Reversibility and Retrievability: An International Conference and Dialogue

Organised by the OECD Nuclear Energy Agency
Reims, France, 14-17 December 2010

Overview

On 14-17 December 2010, the OECD Nuclear Energy Agency (NEA) organised the International Conference and Dialogue on Reversibility and Retrievability in Planning Geological Repositories. Fifteen NEA member countries and two international organizations were represented. Over 180 policy makers, civil society stakeholders and experts from academia and from implementing and regulatory organisations explored the commonalities and differences between national waste management programmes as well as the various stakeholder expectations. Chaired by French MP Claude Birraux, this conference was the culmination of the Reversibility and Retrievability (R&R) project established in 2007 by the NEA Radioactive Waste Management Committee (RWMC).

The conference was hosted in Reims, France by the Agence nationale pour la gestion des déchets radioactifs (ANDRA), who played an important role in the development of the NEA International Retrievability Scale . This scale, published in a 4-page leaflet in English and in French, is recognized as an effective tool for promoting dialogue amongst interested parties. Conference proceedings will be published early in 2012. This international conference was the first in a decade on this subject, and the first ever to propose dialogue among such a wide range of stakeholders.

Among the key points that emerged are:

Development of any geological repository for radioactive waste will take place over many decades and should be open to progress in science and technology, to evolving societal demands and to fixing potential implementation errors. In this regard, selecting technologies that are as reversible as possible is a prudent approach. There is interest in a number of countries to show that retrieval of the waste is feasible during the period of waste emplacement or even during a certain period after closure of the repository.
While countries differ in their plans to study retrieval before or after closure of a repository, the Retrievability Scale developed by the NEA R&R project is a useful communication tool across contexts. It shows that even if geological disposal is intrinsically a reversible technology, ease of retrieval through the various stages of repository implementation can only be a matter of degree.
There is strong societal interest in reversibility of decisions or retrievability of waste, as indicated by legal provisions in many countries. In France, for instance, reversibility is at the core of the current technical and societal debate framed by its stepwise waste management process. There is universal agreement, however, that R&R provisions are never to interfere with long-term safety. R&R only add value to a final management solution that rests on passive safety.
Reversibility of decisions and retrievability of waste are complex subjects that cannot be considered in isolation from safety and societal issues. Further reflection and dialogue are needed, in particular to harmonise vocabulary and to define key terms such as "disposal", "storage", "waste" and "closure". Because there is no one-size-fits-all, each concept should be adapted to its national context.

Overall, Reversibility and Retrievability are tools which help implement repositories in a manner that is professional and responds to ethical and precautionary obligations. They add societal and technical value to repository development plans by helping to close down options in a considered manner. R&R practices are not essential to long-term safety, but provide extra assurance that long-term safety will be achieved. It was concluded at the conference that: "R&R are not a destination, but a path to be walked together".