It's the same researcher who said several thousand becquerels/kg of neptunium-239 was found in the soil in Iitate-mura, about 35 km northwest of Fukushima I Nuclear Power Plant. It seems it's not just Iitate-mura that got doused with neptunium, which decays into plutonium. Date City, about 25 km northwest from Iitate-mura and 60 km from Fukushima I Nuclear Power Plant, also got a large amount of neptunium.
To recap, uranium-239, whose half life is about 24 minutes, decays into neptunium-239 with a half life of about 2.5 days, which then decays into plutonium-239 whose half life is 24,200 years.
Again, the reason for withholding the information is explained in the article below as "the research paper being peer-reviewed by a foreign scientific journal" - a make-or-break event, apparently, for a young researcher at a prestigious university in Japan - and as precaution against the possible Japanese government action to squash the information. The article was written by the same husband & wife comedian couple who first wrote about neptunium in Iitate-mura on their blog magazine in early August.
I'm sure the nuclear experts who have appeared on TV to soothe the populace ever since the March 11 nuclear accident has the good explanation for neptunium-239 in these locations. They've kept saying "No way plutonium will be found outside the compound, because it is heavy and it doesn't fly". Oh I get it. It's plutonium they were talking about, not neptunium which decays into plutonium. My bad.
From Nikkan SPA September 13 issue (part on Date City only):
The email began thus:
"I heard it directly from a university researcher whose specialty is radiation measurement. Neptunium, the nuclide that decays into plutonium, flew at least to Iitate-mura and Date City in large quantity. The current survey method focuses only on gamma ray, and all it detects is radioactive cesium. The real danger is alpha-nuclides, which continues to be ignored. Iitate-mura may be being betrayed again..."
The article by the comedian cum independent journalist couple continues and says this person attended a lecture given by this researcher.
It still doesn't make sense to me that the information already freely given at a public lecture has to be withheld because of the peer-review process, but oh well.
Date City by the way has been selected by the national government to conduct "decontamination" experiments. So is Iitate-mura. They are using high-pressure spray washers to blast roofs, sidings and roads, and digging up the soil. Plutonium? What plutonium?
Unlike Iitate-mura, though, almost all residents in Date City still live within the city. Even those who are ordered to move because of high radiation level in their homes have moved to temporary housing that the city has provided, within the city.