Enhancement of the methodology of repository design and post-closure performance assessment for preliminary investigation stage, 3; Progress report on NUMO-JAEA collaborative research in FY2013 (Joint research)

Shibata, Masahiro ; Sawada, Atsushi ; Tachi, Yukio  ; Makino, Hitoshi ; Wakasugi, Keiichiro; Mitsui, Seiichiro  ; Kitamura, Akira  ; Yoshikawa, Hideki; Oda, Chie  ; Ishidera, Takamitsu ; Suyama, Tadahiro; Hatanaka, Koichiro; Semba, Takeshi ; Seo, Toshihiro ; Kamei, Gento ; Kurosawa, Susumu*; Goto, Junichi*; Shibutani, Sanae*; Goto, Takahiro*; Kubota, Shigeru*; Inagaki, Manabu*; Moriya, Toshifumi*; Suzuki, Satoru*; Ishida, Keisuke*; Nishio, Hikaru*; Makiuchi, Akie*; Fujihara, Hiroshi*

JAEA and NUMO have conducted a collaborative research work which is designed to enhance the methodology of repository design and post-closure performance assessment in preliminary investigation stage. With regard to (1) study on rock suitability in terms of hydrology, based on some examples of developing method of hydro-geological structure model, acquired knowledge are arranged using the tree diagram, and model uncertainty and its influence on the evaluation items were discussed. With regard to (2) study on scenario development, the developed approach for "defining conditions" has been reevaluated and improved from practical viewpoints. In addition, the uncertainty evaluation for the effect of use of cementitious material, as well as glass dissolution model, was conducted with analytical evaluation. With regard to (3) study on setting radionuclide migration parameters, based on survey of precedent procedures, multiple-approach for distribution coefficient of rocks was established, and the adequacy of the approach was confirmed though its application to sedimentary rock and granitic rock. Besides, an approach for solubility setting was developed including the procedure of selection of solubility limiting solid phase. The adequacy of the approach was confirmed though its application to key radionuclides.