Measurement of gamma dose rate and beta-gamma contamination・・・
The dose-rate results ranged from 2-160 microsieverts per hour・・・
a typical natural background level of around 0.1 microsieverts per hour.
High levels of beta-gamma contamination have been measured between 16-58
km from the plant.・・・
We have no contamination measurements showing that that contamination
levels are high at greater distances than 58 km from the plant, but this
cannot be excluded.
http://www.iaea.org/newscenter/news/tsunamiupdate01.html

０３・２１・２０１１

Japanese authorities have reported that they will measure radioactivity in the marine environment around the Fukushima Daiichi nuclear power plant. The monitoring will be conducted from 22-23 March by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). Sea water sampling from eight locations will be sampled and analysed by the Japan Atomic Energy Agency (JAEA), and results will be provided on 24 March. The analysis will include radionuclide concentrations found in sea water and dose rate. The IAEA will continue to follow this information.

TVニュースでは、「福島県双葉郡浪江町内で・・・」と言ってたようだ。

文科省測定で、周りより高い値の140〜150マイクロSv/hが、測定されていた地点【32】が、この浪江町内にある。伊達や福島と、原発との真中あたりだ。

「福島第一原子力発電所の20Km以遠のモニタリング結果の推移」（文科省）
http://www.mext.go.jp/component/a_menu/other/detail/__icsFiles/afieldfile/2011/03/22/1303995_2210.pdf

その地点だけが、なぜか高い値だ。