Safeguards for the Design of Future Fast Neutron Reactors and Associated Fuel Cycle

Incorporating the need of safeguards at an early stage of a reactor design is way to increase the effectiveness and the efficiency of safeguard measures minimizing the possibilities of misuse of a power plant or nuclear material diversion possibilities. It is also obvious that the early introduction of safeguard requirements could reduce the impact of safeguard measures on the construction and operation cost of the facility. The design of a new reactor will integrate at the preliminary design phase confinement, containment, surveillance features, non-destructive assay equipment and their integration. Taking into account these requirements will also, as for safety, help the operator of the future nuclear plant in the agreement of the plant at the design phase by national and international authorities which are in charge of the Nuclear Material accounting and the safeguard application verification. A large amount of work has been made recently by the GEN IV forum to define and to assess the proliferation resistance of GEN IV reactors. Recently, the IAEA has developed a set of guidelines on “safeguard by design” describing the main reference requirements for the design of future nuclear facilities. Based on these studies and requirements, this communication will detail implementation of safeguard in the design of a sodium cooled fast neutron reactor (SFR). Main specificities of this reactor are the use of MOX fuel with high concentration of plutonium and the potential capacity of breeding. These two features require a greater attention in order to avoid any diversion of nuclear material contained in fresh or irradiated fuels. Scenarii of reactor misuse will also be analyzed to define the safeguard approach of the reactor. The identification of diversion pathways and requirements for nuclear material accountancy, will lead to a reasonable approach of safeguards specific to a sodium cooled fast reactor which will be describe as for instance the definition of Material Balance Areas (MBA) and some key measurement points (KMP). Specific instrumentation assay helping in the identification, characterization of fuel elements and the inventory of nuclear material will also be described. The safeguard for the reprocessing unit will require the development of material monitoring and implementation of measures at different strategic locations in order to provide near real-time information on the quantities and distribution of nuclear materials in the process.