded buildings ?

I habe sove difficulty in wording my strong disagreement in a civil manner, so I'll leave it at this point and let others comment

 

[Azby]

Why would any responsible politician say such a thing? I think people should be allowed to return to their homes immediately. The radiation doses indoors where modern people spend most of their lives are less than the reported fairly harmless doses outdoors in the affected areas.

I wonder if we're talking about the same geographic locations. Unless my translation is hazy (and they often are) the statement refers to the most highly contaminated areas within the 20km exclusion zone as well as less contaminated ones. Maybe you were thinking it was only the latter? Like the rest if us I'm wondering who was thinking they'd be able to go back and live in an area where the ground contamination is over 3,000,000 Bq/m2, but apparently the gov't has really avoided coming out and saying this until now, and many people were holding out hope.

 

[Caniche]

I wonder if we're talking about the same geographic locations. Unless my translation is hazy (and they often are) the statement refers to the most highly contaminated areas within the 20km exclusion zone as well as less contaminated ones. Maybe you were thinking it was only the latter? Like the rest if us I'm wondering who was thinking they'd be able to go back and live in an area where the ground contamination is over 3,000,000 Bq/m2, but apparently the gov't has really avoided coming out and saying this until now, and many people were holding out hope.

Well they say it springs eternal, but you might ask if 56,000 years is pushing it a bit

 

[tsutsuji]

The evacuation-prepared zone will be lifted Friday:

The five municipalities have already submitted to the government their recovery plans, a precondition for lifting the advisory which covers all of Hirono and parts of Naraha, Kawauchi, Tamura and Minamisoma, all in Fukushima Prefecture.
http://www.tmcnet.com/usubmit/2011/09/27/5807576.htm

Japan Focus is publishing "Fukushima Children at Risk of Heart Disease" by Chris Busby with an introduction by Mark Selden : http://japanfocus.org/-Mark-Selden/3609 . I tried to find basic knowledge on the "Chernobyl heart" disease, and found http://en.wikipedia.org/wiki/Chernobyl_Heart . It is mostly an article about a film, but it links to a medical publication : "Radiation induced cardiac valve disease in a man from Chernobyl" : http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=search&db=pubmed&term=19647162

 

[Shinjukusam]

The evacuation-prepared zone will be lifted Friday:


Japan Focus is publishing "Fukushima Children at Risk of Heart Disease" by Chris Busby with an introduction by Mark Selden : http://japanfocus.org/-Mark-Selden/3609 . I tried to find basic knowledge on the "Chernobyl heart" disease, and found http://en.wikipedia.org/wiki/Chernobyl_Heart . It is mostly an article about a film, but it links to a medical publication : "Radiation induced cardiac valve disease in a man from Chernobyl" : http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=search&db=pubmed&term=19647162

Just wanted to point out that pretty much anything having to do with Busby should be taken with a pretty large grain of salt

Feel I need to be pointing out the other side of the "it's not science, it's propaganda" discussion.

 

[tsutsuji]

I want to correct one of my previous messages as below with the underlined text:

http://www3.nhk.or.jp/news/genpatsu-fukushima/20110922/1440_youso.html The ministry of education and science releases a map of Iodine pollution. Iodine 131 has an 8 day long half life. Of the 2200 measurement points, only 400 provided relevant data. There is a polluted area with the same shape as the Cs-137 pollution area, but there is also an area with relatively high iodine levels in the south of the plant. The Iodine 131/Cesium 137 ratio is higher in the North-West area than in the South area.

http://radioactivity.mext.go.jp/ja/distribution_map_around_FukushimaNPP/0002/5600_0921.pdf 　The Iodine map is on page 6 with concentrations as of 14 June. It shows yellow dots in the 20-30 km stay-indoors zone south of the plant (mostly Hirono).

Rice contamination:

http://www3.nhk.or.jp/news/html/20110924/t10015820321000.html 500 Bq/kg of cesium found in rice tested before harvest in Nihonmatsu, Fukushima prefecture.

