Ceramics as alternative solutions for the geological disposal of high‐level radioactive waste: Andra's R&D program

Abstract The concept of a safe geological disposal facility designed to manage radioactive waste is on the basis of the multibarrier system comprising both the host rock and various engineered barriers. The robustness of the latter depends directly on the building materials used. With specific regard to high‐level waste, Andra's Cigéo project includes, among others, two barriers, i.e., the disposal container and the microtunnel liner. A scenario was built and shows that safety requirements are satisfied using of low carbon steel for these two components. However, to further increase safety margins and simplify the operation of the facility, Andra decided to study other materials less prone to corrosion. Consequently, Andra launched an R&D program to assess the technical feasibility of a high‐level waste container and a microtunnel liner made from ceramics, with the technical characteristics needed to meet safety requirements. This document describes the current situation for these activities and suggests ways this objective can be met.