Monthly deposition samples were collected at the Nuclear Fuel Cycle Engineering Laboratories located about 115 km south of the Fukushima Daiichi Nuclear Power Plant (NPP), and the radioactive nuclides were analyzed. Although radionuclides such as
131I,
129mTe-
129Te and
132Te-
132I with
134Cs and
137Cs were observed by gamma spectrometry at the early time of the Fukushima Daiichi NPP accident, only
134Cs and
137Cs were detected as of September 2011. The annual depositions of
134Cs and
137Cs were about 19,000 and 17,000 Bq m
-2, respectively in March 2011-February 2012 after the accident. Moreover,
90Sr was detected in some samples. Monthly
90Sr deposition in March 2011 was 5.1 Bq m
-2 month
-1 and then decreased after that. On the other hand,
239, 240Pu concentration was the same level with the concentration before the accident.
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