Architecture and management of a geological repository - Andra

3 – High Level Long-Lived WasteScenario S2 takes the hypothesis that reprocessing of some of the UOX fuels will continue until 2010(8,000 tHM of UOX1 and 8,000 tHM of UOX2), but will cease after this date. Suspending therecycling of uranium and plutonium changes the overall distribution of the types of fuel removed fromthe reactors. Direct disposal of non-reprocessed fuels will then involve 29,000 tHM, including12,500 tHM of UOX2, 14,000 tHM of UOX3, 500 tHM of URE and 2,000 tHM of MOX.As stated in Chapter 2, the studies concern conditioned waste. Conditioning processes have thereforebeen defined for existing unconditioned waste as well for future waste. The hypotheses adopted takethe industrial processes currently implemented by the producers: vitrification, compaction,cementation and bituminisation.The scenarios considered also allow a robust approach for the repository study in light of possiblemanagement changes downstream of the cycle.In addition to these scenarios, the question of management of spent fuels from French reactors otherthan the EDF's pressurised water reactors (especially research and military reactors) was alsoconsidered. In all events, their reprocessing will only produce a marginal quantity of waste comparedwith the waste from reprocessing EDF fuels. For exploratory purposes, the possibility of directdisposal of these fuels was given special attention, without predicting the choices concerning theirmanagement.3.2 Description of the primary waste packagesAfter surveying the types of waste and defining their conditioning process, a large variety of primarypackage families emerge (61 in total). They differ from one another in their chemical and radiologicalcontent, heat rating and radiation level which depend on the presence of certain radionuclides, the typeand geometry of their package and their quantity.This section describes these various primary packages. In addition to making the basic distinctionbetween category B waste (intermediate-level long-lived waste generating little or no heat), category Cwaste (vitrified high-level waste) and spent fuels, the packages are grouped according to the similarityof the disposal problems they present.3.2.1 Primary B waste packagesThe survey of existing and forecast B waste reveals a wide diversity of types of waste, depending onits source and the processes that produced it.The following paragraphs provide a description of these types of waste and their actual or predictedconditioning processes. From here on, wastes have been grouped essentially on the basis of their typeand conditioning method, into the following seven sets: activated metal waste from nuclear reactors,bituminised liquid effluent treatment sludge, cemented or compacted technological waste, cemented orcompacted cladding waste, cladding and technological waste in drums, sources, and radium- andamericium-bearing waste.3.2.1.1 Activated metal waste from nuclear reactorsThe first set of B waste comes directly from electricity-generating reactors. This is operating wastefrom the existing pressurised water reactors (PWR) and activated waste from the SUPERPHENIX fastneutron reactor.PWR neutronic poison and control rod assemblies represent more than eighty percent of the totalweight of activated waste. Each assembly contains twenty-four fuel rods suspended from a supportsystem which fits into the locations left for this purpose in the fuel assemblies (see Figure 3.2.1).DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM76/495