Published online by Cambridge University Press: 26 February 2011
The Project Gewähr 1985 (PG'85) safety analysis considered the practicality of HLW disposal in the crystalline bedrock of Northern Switzerland. More recently, an alternative disposal option in the argillaceous sediments overlying the crystalline basement has been examined. This paper examines some aspects of the performance of the near-field engineered barriers in an argillaceous environment, with specific comparison to the PG'85 crystalline case. Two phenomena are considered in particular detail: oxidation of the host rock during the operational phase and the related failure mode of the steel tunnel liner.