Site Selection for a Geological Disposal in France: An Approach of Convergence

On December 1991, the French National Assembly passed the French Waste Management Research Act, authorizing a 15 year research program of three options for HLW: separation and/or transmutation, long-term storage, and geologic disposal. On June 2006, the “Planning Act on the sustainable management of radioactive materials and waste” sets a new framework and new aims to the above mentioned options. This paper deals only with the geologic disposal research program. In a step by step approach, this program has been broken down into three phases having intermediate goals (objectives): site selection for an Underground research Laboratory (URL), potential disposal feasibility, potential reversible disposal design. The first step of the research program aimed at URL site selection. From 1994 to 1996, Andra carried out geological-characterization work in four districts. This enabled to make the Request for Licensing and Operation of the laboratory facility on three sites. During this phase, wells, 2D seismic campaigns and land studies of geologic outcrops were the essential activities. The result was the selection of the most suitable site for the implementation of an underground laboratory. Main results on Bure URL will be presented in the paper. In the second phase the research program targeted the safety and technical feasibility of a potential reversible disposal somewhere in Meuse and Haute Marne districts site, chosen by the government in 1998. Andra conducted geologic survey during the URL shaft construction and experiments in drifts at depths of 445 and 490 m. This program allowed consolidating the knowledge already acquired: geological environment, stability of the rock, containment properties and it confirms that the rock will maintain its qualities. The 2005 Progress Report presents the results of this phase. The main conclusion is that a potential disposal facility may be safely constructed over a zone around the URL, called transposition zone (about 250 km²). The paper will present the most important results in this phase. From 2006, the third phase of the program, the activities were oriented, inside the transposition zone, to determine a smaller zone in which a potential disposal facility could be designed. In 2009, Andra issued a proposal describing such a zone to the French authorities. In this paper, the main results of this phase will be presented. Finally, the next steps towards a final implementation will be given.