Tome Architecture and management of a geological repository - Andra

5 – B waste repository zoneTable 5.7.1Repository components during the various repository phasesCOMPONENTPERIODMAIN REPOSITORYFUNCTIONSPROPERTIES HARNESSED1. GEOLOGICAL MEDIUM: GRANITEDuringoperationEmplacing (and being able toretrieve) the packages in thecellsMechanical strengthVery low permeabilityPart of the granite rockwhere a disposal cell isinstalledAfterclosureProtecting the disposal cellsfrom the circulation of waterDelaying and reducingradionuclides migration to theenvironmentChemical properties of the granitewater that tend to delay radionuclidemigration (reducing environment,etc.)Delaying and reducingradionuclides migration to theenvironmentLow permeability (at a distance fromthe significant water-conductingfractures)Granite "block" wherethe disposal module isinstalledAfterclosureProtecting also the disposalcells from water circulationLow underground hydraulicgradientsChemical properties of the granitewater that favour the delay ofradionuclide migration (reducingenvironment, etc.)Isolating the waste, protectingthe disposal cells from watercirculationUnderground installation of therepository (500 m taken asreference)Low permeability (at a distance fromthe major faults, the main vectors ofwater in the massif)The repository hostingpart of the granite massifAfterclosureProtecting also the disposalcells from the circulation ofwaterLow underground hydraulicgradientsDelaying and reducingradionuclides migration to theenvironmentChemical properties of the granitewater that tend to delay radionuclidemigration (reducing environment,etc.)Geo-dynamic context that ensuresfavourable repository conditions aremaintained in the long term,particularly erosion phenomenaDossier 2005 Granite - ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL REPOSITORY154/228