Consequences:

Rice with 500 becquerels of cesium per kilogram still can be shipped. Fukushima Prefecture will conduct the official tests of rice for radiation in Nihonmatsu as soon as possible at 300 spots—many more than the initially planned 38 spots
http://online.wsj.com/article/SB10001424053111903791504576590724000963708.html

Scientific problem:

The level of radioactive materials in soil at the paddy field where the rice was harvested was 3,000 becquerels per kilogram.

"The cesium level [at 500 becquerels per kilogram] of the rice was higher than it was supposed to be, given the radionuclide transfer coefficient. I wonder why such a high level of cesium was detected from this place alone," an official of the prefectural government said.
http://www.yomiuri.co.jp/dy/national/T110924003191.htm

http://www3.nhk.or.jp/news/html/20110929/k10015937093000.html Personnel in 3 fishing cooperatives in Soma and Iwaki, Fukushima prefecture, are being trained to use 5 new radiation monitoring instruments able to provide data as soon as the fish is landed. Being able to provide data quickly is important as fish is consumed shortly after being caught. The new tools will be used with trial catches in November at the earliest.

http://new-fukushima.jp/result.php?search_area=いわき市 Three fish species were above the limits in Iwaki : fat greenling (930 Bq/kg of Cs 137), commons skete (520 Bq/kg of Cs 137), slime flounder (620 Bq/kg of Cs 137), all three were caught on 26 September. Another common skete sample had only 160 Bq/kg of Cs 137.

http://new-fukushima.jp/result.php?search_area=相馬市 Samples of some of those species caught on the same day in Soma were below the limit (fat greenling: 90Bq/kg, common skete: 40 Bq/kg for one sample and 100 Bq/kg for another)

http://www.tokyo-np.co.jp/article/ibaraki/20110916/CK2011091602000060.html The fishing of odontobutis obscura (donko) is allowed again in Ibaraki prefecture from 15 September. It had been found above allowed radiation levels and fishing had been stopped in July and August, but recently taken samples are below the limits. Bottom trawling is still avoided north of Kawajiri (Hitachi city), and this is a huge loss as it is a major shrimp fishing area.

Other foods, such as marine produce, won't be as easy to handle, experts say. After the Chernobyl accident, for example, the radioactive contamination of fish peaked between 6 to 12 months after the disaster.
http://search.japantimes.co.jp/cgi-bin/nn20110911a3.html

http://new-fukushima.jp/result.php?search_area=南相馬市&kind_detail=&page=2 　Lactarius (hatsutake) mushrooms found with 11,000 Bq/kg on samples taken on 15 September in Minamisoma.

 

[tsutsuji]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20110930/2040_kensyutsu.html Plutonium has been found in Iitate Mura, 45 km away from the plant, with 0.82 Bq/m² of Pu-238. Adding Pu-239 and Pu-240, the total is 2.5 Bq/m². This is one of the results of a survey performed by the ministry of education and science at 100 locations inside the 80 km range in June and July. It is the first time a government survey finds plutonium outside the plant.

http://www.nikkei.com/news/headline...19695E1E2E2E6868DE1E2E2EBE0E2E3E3E2E2E2E2E2E2 Plutonium was found at 6 locations. The highest figure is 4 Bq/m² at Namie.

http://radioactivity.mext.go.jp/ja/distribution_map_around_FukushimaNPP/0002/5600_0930.pdf "Ministry of education and science plutonium and strontium substance analysis results" 30 September 2011

 

[joewein]

http://www.nikkei.com/news/headline...19695E1E2E2E6868DE1E2E2EBE0E2E3E3E2E2E2E2E2E2 Plutonium was found at 6 locations. The highest figure is 4 Bq/m² at Namie.

I wonder what the general background level from Pu from the 1950s/1960s above ground tests is?

