No abstract available

No abstract available

[en] One of the three sites under study by ANDRA is located on the Poitou shoal in the Vienne Department. The granitic basement rock is overlain by a 160 m thick layer of Jurassic sediments containing two seasonally pumped aquifers. The preliminary hydrogeological model of the granitic basement assumed that regional flow is SE-NW, and circulates in the hecto-metric fractures, and that groundwater flow velocity is very low. A preliminary performance assessment exercise focusing on the geological barrier was carried out based on these assumptions and a disposal concept where radwaste is stored in separate granodiorite 'blocks' delimited by the water-bearing fractures. As regards of the granodioritic blocks, the programme goals include analysing of detailed structure, obtaining uncontaminated samples of interstitial ground water in order to determine its physicochemical properties and evaluating transport and retention parameters. (author)

[en] The dossier on disposal Feasibility Assessment in Meuse/Haute-Marne, which was submitted by ANDRA to the French Government in June 2005, is the result of a long way from the Preliminary Geo-scientific Survey in 1994 to the Safety Case. An iterative approach was used, three iteration loops were organised between acquisition of knowledge, architecture and design, safety studies and analysis with milestones in 1996 (URL licensing application), 2001 (intermediary report) and 2005 (Dossier 2005 feasibility assessment). At each step the acquired geo-scientific information was used to refine the disposal design and then was transferred to the safety case. Our knowledge has been more and more growing; up scaling and simplification processes have been more and more important issues in qualitative and quantitative safety analyses. (author)

[en] The concept of underground disposal of toxic or radioactive materials is based on the idea that some geologic formations are capable to ensure the confinement of waste packages over very long periods of time by limiting the water influx towards the toxic elements and by fixing up those in solution. This paper presents the state-of-the-art about the researches on manufactured clays (nature, properties and conditioning) and about the researches on clay beds with the example of the Meuse/Haute-Marne (France) underground laboratory (geologic history, lithology, permeability, rock mechanics). (J.S.)

[en] The French Act published on the 28 of June 2006 has paved the way to siting of a repository in the transposition zone of the Meuse/Haute-Marne laboratory, so that the repository could be built and operational in 2025. Keeping in mind this long term objective, Andra has to prepare a licence application before 2015. The national plan for the management of radioactive materials and wastes (PNGMDR) provides intermediate key milestones to the development plan of the HLW and ILW geological repository project, which fit with our step-by-step approach. At the 2009 milestone, a limited area in view of detailed survey for the repository location has been proposed and a range of safety and reversibility related options for the design of the repository has been defined. The next 2012 milestone corresponds to the preparation of a public debate to be held in 2013. All the facilities of the repository have to be described in regard of surface location proposal(s) and their main impacts on the site environment identified. A first version of the scientific and technical bases of the future application will be presented. For the last milestone (Dec. 2014), Andra will issue an application for the licensing procedure, containing in particular a preliminary safety report. As a consequence, the research programme has to address the challenging issues and their connection with design, safety and reversibility for these milestones. While the safety analysis conducted reveals that the repository appears to be robust in all the configurations envisaged with respect to its safety functions, both CNE and safety authority evaluations focus on the necessity to provide more comprehensive and realistic modelling of the repository behaviour for both exploitation and post-closure periods and of the radionuclide migration (e.g. characterising transport properties of EDZ, determining the hydric transient taking into account the gas production within the repository). Such requirements, that frequently request research developments that are at the frontiers of actual science, imply a dedicated organization of the research program that has been set up by Andra in early 2007. A sustained program has been prepared in view of the 2012 report. It is divided into three thematic: (i) control of the basic phenomenological processes, (ii) process coupling in the repository and with its environment, (iii) data up-scaling, and it is supported by a thorough URL experimental programme. This programme is launched progressively with a view of confirming acquired data and reducing further the margins of uncertainty, as far as it can significantly support the robustness of safety and design options

