National assessment board for research and the studies into the management of radioactive waste and materials instituted by the law no.2006-739 of June 28, 2006 - Assessment report No. 5

The law provides that long-term management of long-lived, high-level waste comprises two aspects, which are not mutually exclusive: the partitioning and transmutation of the actinides present in spent fuel from nuclear reactors, and the geological disposal of long-lived high- and intermediate-level waste. This report is organised to reflect the two complementary aspects of R and D on the management of radioactive waste and materials: partitioning and transmutation (chapter 1), and the storage and disposal of LLHL and LLIL waste (chapter 2). In 2011 the Board decided to go into detail on the subject of the potential impact of transmutation of actinides on the disposal of the waste produced in the future, in a set of reactors suitable for multi-recycling. This question is dealt with in two chapters of the report. The Board continues to observe the overall international situation (chapter 3), and this year devoted an entire hearing to the different visions of the nuclear cycle held throughout the world. This hearing took place a few weeks before the accident in Fukushima. Contents: Chapter 1 - Partitioning and transmutation: scientific and technical context; transmutation and multi-recycling (Three important actinides potentially concerned by transmutation: Plutonium, Americium, Curium; Transmutation rate); demonstration tools; scenarios; ASTRID prototype (Core, Cooling and conversion, Designs and materials for Astrid); Reprocessing and fabrication of fuel (Experience and lessons learned; Pilot reprocessing facility for Astrid); transmutation in ADS; transmutation and disposal (Radiotoxicity of the inventory; Residual thermal power in LLHL waste); other scenarios; conclusion; Chapter 2 - disposal and storage: introduction; inventory; ZIRA (Contributions of the new 3D geophysics campaign; Knowledge of lithostratigraphic variations in the Callovo-Oxfordian layer; Knowledge of regional and local hydrogeology; Hydrogeological modelling situation); ZIIS - Integration of the structures in the surrounding land and the environment: Safety and security constraints; Environmental constraints; Reversibility constraints; Advantages and disadvantages of connecting the bottom to the surface via an inclined drift; moving towards the creation of a geological disposal site: the industrial centre for geological disposal (CIGEO): Brief analysis of the STI project; Design of the Cigeo project draft phase; Development of the Cigeo project; scientific work (Thermodynamics: Thermal disturbances; Thermal experimentation; Thermodynamics and transmutation; Conclusion); Geomechanics: Excavation-Damaged Zone (EDZ): safety issues; Tests conducted in the LLHL waste cavities; Sealing; Geomechanical modelling and conclusions; Underground laboratory experiments: Experiments in the Meuse/Haute-Marne underground laboratory; Experiments aimed at characterising the near field; Experiments aimed at characterising the far field); reversibility (Introduction; Circumstances that may lead to retrieval; Changes in the cavities and packages during the reversibility period; Reversibility and storage; Reversibility exercises; Conclusions); memory of the site; Chapter 3 - international overview: different options for managing LL, IL and HL waste; international legal context; research laboratories and underground disposal facilities; sources of fast irradiation; R and D on ADS; R and D on deep geological disposal (Performance levels of the disposal facility; Environmental impact of the disposal facility; Governance and participation of stakeholders); new technologies for partitioning and transmutation (R and D on partitioning and transmutation; Nuclear databases; Economic and geopolitical aspects); education, training and knowledge management; Appendices: members of the national assessment board - November 2011; bodies heard by CNE2; list of documents provided to the board