Enhancement of the methodology of repository design and post-closure performance assessment for preliminary investigation stage, 2; Progress report on NUMO-JAEA collaborative research in FY2012 (Joint research)

Shibata, Masahiro ; Sawada, Atsushi ; Tachi, Yukio  ; Hayano, Akira  ; Makino, Hitoshi ; Wakasugi, Keiichiro; Mitsui, Seiichiro  ; Oda, Chie  ; Kitamura, Akira  ; Osawa, Hideaki  ; Semba, Takeshi ; Hioki, Kazumasa ; Kamei, Gento ; Kurosawa, Susumu*; Goto, Junichi*; Shibutani, Sanae*; Goto, Takahiro*; Ebashi, Takeshi*; Kubota, Shigeru*; Inagaki, Manabu*; Moriya, Toshifumi*; Suzuki, Satoru*; Oi, Takao* ; Ishida, Keisuke*; Nishio, Hikaru*; Ichihara, Takayuki*; Ishiguro, Katsuhiko*; Deguchi, Akira*; Fujihara, Hiroshi*

Following FY2011, JAEA and NUMO have conducted a collaborative research work which is designed to enhance the methodology of repository design and performance assessment in preliminary investigation stage. With regard to (1) study on rock suitability in terms of hydrology, the tree diagram of methodology of groundwater travel time has been extended for crystalline rock, in addition, tree diagram for sedimentary rock newly has been organized. With regard to (2) study on scenario development, the existing approach has been improved in terms of a practical task, and applied and tested for near field focusing on the buffer. In addition, the uncertainty of some important processes and its impact on safety functions are discussed though analysis. With regard to (3) study on setting radionuclide migration parameters, the approaches for parameter setting have been developed for sorption for rocks and solubility, and applied and tested through parameter setting exercises for key radionuclides.