From 1955-1966 plutonium deposition (Pu239+Pu240) in Japan from weapon testing by the nuclear powers was above 1 Bq/m2 annually, with a cumulative total of about 40 Bq/m2 during those years alone. Given the long half lives (24110 for Pu239 and 6537 for Pu240), most of that should still be around.

 

[tsutsuji]

I wonder what the general background level from Pu from the 1950s/1960s above ground tests is?

From 1955-1966 plutonium deposition (Pu239+Pu240) in Japan from weapon testing by the nuclear powers was above 1 Bq/m2 annually, with a cumulative total of about 40 Bq/m2 during those years alone. Given the long half lives (24110 for Pu239 and 6537 for Pu240), most of that should still be around.

That problem is adressed at paragraph 4.2 of http://radioactivity.mext.go.jp/ja/distribution_map_around_FukushimaNPP/0002/5600_0930.pdf : the Pu238/(Pu239+Pu240) ratio found in Japan in 1999-2008 is, as shown in Attachment 3 (the last one at the bottom of the pdf) 0.026. The present measurements reveal ratios between 0.33 and 2.2 for five samples. For that reason it is thought that the deposits are new deposits created by the plant. Also in one location only Pu238 is found and Pu239+Pu240 is below detection level. The ratio for that sample, using the detection level for Pu-239-240 (0.5 Bq/m²) is also significantly higher than the 1999-2008 ratio. [I think the shape of the Pu238 map, being similar with the shape of the Cesium map is also significant]

It turns out that when the Nikkei says "6 locations" it means "6 locations with a significantly high Pu238/(Pu239+Pu240) ratio. The map shows a lot of locations with a grey triangle, which means that only Pu239+Pu240 was found while Pu238 was not found.

erratum (adding the underlined text):

http://www.nikkei.com/news/headline...19695E1E2E2E6868DE1E2E2EBE0E2E3E3E2E2E2E2E2E2 The highest figure for Pu238 is 4 Bq/m² at Namie.

 

[M. Bachmeier]

Feel I need to be pointing out the other side of the "it's not science, it's propaganda" discussion.

Try not to be too hard on a man who has been trying to fight against financial influence corrupting scientific surety. He is notable for many truths and many absences of truth discovered. His failings have likely to do more with his age and fear than an honest account of observation.

 

[tsutsuji]

Beef:

In some cases, slaughterhouses in other prefectures are refusing to accept Fukushima cattle because of concerns that the screening process isn't stringent enough.

To dispel those concerns, the Fukushima Prefectural Government is trying to determine how amounts of radioactive matter in blood and meat are related.
http://search.japantimes.co.jp/cgi-bin/nn20111002x3.html

 

[Shinjukusam]

Try not to be too hard on a man who has been trying to fight against financial influence corrupting scientific surety. He is notable for many truths and many absences of truth discovered. His failings have likely to do more with his age and fear than an honest account of observation.

Fear should not be an excuse, this is a matter of science. I don't care if he's scared of what could happen, I want to know what is happening.

 

[Astronuc]

For those interested:

International Symposium on Decontamination:
Towards the Recovery of the Environment

The Cabinet Office, Government of Japan, will hold an International Symposium on Decontamination under the co-sponsorship of the Ministry of the Environment. The objective of the symposium is to share experience and best practices in the remediation of land contaminated with radioactive materials, and to contribute to the planning and effective management of decontamination activities in Japan.

Date: 16 October 2011
Time: 10:00 - 18:30 (registration from 9:00-)
Venue: Convention Hall "Paluse Iizaka"
Iizakamachi, Fukushima-city, Fukushima-prefecture, 960-0201 Japan


http://www.oecd-nea.org/press/2011/NEWS-07.html

The symposium is open for the public, and registration must be made by Oct 7.

 

[tsutsuji]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111005/0730_suiden.html Theories are proposed to explain the 500 Bq/kg rice in Nihonmatsu : the presence of much sand in the soil, which might enhance cesium absorption by the rice, or the presence of 10,000 Bq/kg and higher soil higher in the mountains, with rainwater bringing the radioactive substances down to the rice fields. Further surveys will be performed in the surrounding mountains.

