Atmospheric dispersion simulation of radionuclides in the Eastern Japan region discharged from the Fukushima Daiichi Nuclear Power Plant by WSPEEDI-II

Terada, Hiroaki   ; Nagai, Haruyasu  ; Katata, Genki; Furuno, Akiko   ; Nakayama, Hiromasa   ; Chino, Masamichi

To make a contribution to dose assessment of residents and understanding of the formation mechanism of contamination distribution due to the Fukushima Daiichi nuclear accident, we conducted an atmospheric dispersion analysis by using Worldwide version of System for Prediction of Environmental Emergency Dose Information, WSPEEDI-II. The source conditions of released radionuclides we used in our model calculations were based on the tentative values which had been announced by the Nuclear Safety Commission (NSC) of Japan on April 12 and published in Chino et al. (2011). We examined the validity of estimated release rates of radionuclides and model reproducibility for environmental monitoring data such as air dose rate and daily fallout which was measured throughout Japan and announced by the Ministry of Education, Culture, Sports, Science and Technology (MEXT).