Exposure dose assessment associated with decommissioning of the trench disposal facility in Nuclear Science Research Institute, 2; Dose assessment based on exposure scenarios at the time of application for business licenses and the new regulatory standards

Sasaki, Kazuki; Sato, Yoshiyuki; Aoyama, Airi; Ishimori, Kenichiro ; Abe, Daichi*; Sugaya, Toshikatsu; Amazawa, Hiroya; Sakai, Akihiro ; Iseda, Hirokatsu

Japan Atomic Energy Agency is carrying out a field test for trench disposal of very low-level radioactive waste generated from dismantling first Japanese demonstration reactor named Japan Power Demonstration Reactor. This disposal facility is scheduled to become the first near-surface one in Japan to start decommissioning in 2025. This presentation represents results of periodic review before decommissioning. Based on the setting of the condition of the disposal site and surroundings in (1), assessments in this presentation (2) were conducted in two ways: technical standards when obtaining the business licenses and new regulatory standards enforced in 2013. These resulted in below standard values. This means the disposal facility needs no additional exposure protection and is possible to move to decommissioning.