 

[Astronuc]

Clean-up in Fukushima
05 October 2011
http://www.world-nuclear-news.org/RS_Clean_up_in_Fukushima_0510111.html

Most of these were from the 20 kilometre radius of compulsory evacuation, while more people left the next 10 kilometre band where official instructions were to prepare for evacuation should the accident worsen. About another 20,000 in a separate sector extending about 50 kilometres to the northwest were recommended to evacuate because radioactivity deposited there was leading to dose rates of over 20 millisieverts per year.

This compares to a global average background dose rate of 2.4 millisieverts per year from natural sources to which all people are exposed with no apparent ill effects. . . . .

Children who have been exposed will have to be monitored for two or more decades.

 

[Caniche]

Clean-up in Fukushima
05 October 2011
http://www.world-nuclear-news.org/RS_Clean_up_in_Fukushima_0510111.html



Children who have been exposed will have to be monitored for two or more decades.

"representing the people and organisations of the global nuclear profession" I guess that mission statement is at least an honest declaration of bias.

As a point of interest ,does anyone know ,if, and if so ,how ,these 'experts' distinguish between "natural" background radiation and background radiation resulting from previous accidents/incidents and bombs and bomb tests.

You have to applaud the stated ambition of the clean up campaign to reduce the levels of radioactive pollution to "half" the 'natural' background level.

 

[tsutsuji]

http://mainichi.jp/select/weathernews/news/20111006dde012040008000c.html There are limits to how much you can decontaminate with pressure washers. Pr. Yamauchi of Kobe university tells about his findings at a building used for children after-school care in Fukushima city. Inside the building, the floor had 0.33 μSv/h, the beams had 0.52, and just below the roof, it was 0.72 μSv/h, and he understood that the radiation increased with the height. So he checked the roof, outside, and it was 1.79 μSv/h. The roof had been cleaned using a pressure washer, but the radiation could not be reduced more. He is afraid the roof must be changed. He says the goal is to create secure areas where the radiation inside buildings is as low as 0.05 μSv/h as it was before the accident. Pr Kodama of Tokyo university says that in a kindergarten in Minamisoma there were mini hot spots such as the roof (33 μSv/h) and below the toboggan (5~10 μSv/h). After cleaning it once, the roof's radiation was lowered by 50%. It will be difficult to bring it to the 0.5 μSv/h goal, he says. Probably the surface must be removed or the whole roof must be changed. Know-how from house construction companies is needed.

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_111001_02-e.pdf Dealing with higher levels of radiation inside the plant, using dust collectors, Tepco achieves decontamination rates of about 30%, bringing the radiation from 0.48 to 0.33 mSv/h on asphalt.

 

[tsutsuji]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111007/0520_hibaku.html Until now nuclear worker safety regulations were limited to the jobs indoors or inside nuclear plant premises. So the ministry of labour and health has created a new regulation for the workers who perform decontamination tasks outside the plant, requiring to wear masks, to wear radiation measuring instruments, etc. Some citizen groups had complained that some outdoor workers were not sufficiently protected from radiations.

http://radioactivity.mext.go.jp/ja/1910/2011/09/1910_092917_1.pdf Saitama and Chiba helicopter survey results

http://radioactivity.mext.go.jp/ja/1910/2011/10/1910_100601.pdf Tokyo and Kanagawa helicopter survey results

http://radioactivity.mext.go.jp/ja/5000/2011/10/5000_100601.pdf Aomori helicopter survey plan

http://radioactivity.mext.go.jp/ja/5000/2011/10/5000_100602.pdf Toyama helicopter survey plan

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111007/0835_hosyasen.html As a result of the Tokyo and Kanagawa helicopter survey, levels higher than 0.2 μSv/h are found in Tokyo in part of the mountainous region of Okutama and at the border with Chiba prefecture in Katsushika ward. For Kanagawa, except some part of the mountainous region, all is below 0.1 μSv/h. According to the ministry of education and science, there are two routes, one in the west and one in the east, and the mountain regions have a higher level than surrounding areas due to the deposits in forests.

http://www.yomiuri.co.jp/science/news/20110908-OYT1T00890.htm "The [15000 TBq] estimate does not comprise Cs-134, so the total is even greater".

