Architecture and management of a geological repository - Andra

3 – High Level Long-Lived Waste3.2.2.2 Vitrified waste packages from current productions or those planned in the shorttermThese packages contain solutions of fission products produced by reprocessing PWR UOX/enrichedrecycled uranium fuels in the COGEMA La Hague plants, conditioned as glass in a so-called CSD-Vstainless steel container (see Figure 3.2.17). It is assumed that production and conditioning of thewaste will occur after an average fuel storage time of eight years, after unloading from the reactors.The conditioned waste weighs 400 kilograms on average per package.A first group of waste packages relates to current industrial productions from a heat transfer viewpoint.Following the hypotheses adopted, the vitrified waste is made up of a mixture of solutions of fissionproducts from UOX1 (average combusion rate of 33 GWj/t), UOX2/enriched recycled uranium(average combustion rate 45 GWj/t) and UOX3 (average combustion rate 55 GWj/t) fuels.A second group of waste packages relates to packages with a slightly-increased heat rating. Thevitrified waste is made up of a mixture of solutions of fission products from UOX2/enriched recycleduranium and UOX3 fuels, with, as previously, average combustion rates of 45 GWj/t and 55 GWj/trespectively.The heat ratings of these packages are illustrated in Figure 3.2.15 (blue and red curves). They raise thequestion of storage time before being placed in a repository and of repository module design, to limitthe temperature to acceptable levels (see Chapter 2); this issue is dealt with in Chapter 5.The equivalent β-γ dose rate in pseudo-contact (5 cm) with the packages is about 240 Sv/h, after asixty-year cooling period.3.2.2.3 Future hypothetical wastepackagesThese waste packages relate to potential glass productions on the COGEMA La Hague site. Thesepackages have been defined in the scenarios adopted for the study on the assumption that productionand conditioning of the waste will take place, as for the previous glasses, after an average fuel storageperiod of eight years, after unloading from the reactors. Note that other possibilities could beenvisaged.Here also, the conditioned waste weighs 400 kilograms on average per package. The containers aresimilar to the ones presented above (CSD-V).A first waste packages describes glasses produced by conditioning solutions of fission products fromUOX and MOX fuels. Their make-up is defined as a mixture of 15% MOX and 85% UOX2.A second waste packages describes vitrified waste from reprocessing UOX fuels, which contains asmall additional plutonium load. The plutonium incorporation rate in the glass is fixed specifically atone percent, about 4 kilograms per package. The incorporated plutonium comes from the UOX2 fuels.The heat ratings produced by these packages are illustrated above in Figure 3.2.15 (green and orangecurves).The equivalent β-γ dose rates in pseudo-contact (5 cm) with the packages will be 235 Sv/h for theUOX/MOX glasses and 265 Sv/h for the glasses with plutonium respectively, after a sixty-yearcooling period.3.2.3 Spent fuelSpent fuels taken into account stem from the PWR reactors, as well as from halted plants and researchreactors (NUGG, EL4) and fuels produced by national defence activities. Remember that these aretaken into account in the study in the event they were to be considered as waste, assuming a halt inreprocessing; which is not current strategy in France.Under scenario S2, the fuel typologies considered (see Section 3.1) are: UOX2 and enriched recycleduranium (45 GWj/t), UOX3 (55 GWj/t) and MOX (48 GWj/t).DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM94/495