[1F14-19] Fuel Debris 3

[1F19] Assessment of dust dispersion data for future safety analysis of Fukushima Daiichi fuel debris retrieval

(14) Basic study of safety assessment regarding airborne dust release during fuel debris retrieval

*Michiya Sasaki¹, Tadafumi Koyama¹, Takatoshi Hattori², Koichi Uozumi¹, Kinya Nakamura¹, Taizo Kanai¹, Kenta Inagaki¹, Shun Kanagawa¹, Takatoshi Hijikata¹, Tetsuya Kato¹ (1. CRIEPI, 2. NDF)

Keywords:fuel debris, dust , dispersion, safety assessment

In the safety assessment of fuel debris removal, it is necessary to consider not only internal exposure by inhalation for the member of the public at off-site in case of an accident, but also internal exposure for the member of the public and radiation workers due to dust dispersion, and external exposure for radiation workers due to dust accumulation in pipes and filters during normal operation. In this study, we attempted to clarify the parameters and technical issues for the safety assessment of fuel debris removal with reference to the five-component linear equation method, which is used to assess public exposure in the event of an accident. In addition, we attempted to estimate the activity release by examining the safety assessment method for each step in the debris removal process under normal conditions, and for several scenarios assumed in case of an accident.