NAGRA Opalinus Clay (…002 - Version 1
FEP 6.2.9 Effect of temperature on chemical processes

All chemical processes are temperature dependent. In particular, the kinetics and equilibrium position of chemical reactions and the different phases that may exist can be affected by temperature. If high temperatures exist (> 80 °C) for a period during the evolution of the repository, high-temperature cementitious phases may form, which give rise to uncertainty in the behaviour of the repository at later times. Based on modelling results, temperatures are expected to be well below 80 °C at all times.