Another estimate of the sea release, was presented by a Japan Meteorological Agency team at a meeting of the Geochemical Society of Japan in Sapporo:

A total of 13,500 terabecquerels of radioactive cesium-137 is slightly more than 10 percent of that of the residual substance left in the northern Pacific after previous nuclear tests, according to the researchers.
http://mdn.mainichi.jp/mdnnews/news/20110914p2g00m0dm104000c.html

 

[Azby]

Try not to be too hard on a man who has been trying to fight against financial influence corrupting scientific surety. He is notable for many truths and many absences of truth discovered. His failings have likely to do more with his age and fear than an honest account of observation.

His failings have to do with a blatantly self-serving agenda. He's now selling radiation measurement sevices in Japan, with prices much higher than those charged by other labs :

[noparse]http://www.busbylab.com/%E9%A3%9F%E5%93%81%E6%A4%9C%E6%9F%BB/[/noparse]

And is also selling expensive "Busby Laboratories" brand vitamin supplements! "Devised by the noted radiation risk specialist Dr. Christopher Busby," for "detox against impurities in the body." If he actually said "for detox against radioactive contamination" he could be accused of fraud, so he just leaves it implied.

[noparse]http://www.4u-detox.com/[/noparse]

I thought it was a joke at first, and that the site had been hacked by a detractor. But it's genuine.

Has anyone seen Soderbergh's latest film, "Contagion"? Busby looks more and more like the blogger character Krumweide every day...

 

[swl]

Children who have been exposed will have to be monitored for two or more decades.

I wonder what children are to be "monitored."

Edit: see following post.

 

[Gary7]

Asahi Shinbun says that all kids in Fukushima prefecture who were under 18 at the time of the disaster (360,000 kids) will have lifetime thyroid testing.

http://www.asahi.com/special/10005/TKY201107240415.html

 

[tsutsuji]

erratum (as underlined):

http://mainichi.jp/select/weathernews/news/20111006dde012040008000c.html There are limits to how much you can decontaminate with pressure washers. Pr. Yamauchi of Kobe university tells about his findings at a building used for children after-school care in Fukushima city. Inside the building, the floor had 0.33 μSv/h, the beams had 0.52, and just below the ceiling, it was 0.72 μSv/h, and he understood that the radiation increased with the height. So he checked the roof, outside, and it was 1.79 μSv/h. The roof had been cleaned using a pressure washer, but the radiation could not be reduced more. He is afraid the roof must be changed. He says the goal is to create secure areas where the radiation inside buildings is as low as 0.05 μSv/h as it was before the accident. Pr Kodama of Tokyo university says that in a kindergarten in Minamisoma there were mini hot spots such as the roof (33 μSv/h) and below the slide (5~10 μSv/h). After cleaning it once, the roof's radiation was lowered by 50%. It will be difficult to bring it to the 0.5 μSv/h goal, he says. Probably the surface must be removed or the whole roof must be changed. Know-how from house construction companies is needed.

A full translation of the Mainichi article is now available at http://mdn.mainichi.jp/mdnnews/national/news/20111007p2a00m0na018000c.html

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111008/1140_america.html the United States lifts the 80 km zone that had been decided for the United States citizens living in Japan.

 

[Astronuc]

I wonder what children are to "monitored." It is my understanding that less than a single percent of the population exposed to elevated levels of Iodine-131 will be monitored in any way.

