nuclear safety solutions
piles of graphite-column assemblies with generally hexagonal sections; those piles were surrounded by reflector columns ; sheaths consisting of cylindrical graphite shields laid out around the fuel element, pile of graphite blocks at Chinon EDF The GGR reactors are all out of service and their fuel elements have been unloaded.
However, pile-ups and reflectors are still present in the reactors, while the sheaths have already been stored at the different operators EDF, CEA or COGEMA, those elements contain carbon 14 and chlorine 36, for example, the latter produced by the activation of impurities.
Andra is therefore seeking, in co-operation with EDF and the CEA, to develop a specific system adapted to that type of waste, both waste categories are slightly radioactive but contain, long-lived radioelements.
The french National Radiactive Waste Management Agency is responsible for the long-term management of all radioactive watse in France and for the conduct of investigations on its disposal in deep geological formation.
The concept that is currently being contemplated for both is a subsurface repository excavated in a clay formation at a sufficient depth approximately 15 m to secure consistently the waste away from human beings, line 1.
nuclear safety solutions
Partitioning and transmutation studies, the fission of a nucleus broken into two new nuclei by the impact of a neutron is a form of transmutation.
Studies in this area are generally aimed at finding solutions to partition and transmute radioactive elements contained in waste, this means using nuclear reactors, particle accelerators or innovative system to transform long-lived radioactive waste into stable or short-lived isotopes and thus reduce the volume of waste requiring confinement over very long periods of time.
Line 2, deep geological disposal studies, the aim is to provide the necessary data for assessing the feasibility of a deep geological waste repository.
This means comparing theoretical repository concepts with the particular conditions encountered in clearly defined geological sites, and demonstrating their safety over the very long term, the repository concepts studied are based on the multiple-barrier principle.
Andra, National Radioactive Waste Management Agency
radioactive storage waste
radioactive storage wastes
The barriers are, the waste package the waste and the material used to stabilise it in a suitable overpack, the engineered barrier inserted between the waste package and the rock, and the geological barrier, i..
The actual rock, site characteristics are first studied from the surface, then in situ in an underground research laboratory.
Virtual image of a drift in the Underground Research Laboratory, in 1999, the French government approved the decision to create a laboratory on a clay site in Bure Meuse/Haute-Marne.
Andra is in charge of this programme, line 3, studies on conditioning and long-term near-surface storage.
Research in this field includes the development of devices to store waste over several decades under acceptable safety conditions, this work is conducted by the CEA, with assistance from Andra and the CNRS, and is based on information provided by EDF and COGEMA, the chief producers of high-level and long-lived intermediate-level radioactive waste.
Drum containing vitrified waste, as part of its research into the feasibility of a deep geological waste repository, Andra is conducting a programme to acquire date on the clay medium.
