Architecture and management of a geological repository - Andra

3 – High Level Long-Lived WasteA second package sub-assembly contains fuel cladding waste. The waste is temporarily conditioned instainless steel drums known as EIP drums (from the French acronym for multi-purpose storagefacility). The packages hold aluminium and stainless steel cladding waste or magnesium-alloycladding waste. They weigh less than 300 kilograms on average (excluding waste immobilisationmaterial). Packages containing aluminium and steel cladding waste have a heat rating in the order of10 watts, mainly attributable to cobalt-60; this will be 0.5 watts at most by 2025. The packageirradiation level is 25 Sv/h, becoming 2 Sv/h by 2025.The packages containing the magnesium alloy cladding waste do not transfer heat. Their irradiationlevel, attributable to two isotopes, barium-137m ( 137m Ba) and europium-154 ( 154 Eu), is 3 Sv/h,becoming around 2 Sv/h by 2025.A third package sub-assembly contains technological waste made up of a mixture of metallic materialsand organic matter or metallic materials alone. The temporary conditioning method is also to place thewaste in EIP drums.The packages containing metallic and organic waste weigh 90 kilograms on average (excluding wasteimmobilisation material). They do not transfer heat and are not irradiating. Hydrogen release fromradiolysis of the organic matter should be taken into account.The packages containing the metallic technological waste do not transfer heat nor produce gas. Theirirradiation level is around 0.05 Sv/h, becoming around 0.02 Sv/h by 2025. The finished packagesweigh 240 kilograms on average, excluding waste immobilisation material.Table 3.2.3 summarises the principal characteristics of the three sub-assemblies of the cladding andtechnological waste packages.Table 3.2.3Summary of the characteristics of the cladding and technological waste placedin drumsPackage subassemblyOverallpackagevolume (m 3 )Presence ofmetallicwastePresence oforganicwasteProduction ofgas byradiolysis(H 2 )Thermicity, irradiationlevel when packagesproduced1 0.175 x None None Packages do not transferheat, only slightly irradiating2 0.428 x None None Nil or average thermicity,average or high irradiationlevel depending on packages3 0.428 x x x Packages do not transferheat and are not irradiating3.2.1.6 SourcesThis waste groups PWR source rods and sealed sources for industrial use.Source rods are operating waste from PWR reactors, similar to the variety of active metallic wastedescribed in Section 3.2.1.1. Forming part of the rods contained in the primary and secondary sourceclusters, they are used to raise the flow level to a threshold that may be detected by neutron countersduring reactor start-up. Primary source rods containing a californium capsule are unloaded at the endof the first cycle, whilst secondary source rods, made up of an antimony-beryllium mixture, gothrough several irradiation cycles before being scrapped. The primary source clusters unloaded from900 MW reactors are reprocessed to recover the californium capsules and are therefore not consideredwaste (and are therefore not included in the inventory). The total weight of waste for conditioning isless than two tonnes.The conditioning hypothesis retained for the study is, like for the other PWR activated waste, shearingthen compacting of the source rods before being placed in a CSD-C container. Note that the source rodconditioning will produce a maximum of four CSD-C.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM89/495