On the Theory of Transport of Fluids in Fractured Media for the Safety Analysis of a Nuclear Waste Repository

A systematic theory is developed of the role of fractures in the transport of radionuclides by groundwater through fractured rocks from the nuclear waste repository to be built in deep geologic formations to the biosphere. Fractures are grouped into four “irreducible” types: joints, nodes, shear zones, and fracture zones, and their geometrical and sorption characteristics, having bearings on radionuclide transport, are expressed in mathematical terms. The question of radioactivity retention in various fracture types is then carefully studied using idealized geometries to mimic natural forms. Fundamental transport equations are derived for the fracture-pore complex, taking into consideration the special physical characteristics of fractures and the effects of sorption therein.