Site Selection Process for a HLW Geological Repository in France

Abstract

On December 1991, the French National Assembly passed the French Waste Management Research Act, authorizing and initiating a 15 year research program along three options for HLW long term solution: 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, each having intermediate objectives: site selection for an Underground research Laboratory (URL), disposal feasibility demonstration, reversible disposal design.

The first step of the research program aimed at URL site selection. From 1994 to 1996, Andra carried out geological characterization surveys in four French districts, leading to the Request for Licensing and Operation of laboratory facilities on three sites. During this phase, boreholes, 2D seismic campaigns and outcrops geologic studies were the main sources of data. The result was the selection of Bure area, 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 reversible disposal site, located in Meuse or Haute Marne districts, as selected by the government in 1998. Andra conducted geologic survey during the URL shaft sinking 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 and the regional geology, and containment properties. 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 with geological characteristics similar to those investigated at 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 located. In 2009, Andra issued a proposal for 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 described.