[en] Site studies always involve understanding the flow paths and the solutes transport within the host rock. In the case of a granitic massif, the main natural flows are controlled by the great discontinuities connected with the contiguous fractures of smaller dimensions. The characteristics of the initial fracture pattern will be modified locally during the construction of underground works and, subsequently, during the storage of exothermic radioactive waste, even if it is stored in a section of the massif that features a low fracturing density. The present paper looks at ways of forecasting these mechanical changes and their repercussions on the local hydraulic pattern around the works. These modifications will not be the same and will not have the same importance for all the fractures in the massif. (authors). 5 figs., 14 refs

[en] The Full Scale Seal (FSS) Experiment is one of various experiments implemented by Andra, within the frame of the Cigeo (the French Deep Geological Repository) Project development, to demonstrate the technical construction feasibility and performance of seals to be constructed, at time of Repository components (shafts, ramps, drifts, disposal vaults) progressive closure. FSS is built inside a drift model fabricated on surface for the purpose. Prior to the scale 1:1 seal construction test, various design tasks are scheduled. They include the engineering work on the drift model to make it fit with the experimental needs, on the various work sequences anticipated for the swelling clay core emplacement and the concrete containment plugs construction, on the specialized handling tools (and installation equipment) manufactured and delivered for the purpose, and of course on the various swelling clay materials and low pH (below 11) concrete formulations developed for the application. The engineering of the 'seal-as-built' commissioning means (tools and methodology) must also be dealt with. The FSS construction experiment is a technological demonstrator, thus it is not focused on the phenomenological survey (and by consequence, on the performance and behaviour forecast). As such, no hydration (forced or natural) is planned. However, the FSS implementation (in particular via the construction and commissioning activities carried out) is a key milestone in view of comforting phenomenological extrapolation in time and scale. The FSS experiment also allows for qualifying the commissioning methods of a real sealing system in the Repository, as built, at time of industrial operations. (authors)

[en] An international consensus exists about the fact that a potential disposal site can be characterized and evaluated only if underground facilities are made available. As a support to the development of a disposal project, a research program in an underground laboratory allows to supply relevant information for the evaluation of the general feasibility of the proposed concept. These researches may be carried out in 'generic'-type labs as well, meaning that their geologic and geographic situation do not correspond to a future disposal site. Their aim is to study a particular type of rock (clay, salt, granite..). The later steps include the confirmation of the host rock qualities and the detailed design of the disposal facility. Content: 1 - Context of the underground laboratory researches in France; 2 - the underground laboratories in the framework of the 1991 law: projects, the Meuse/Haute Marne underground laboratory: objectives and design; construction; experiments carried out; contribution of the underground laboratory to the demonstration of the disposal feasibility; 3 - experimental program of the underground laboratory: role of the laboratory in the project development, 2008-2010 program, perspectives beyond 2010, role of the underground laboratory in the French research; 4 - programs of the underground laboratories in Europe: laboratories in granitic formations, laboratories in clayey formations. (J.S.)

[en] The feasibility study presented in the Dossier 2005 Argile set out to evaluate the conditions for building, operating and managing a reversible disposal facility. The research was directed at demonstrating a potential for confining long-lived radioactive waste in a deep clay formation by establishing the feasibility of the disposal principle. Results have been enough convincing and a Planning Act was passed on 28 June, 2006. Decision in principle has been taken to dispose of intermediate and high level long-lived radioactive waste in a geological repository. An application file for a license to construct a disposal facility is requested by end of 2014 and its commissioning is planned for 2025. Based on previous results as well as on recommendations made by various Dossier 2005 evaluators, a new scientific programme for 2006-2015 has been defined. It gives details of what will be covered over the 2006-2015 period. Particular emphasis is placed on consolidating scientific data, increasing understanding of certain mechanisms and using a scientific and technical integration approach. It aims at integrating scientific developments and engineering advances. The scientific work envisaged beyond 2006 has the benefit of a unique context, which is direct access to the geological medium over long timescales. It naturally extends the research carried out to date, and incorporates additional investigations of the geological medium, and the preparation of demonstration work especially through full-scale tests. Results will aim at improving the representation of repository evolutions over time, extract the relevant parameters for monitoring during the reversibility phases, reduce the parametric uncertainties and enhance the robustness of models for performance calculations and safety analyses. Structure and main orientation of the ongoing scientific programme are presented. (author)