Modelling performed using the PHREEQC and PHREEQC-TRANS codes

Honda, Akira; Inagaki, Manabu; Yamaguchi, Kohei; Walker, C.

This report was made as part of LCS (Long-term Cement Studies) that was an international project involving NAGRA, NDA, POSIVA and JAEA. A part of the in-situ experiment at Grimsel test site and the bench mark analysis in phase 1 is published in this report. In the bench mark analysis of the cement hydration reaction, there is a reasonable agreement between the measured and the predicted species in solution in terms of general trends being reproduced by the models produced by the three modelling groups. In the bench mark analysis of the chemical reaction of the granite in the environment with transportation and the high pH solution, the major trends in measured species concentrations could be reproduced by all models. The observed permeability profile could not be matched.