Archaeological analogs and the future of nuclear waste glass

Abstract

Nuclear energy produces long-lived radioactive waste. Glass containment matrices are used to stabilize such waste and to prevent radionuclide dispersion. Over the past few decades, phenomenological models have been developed to predict the long-term behavior of these materials in anticipation of disposal in a deep geological formation. But considering the geological time scales necessary for radioactive decay validating these models is a challenge. Here we show how the validation of the predictive capacity of a mechanistic model applied to archaeological glass alteration bridges the gap between the short-term laboratory data and the long-term evolution of natural system in complex environment. This model applied to nuclear glass provides reliable uncertainties on long-term alteration rates and demonstrates that present models used in the safety calculations are conservative.