Risk Of Glacier Erosion On Underground Repositories
Free (open access)
R. Pusch, R. Adey & E. Santana-Diaz
Underground repositories are being considered for the storage of nuclear and toxic waste. These wastes are active for very long time scales during which significant geological events may take place such as glaciation which have the potential to disturb the repository and release the hazardous waste into the environment. This paper describes a numerical study to assess the risk. The literature provides data that indicate possible erosion depths of many tens of meters and even 100 to 200 m, which can have a significant impact on the stress state and hydraulic performance of the rock. An initial numerical model of glacial erosion showed that advancing glaciers can cause erosion to at least 180 m depth but a parameter study should be made for arriving at safe conclusions concerning erosion depths. 1 Introduction Glacier-generated erosion of major fracture zones appears to be a real process in nature as concluded from the literature. It provides data that indicate possible erosion depths of many tens of meters and even 100 to 200 m, which would have a significant impact on the stress state and hydraulic performance of the rock. No particular glacier types are considered in the study which is directed to general estimation of the attack on the bedrock by an advancing front of a land ice. An important part of the work has been to define the shape and properties of large ice masses for selecting boundary conditions and rock and ice parameters for numerical calculations.