- 14 μSv/h from the yellow substance on the roof in Kashiwa Chiba (Fukushima Diary, Aug 10, 2012):
Around the end of July, I had the professional cleaners wash the roof of our house.
The roof was covered with something like this yellow moss. It was 0.7 μSv/h on its surface.
I took 20g of it by a kitchen knife. Radiation meter indicated it was red zone, 1.2 μSv/h.
I haven’t measured 1.2μSv/h from merely 20g of sample even around here known to be hotspot.
It was totally washed off after cleaning, radiation level was decreased a little bit, 0.4 μSv/h on the surface, but the yellow substance was still with mud in the rain gutter.
I took 3.6 kg of it with the perfect protective clothing (tyvek, gas mask, goggles, plastic gloves).
I packed the clothing soon after taking off the sample, had shower to clean eyes, ears, nostrils carefully.
This is very dangerous, please don’t do it. I can’t take a responsibility if something happened to you.
The radiation level was 14 μSv/h. I haven’t measured higher than 10 μSv/h before. It makes sense why the radiation level is high on the second floor.
– Professor Yukio Hayakawa Takes a “Radioactive Walk” In Abiko City and Kashiwa City in Chiba (EX-SKF, April 19, 2012):
The Gunma University professor took a walk in part of Abiko City and Kashiwa City, in the so-called “Tokatsu area” in the northwest corner of Chiba Prefecture with elevated radiation levels.
He says there is a statistically significant difference between the radiation levels on the ground levels and the levels at 1 meter off the ground, with the levels at 1 meter off the ground 20 to 30% less than at the ground levels.
The radiation levels of “black dust” he found along the way (in microsievert/hour):
Professor Hayakawa’s walk from Abiko City to Kashiwa-no-ha in Kashiwa City on April 16, 2012:
Professor Hayakawa went to Koriyama City in Fukushima Prefecture and walked in Kaiseiyama Park right near the City Hall. Compared to his walk in Edogawa-ku, Tokyo on the previous day, the radiation levels in Koriyama City is markedly higher (no surprise).
This time, the professor is armed only with his personal survey meter that only measures gamma ray. He seems to have a protective case on the survey meter, so I don’t think he is laying down the survey meter “naked” on the grass or dirt. (He’s been doing this for one year now in various locations, after all.)
He took the measurement of “black dust” at 4 locations:
- 3.533 microsieverts/hr
- 9.103 microsieverts/hr
- 7.291 microsieverts/hr
- 6.331 microsieverts/hr (in the City Hall parking lot)
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– 186 Bq/Kg from tap water in Kashiwa (Fukushima Diary, April 7, 2012):
A Japanese magazine reported they measured 186 Bq/kg from tap water in Kashiwa.
186 Bq/kg from tap water in Kashiwa Chiba (3/14/2012)
147 Bq/kg from tap water in Kashiwa Chiba (3/24/2012)
62 Bq/kg from tap water in Tokyo (3/14/2012)
31 Bq/kg from tap water after filtering in Tokyo (3/14/2012)
They used the dosemeter named JG22N. JG22N picks up beta ray and converted it into the energy of cesium 137.
It therefore might have picked up strontium, iodine, and tritium and converted it all to cesium 137.
Tritium has almost never been measured from tap water or rain though it acts exactly like water. Continue reading »
– 1.17μSv/h in Kashiwa Chiba (Fukushima Diary, Mar 19, 2012):
Just for reader’s information, at the check point of off-limits area, where is 30km area from Chernobyl, it is 0.4μSv/h.
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– Prof. Yukio Hayakawa’s Walk with his Survey Meter in Nagareyama-Kashiwa in Chiba Prefecture (EX-SKF, Feb. 19, 2012):
Radiation levels remain elevated in Kashiwa City in Chiba Prefecture. It was in Kashiwa that 450,000 becquerels/kg of radioactive cesium was found from the soil near the drain in the public space in the middle of the city. There is a strange (to me anyway) collaboration between the city and the citizen volunteers to decontaminate the city.
Before the Fukushima I Nuke Plant accident, the background radiation level in Kashiwa City must have been no higher than the average in Chiba, which was 0.03 microsievert/hour (see this site). Now, as Professor Hayakawa’s walk shows, it is 10 times that in many locations. Contrary to a belief by some in Japan that there was no radioactive plume that went south from Fukushima through Ibaraki to Chiba, Tokyo and Kanagawa, these elevated radiation levels in Kashiwa City are the evidence that the plume did in fact come.
And these hotspots are everywhere:
And here is Japan’s new way to deal with soil contamination …
… and it should get everyone’s attention, because this is GENOCIDE.
– Kashiwa govt wants help with hotspot (Daily Yomiuri, Oct. 28, 2011):
KASHIWA, Chiba–A radiation hotspot in Kashiwa has still not been decontaminated a week after radiation of 57.5 microsieverts per hour was recorded on a city-owned plot of land.
The city insists such a high level of radiation is beyond the level a local government can handle on its own, though it decided to conduct surveys to find other hotspots after many residents expressed anxiety over the issue.
The Kashiwa municipal government said last Friday that radiation of 57.5 microsieverts per hour had been detected about 30 centimeters below the surface of the plot of land. Its subsequent examination of soil at the location detected radioactive cesium of up to 276,000 becquerels per kilogram.
Airborne radiation of 2 microsieverts per hour was recorded one meter above the ground–the same level detected in Iitatemura, Fukushima Prefecture, which was designated part of the expanded evacuation zone after the beginning of the crisis at the Fukushima No. 1 nuclear power plant.
– Kashiwa City’s Radioactive Dirt: 276,000 Bq/Kg of Cesium (EX-SKF, Oct. 22, 2011):
The highly radioactive dirt in Kashiwa City in Chiba, which measured 57.5 microsieverts/hr 30 centimeters below the surface, was not from radium after all or any other nuclides that are used in industrial or medical use (some suggested cobalt-60, for example). It was from radioactive cesium.
On October 22 Kashiwa City announced the result of the analysis of three dirt samples from the location at different depth (one on the surface, two at 30 centimeter deep). The analysis was done on October 22. The unit is becquerels per kilogram: