Radionuclide Migration from a Fracture toward a Granite Matrix at the Josef Underground Laboratory

摘要

Crystalline rocks are being considered as potential host rocks for the construction of deep geological repositories (DGR) for radioactive waste in a number of European countries including the Czech Republic. Advection is considered as a main process within such a type of test. Tracer tests, using various substances, are used for a number of different purposes;;however, they are generally employed particularly for the characterisation of flow systems. A system consisting of a flow field intersecting a water bearing fracture was first identified at the Josef Underground Laboratory, whereupon two boreholes were drilled and fitted with instrumentation so as to determine and characterise an ideal location for the potential injection of a radioactive tracer into the fractured rock massif. A number of methods were employed in order to describe the rock system and the hydraulic flow field in detail prior to tracer injection. This was followed by the conducting of safety calculations aimed at providing a description of any potentially hazardous impacts on humans and the biosphere as required by the site licensing procedure.