Development study on the geological database (II)

not registered; not registered; Ida, Toshio*; Fusaeda, Shigeki*; not registered; Katsurai, Kiyomichi*

This study has been carried out in order to increase the reliability of the performance assessment of geological isolation systems for high level wastes. We have been investigating a proper modeling of various phenomena, which would occur in the disposal environment and improving the reliability of geochemical data used in the performance assessment. The results are summarized as follows: (1)Quality assurance for geochemical data and modeling. We have compiled technical report, geochemical database (newest thermodynamic database), and calculation, conversion program for geochemical analysis, which supporting the second progress report. (2)Study on groundwater categorization and dominant reaction based on site data. We have carried out HCA/PCA analysis based on observed deep groundwater to support groundwater categorization of the second progress report. We concluded 3-type model groundwater categorized by analysis. (3)Experimental study on thermodynamic data of Se and Pd. It is confirmed that sulfate reduction bacteria do not exist in our experimental environment. (4)Planning on data acquisition for geochemical data of radioactive elements. Firstly we have pick up key radioactive elements and future studies based on the second progress report. Then we have draw up R&D plan for QUALITY. (5)Geochemical study on the long-term stability of backfill material. An extensive literature review was carried out about the effect of Iron on Bentonite stability. Experimental conditions are researched to develop thermodynamic and kinetic modeling. (6)Study on the technical geochemistry guideline of site selection for disposal. We have researched on the recommendation of sites for HLW (guideline of site selection) in foreign country and site selection from a view point of natural analogue. And we have summarized geochemistry technical guideline for site selection.