Modeling of Radiolytic Production of Oxidants Relevant to Corrosion of a Used Fuel Container in Deep Geologic Repository Environments

Abstract

The Canadian used nuclear fuel disposal concept involves a deep geologic repository (DGR) using a multi-barrier system. A key barrier is the copper-coated steel used fuel container (UFC). Relative to other design concepts, coated containers have thinner walls that will provide less shielding for γ-radiation, raising the possibility of radiolysis-induced corrosion. This work presents a chemical kinetics study on the gamma-radiolysis of environmental conditions anticipated in DGR. Humid air radiolysis produces nitric acid as the dominant oxidizing species at a concentration that increases linearly with dose rate.