Considerations on Upscaling of Hydraulic and Transport Parameters for a Plastic Clay Formation

The report presents considerations from the point-of-view of different scientific disciplines on how to treat the upscaling of hydraulic and transport parameters measured in experiments using clay samples of a few centimetres to parameter values that are representative on the formation scale (several decametres) at the considered repository site, and this in the case of a plastic clay formation. The report is structured in three main parts. Chapter 2 discusses how microscopic flow and transport processes and characteristics can be upscaled to a scale corresponding to the thickness of a host clay formation. Chapter 3 treats the occurrence of fractures and fissures in a plastic clay formation and their possible impact on flow and transport. In formations where heterogeneities offer possibilities for accelerated water flow or transport, those heterogeneities can be important elements for the upscaling of the hydraulic and transport parameters. Chapter 4 discusses the heterogeneity of the Boom Clay formation and its impact on flow and transport characteristics for this formation.