Reversibility of Decisions and Retrievability of Radioactive Waste: An Overview of Regulatory Positions and Issues

The Radioactive Waste Management Committee (RWMC) of the NEA has been at the forefront worldwide in examining the topic of Reversibility and Retrievability (R and R). As early as 2001, an NEA survey-based report entitled 'Reversibility and Retrievability in Geological Disposal of Radioactive Waste' provided an overview of R and R by an ad-hoc group of experts from 11 NEA Member countries. The 2001 report (NEA 2001) observed that national safety regulations dealt mainly with operational safety and design targets for long-term (post-closure) safety and relatively little consideration was given to retrievability/reversibility or its implications. Yet, policy frames saw benefits from retrievability. In 2007, the RWMC launched the NEA R and R project with participation from 15 countries and two international organisations. The project included, amongst its members, representatives of six organisations involved in regulation, five regulatory authorities of five countries and one technical support organisation to the safety authorities. The project aimed to improve awareness amongst the RWMC constituency of the breadth of issues and positions regarding the concepts of R and R with the goal of providing a neutral overview of relevant issues and viewpoints in OECD countries. Hence substantial attention was given to R and R regulatory issues mainly in the context of decision making for repository development. The report (NEA 2011) points out regulatory issues, including safety criteria and licensing considerations. The present document presents an overview of findings, positions, boundary conditions and issues based on the results of the R and R project of 2007-2011 (stepwise decision making and reversibility, regulatory authorisations and R and R, decision making for retrieval) and of the Reims conference of December 2010 (terminology and definitions, legal and policy context, motivations for R and R, practical aspects, stakeholders confidence aspects)