Synthesized research report in the second mid-term research phase; Mizunami Underground Research Laboratory Project, Horonobe Underground Research Laboratory Project and Geo-stability Project

Hama, Katsuhiro ; Mizuno, Takashi   ; Sasao, Eiji   ; Iwatsuki, Teruki  ; Saegusa, Hiromitsu; Sato, Toshinori  ; Fujita, Tomoo ; Sasamoto, Hiroshi   ; Matsuoka, Toshiyuki; Yokota, Hideharu; Ishii, Eiichi   ; Tsusaka, Kimikazu*; Aoyagi, Kazuhei  ; Nakayama, Masashi ; Oyama, Takuya ; Umeda, Koji; Yasue, Kenichi; Asamori, Koichi; Osawa, Hideaki  ; Koide, Kaoru; Ito, Hiroaki ; Nagae, Isako; Natsuyama, Ryoko; Semba, Takeshi ; Amano, Kenji  

We have synthesised the research results from Mizunami/Horonobe URLs and geo-stability projects in the second mid-term research phase. It could be used as technical bases for NUMO/Regulator in each decision point from sitting to beginning of disposal (Principal Investigation to Detailed Investigation Phase). High quality construction techniques and field investigation methods have been developed and implemented and these will be directly applicable to the National Disposal Program (along with general assessments of hazardous natural events and processes). It will be crucial to acquire technical knowledge on decisions of partial backfilling and final closure by actual field experiments in Mizunami/Horonobe URLs as main themes for the next phases.