Interactions between Carbon Steel and Uo2 Corrosion Fronts inside a Failed Nuclear Waste Container

The corrosion of carbon steel in the chloride-dominated groundwaters anticipated inside a failed spent fuel waste container has been studied in the presence of small concentrations of added hydrogen peroxide. Solutions with peroxide concentrations in the micro-molar range were found to accelerate steel corrosion slightly leading to the formation of Fe-containing corrosion product deposits but not to passivation of the steel. Calculations using a model for fuel and steel corrosion inside a failed waste container show that peroxide concentrations at the steel surface should be many orders of magnitude less than these micromolar levels. It can be concluded that the redox scavengers, Feand H2, produced by the active corrosion of the steel, will be available to suppress the radiolytic corrosion of the fuel and to avoid the associated radionuclide release processes.