Improvement of the resuspension model for OSCAAR using the atmosphere-soil-vegetation model SOLVEG-R (Contract research)

Nakanishi, Chika*; Ota, Masakazu  ; Hirouchi, Jun ; Takahara, Shogo  

The OSCAAR program is a probabilistic risk assessment program for reactor accidents developed by Japan Atomic Energy Agency. To improve the model included in the OSCAAR program, which is about long-term exposure caused by the resuspension of radioactive materials deposited on soil surfaces, we calculated resuspension factors for Cs-137. The one- dimensional atmosphere-SOiL-VEGetation model, SOLVEG-R was utilized to compute resuspension factor. The wind velocity was kept constant in this study since it significantly affects particle resuspension behavior. Our calculations indicate that wind velocities below 6 m s resulted in little variation in the annual mean resuspension factor at a height of 1 m. However, as wind velocities increased above 6 m s, the resuspension factor significantly increased. The resuspension factors ranged from 10 to 10 m for wind velocities ranging from 1 m s to 7 m s.