Estimation of the release time of radio-tellurium during the Fukushima Daiichi Nuclear Power Plant accident and its relationship to individual plant events

福島第一原子力発電所事故後の放射性テルル放出時間の推定及びそれらと個々のプラント事象との関係

高橋 千太郎*; 川島 茂人*; 日高 昭秀   ; 田中 草太*; 高橋 知之*

Takahashi, Sentaro*; Kawashima, Shigeto*; Hidaka, Akihide; Tanaka, Sota*; Takahashi, Tomoyuki*

A simulation model was developed to estimate an areal (surface) deposition pattern of Te after the Fukushima Daiichi Nuclear Power Plant accident, and by using this model, timing and intensity of the release of Te were reversely estimated from the environmental monitoring data. The validation using data for Cs showed that the model simulated atmospheric dispersion and estimated surface deposition with relatively high accuracy. The estimated surface deposition pattern of Te was consistent with the actually measured one. The estimated time and activity of Te emission seemed to indicate that the Te was emitted mainly from Unit 3.