[en] This reports represents (1) a data set related to the engineered barrier system and (2) the chemical environment in a real repository condition for later use in performance analysis of geologic disposal. The main results are as follows: 1) Considering the case of groundwater intrusion into a repository, data for glass waste form, overpack, and buffer materials were complied, some of which data were obtained by CRIEPI's activities. Appropriate data were chosen from the compilation and a data set for performance analysis was constructed. 2) Chemical environment in a repository was analysed by the geochemical simulation and the results indicated the neutral pH and reducing condition will be achieved. This is favorable for TRU elements to produce insoluble solids. 3) Hydrogen gas accumulation produced by overpack corrosion was discussed. Geochemical calculations suggest hydrogen gas pressure will not drastically be increased because of consumption of the hydrogen by the chemical reaction between hydrogen and bentonite as a buffer material. (author)