An overview of the Canadian nuclear waste corrosion program

Abstract

Over the past decade, the Nuclear Waste Management Organization has conducted a thorough proof test plan (PTP) to evaluate their novel copper‐coated used fuel container and bentonite buffer box underground emplacement concept for use in a deep geological repository (DGR). This PTP has included the development of new technologies as well as feasibility studies related to engineered barrier production, underground emplacement, and safety assessment of the technologies within a DGR. Although the PTP was winding down in 2022, many work packages continue, particularly those associated with the evaluation of the corrosion performance of the used fuel container, the Nuclear Waste Management Organization (NWMO)'s copper corrosion allowance. This work evaluates the extent of corrosion that may result from oxic‐, radiolytic‐, anoxic‐, and sulfide‐induced corrosion which may occur in the Canadian DGR. Particular attention is paid to assessing the potential for localized corrosion phenomena across each project. This article provides an overview of these work packages which support a lifetime corrosion expectation of 270 µm and an extreme upper bound of corrosion of 1204 µm over one million years.