Children who were present in higher exposure areas, e.g., a "hot spot" near the village of Tsushima (Namie Precinct, Futaba District, Fukushima Prefecture) and at Hirusone (Namie Precinct, Futaba District, Fukushima Prefecture - 8 km to the east) with levels of up to 74uG/h recorded on the 28 & 29th March, should be monitored. Ref: http://www.postharvest.com.au/Fukushima_Radiation.htm

http://japanecho.net/cms/wp-content/uploads/2011/06/1022en_fig1.jpg
http://japanecho.net/311-data/1022/

http://www.mext.go.jp/english/incident/1303962.htm[/URL]


[url]http://www.nature.com/srep/2011/110907/srep00087/full/srep00087.html#/f3[/url]
[url]http://www.nature.com/srep/2011/110907/srep00087/pdf/srep00087.pdf[/url]

 

[tsutsuji]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111009/index.html 100% of Fukushima prefecture children (360,000 children below 18 years old as of 1 April) will receive their first thyroid medical examination by 2014. Then they will be checked every two years until they are 20 years old. Then they will be checked every five years. 150 children from Iitate, Kawamata and other places in the planned evacuation zone have had their first check on 9 October. Results are to be mailed about one month after each examination.

 

[clancy688]

Asahi Shinbun says that all kids in Fukushima prefecture who were under 18 at the time of the disaster (360,000 kids) will have lifetime thyroid testing.

http://www.asahi.com/special/10005/TKY201107240415.html

Just a thought that occurred to me:

As good as this precaution is, won't that give raise to a new generation of Hibakusha? I fear that those kids could be the target of bullying campaigns, since it's likely that they'll be spread all over Japan.

 

[NUCENG]

Just a thought that occurred to me:

As good as this precaution is, won't that give raise to a new generation of Hibakusha? I fear that those kids could be the target of bullying campaigns, since it's likely that they'll be spread all over Japan.

Based on Japanese social history that is possible, but the choice is between testing for thyroid cancer and risking social ostracism or not testing and possibly dying from an undiagnosed cancer that is highly treatable.

The survivors of Hiroshima and Nagasaki included large numbers of victims who had burn scars and other visible injuries. That will not be the case with the people exposed to radiation from Fukushima. Thyroid screening is non-invasive and would seem to be easily kept private. Further, I would hope that the Japanese have learned from the past. In any case, based on the lessons learned at Chernobyl, I would want my children tested.

 

[Bodge]

Strontium-90 Discovered in Yokohama City, 245 km from Fukushima I Nuke Plant

http://ex-skf.blogspot.com/2011/10/strontium-90-discovered-in-yokohama.html

“To convert from “per kilogram” to “per square meter”, Japan’s Nuclear Safety Commission uses the factor of 65.”

This equals over 12,500 Bq/m² of strontium-90 in Yokohama.

It's time to stop focussing on Iodine and Caesium - there are nastier isotopes around..

 

[Sorai]

Strontium-90 Discovered in Yokohama City, 245 km from Fukushima I Nuke Plant

http://ex-skf.blogspot.com/2011/10/strontium-90-discovered-in-yokohama.html

“To convert from “per kilogram” to “per square meter”, Japan’s Nuclear Safety Commission uses the factor of 65.”

This equals over 12,500 Bq/m² of strontium-90 in Yokohama.

The sample comes from dirt accumulated near a drain on the roof of a building. Using NSC's conversion factor for soil samples would not be accurate in this case. Actually you would have to divide by the total square meters of the roof and try to take into account how effective the drain was to get an idea of the fallout per square meter.

This is a previous EX-SKF post about the location in Yokohama (Kohoku-ku) where samples with high concentration (63 and 105 KBq/Kg) of radioactive cesium were obtained:
http://ex-skf.blogspot.com/2011/09/105600-bqkg-of-radioactive-cesium-from.html"

And this is a photo of the sampling location:
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It seems each portion of the roof is 6*3.7m, so around 22 square meters.