Wednesday, April 24, 2013

#Fukushima fallout at Canadian embassy in Tokyo was 225,000 Bq/m² — Far in excess of limit set for radiation control zones

Study: Fukushima fallout at Canadian embassy in Tokyo was 225,000 Bq/m² — Far in excess of limit set for radiation control zones:
Title: The ambient gamma dose-rate and the inventory of fission products estimations with the soil samples collected at Canadian embassy in Tokyo during Fukushima nuclear accident

Source: Journal of Radioanalytical and Nuclear Chemistry

Author:  Weihua Zhang, Judah Friese, Kurt Ungar

Date: April 2013, Volume 296, Issue 1, pp 69-73
“The results have demonstrated that the significant volatile fission

products carried with aerosol were deposited on the ground by wet or

dry precipitation within 300 km around Fukushima plant. The actinide

data suggests that there was not a measurable amount of nuclear fuel

from Fukushima reactors present in this distance”
In this study, soil samples were collected at Canadian embassy in Tokyo (about 300 km from Fukushima) on 23 March and 23 May of 2011 for purposes of estimating concentrations of radionuclides in fallout, the total fallout inventory, the depth distribution of radionuclide of interest and the elevated ambient gamma dose-rate at this limited location. Some fission products and actinides were analyzed using gamma-ray spectrometry, alpha spectrometry and liquid scintillation counting. The elevated activity concentration levels of 131I, 132I, 134Cs, 137Cs, 136Cs, 132Te, 129mTe, 129Te, 140Ba and 140La were measured by the gamma-ray spectrometer in the first sample collected on 23 March. Two months after the accident, the 134Cs and 137Cs became only detectable nuclides. A mass relaxation depth of 3.0 g/cm2 was determined by the activities on the depth distribution of 137Cs in a soil core. The total fallout inventory was thus calculated as 225 kBq/m2 on March sampling date and 25 kBq/m2 on May sampling date.
Source: http://enenews.com/study-fukushima-fallout-at-tokyo-embassy-was-225000-bqm%C2%B2-exceeds-limit-set-for-radiation-control-zones