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Professor Yukio Hayakawa’s Radiation Contour Map of the Fukushima I Nuke Plant Accident, Ver 7:

Translated by EXSKF Blog

FRIDAY, SEPTEMBER 28, 2012

 

“The dates and times of contamination that I have just explained above do not coincide with the dates and times of explosions that took place at Fukushima I Nuclear Power Plant. Unit 1 exploded at 3:36PM on March 12, and Unit 3 exploded at 11:01AM on March 14. However, it wasn’t at these moments when a large amount of radioactive materials leaked from the plant.Instead, the release of radioactive materials into the atmosphere seems to coincide well with the drop in the reactor pressure.”

 

He made this observation in the latest version (7th) of his Radiation Contour Map released in July, before the Fukushima prefectural government sheepishlypublished the data from the monitoring posts in Fukushima taken in March last year, which does show the spikes in radiation in locations in Fukushima Prefecture not after the explosions but after the change in the reactor pressure after the vent.

Image
Professor Hayakawa of Gunma University first put up his hastily charted map on the Internet on April 8, 2011, after the Fukushima prefectural government announced the result of the radiation measurement in schools and kindergartens inside Fukushima. The first version of the map was released on the net on April 21, 2011. I remember seeing it, and also remember he was attacked for “fear-mongering”. It was around that time that Iitate-mura was officially designated as “planned evacuation zone”.

[…]

This map shows the dose rates of locations where radioactive materials that fell on the ground surface in March 2011 remain undisturbed. The values are as of September 2011, in microsievert per hour (μSv/h) at 1 meter off the ground surface of either turf or grass land. Radioactive materials get washed away from the dirt or asphalt surface by wind and rain, so the dose rates on these surfaces tend to be lower than what’s shown on the map. On the other hand, radioactive materials accumulate in rain gutters, on the ground under the roof overhang, in side drains, and on the side of the roads, resulting in the dose rates several times higher than what’s shown on the map.

[…]

What determined the distribution of radiation contamination was the wind. Volcanic ashes from the volcanic eruption are transported by the wind at a high altitude of several kilometers and higher. However, radioactive materials leaked from the Fukushima I Nuclear Power Plant were transported by the wind near the ground surface. Looking at the meteorological data from that time period, wind directions at an altitude of 1 kilometer and higher cannot explain the distribution. I believe radioactive materials were carried by the surface wind whose altitude was dozens of meters off the ground at most. That’s the reason why the isopleths of radiation seem to follow the ups and downs of geography, such as basins and mountain sides.

The radioactive cloud that passed over Minamisoma City in Fukushima Prefecture at 9PM on March 12 continued past over Sendai Bay and reached Onagawa-cho in Miyagi Prefecture at 2AM on March 13.

The contamination on March 15 was the worst. The radioactive cloud that passed over Iwaki City in Fukushima Prefecture at 4AM reached Kanto Plain at 6AM. Since it was not raining, the cloud then headed west and north until it hit the mountainous regions in Kanto and northern part of Gunma and Tochigi Prefecture, where, for the first time, it rained, and radioactive materials came down on the ground with the rain. The contamination of Fukushima Nakadori (middle third) also happened on that day. Radioactive materials that crossed the Abukuma Mountains came down with the snow. In the afternoon, a particularly dense radioactive cloud was spewed from the nuclear plant. Carried by the wind, it went straight in the northwesterly direction, and contaminated the areas all the way to Iitate-mura, which the cloud hit at 6PM.

In the evening of March 20, areas near the Miyagi-Yamagata border and southern Iwate were contaminated. Then, the wind turned south, sending the cloud past Mito City in Ibaraki Prefecture at 6AM on March 21, and reaching Shinjuku, Tokyo at 9AM. For 3 days from March 21 to 23, the Kanto region had heavy, intermittent rains. Moderate contamination seen in the eastern part of the Tokyo Metropolitan region is from this time period.

[…]

Just below the chronological contamination chart, Hayakawa has an interesting map plotting the radioactive density (cesium) of fly ashes from the incinerators. Why is he interested in measuring ashes, “dirt on the roadside” (that’s Hayakawa’s way of calling what others have called “black dust”), and gutters where radiation levels are high? He answers, “First, in locations far away from the plant, you can clearly see the extent of contamination by measuring them. Second, by identifying them, you can clean them effectively.” It looks he plotted the highest measurement found in these locations.

[…]

If you only view it digitally, you can download it at his blog, or at the links here:

Front page(pdf 5.5MBjpg 3.3MB
Back page (pdf 8.7MBjpg 2.7MB

 

http://ex-skf.blogspot.co.uk/2012/09/professor-yukio-hayakawas-radiation.html

 

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September 28, 2012 - Posted by | Uncategorized

6 Comments »

  1. […] the official map does not note any Cesium-137 contamination in the Tokyo metropolitan area, unlike an unofficial survey done at about the same time by Professor Yukio Hayakawa of Gunma University. Given the fact that the Japanese government and TEPCO denied for two months that any meltdowns had […]

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  2. […] official map does not note any Cesium-137 contamination in the Tokyo metropolitan area, unlike an unofficial survey done at about the same time by Professor Yukio Hayakawa of Gunma University. Given the fact that the Japanese government and TEPCO denied for two months that any meltdowns had […]

    Pingback by Implications of Fukushima Cesium for Japan | FukushimaFAQ.info | August 26, 2014 | Reply

  3. […] the official map does not note any Cesium-137 contamination in the Tokyo metropolitan area, unlike an unofficial survey done at about the same time by Professor Yukio Hayakawa of Gunma University. Given the fact that the Japanese government and TEPCO denied for two months that any meltdowns had […]

    Pingback by The Implications of The Massive Contamination of Japan With Radioactive Cesium | March 18, 2015 | Reply

  4. […] the official map does not note any Cesium-137 contamination in the Tokyo metropolitan area, unlike an unofficial survey done at about the same time by Professor Yukio Hayakawa of Gunma University. Given the fact that the Japanese government and TEPCO denied for two months that any meltdowns had […]

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  5. […] the official map does not note any Cesium-137 contamination in the Tokyo metropolitan area, unlike an unofficial survey done at about the same time by Professor Yukio Hayakawa of Gunma University. Given the fact that the Japanese government and TEPCO denied for two months that any meltdowns had […]

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  6. […] the official map does not note any Cesium-137 contamination in the Tokyo metropolitan area, unlike an unofficial survey done at about the same time by Professor Yukio Hayakawa of Gunma University. Given the fact that the Japanese government and TEPCO denied for two months that any meltdowns had […]

    Pingback by The Implications of The Massive Contamination of Japan With Radioactive Cesium | geoengineeringcrimes | May 13, 2016 | Reply


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