Bobby1 posted this find at his blog http://optimalprediction.com/wp/too-tired-for-links-why-do-trusted-pundits-lowball-fuku/#comments
950 MICRO SIEVERT PER HOUR IN MINAMISOMA, FUKUSHIMA PREFECTURE, BLACK POWDER
[Translated excerpt] Black powder (statement, Sat-black substance) from 950 micro sievert per hour seems to be detected in Minamisoma, Fukushima Prefecture. You can not simply compare and black powder found in Edogawa-ku, Tokyo, Kashiwa, Chiba, and, it is not enough to become a high number of comparisons.http://portirland.blogspot.jp/2012/09/kuroikona-fukusimaken-minamisoumasi.html
Majia here: I used Google translate to examine the original post. There is no definite way to verify the information, but it certainly raises questions.
There is other evidence that black soil being found in areas of Japan is highly contaminated:
In June of 2012, reports of highly radioactive black soil began appearing in Japan. On June 14 the Asahi Shimbun ran a story addressing the soil:[i]
The highest level of radioactivity detected--about 5.57 million becquerels per kilogram--came from black soil collected in the Kanaya neighborhood of the Odaka district of southern Minami-Soma. In 36 out of 41 locations in Fukushima Prefecture where black soil was collected, the radioactivity level exceeded 100,000 becquerels per kilogram. If that level was found in incinerator ash, it would have to be handled very carefully and buried in a facility that had a concrete exterior separating it from its surroundings.
Citizens concerned about the highly radioactive soil brought samples to Tomoya Yamauchi, an academic specializing in radiation measurement. Yamauchi found that the soil contained radioactive cesium at levels of 1.08 million becquerels per kilogram. Other samples of soil brought in from Minami-Soma contained plutonium and strontium. Tokyo also yielded samples of highly radioactive soil. Despite the high levels of radiation, the article reported that no action was being taken to remove the soil:
But for now, nothing is being done about the black soil with high levels of radiation. "Because it normally is found on the ground, we believe it is not something that will have immediate effects on human health," a Minami-Soma municipal government official said.
No “immediate effects on human health” has become an often chanted mantra.
[i] Shoji Nomura. Radioactive 'black soil' patches: A scourge or a solution? Asahi Shimbun Weekly Area (2012, June 14), http://ajw.asahi.com/article/0311disaster/fukushima/AJ201206140067