Architecture and management of a geological repository - Andra

5 – Repository Modules• Airlock at cell head and radiological protectionFor the radiological protection of personnel, the cell head is fitted with an airlock separating theentrance drift from the cell body.• Cell access drift and sealThe cell access drift linking the cell and the connecting infrastructure, is designed to accommodate theseal for closing the cell. To help achieve the best performance from the seal, this drift has a usefuldiameter reduced to 5 or 6 m, according to the size of the packages to be disposed of in the cell, and itssupport and lining are designed specifically so as to limit any mechanical disturbances at the seal, as inthe case of the seals in connecting drifts. The length of this entrance drift (some fifty metres) isdetermined by the space needed for forming the seal and its retaining plugs.• Cell arrangementIn order to improve the compactness of the repository and simplify operation, grouping together somereference packages (in particular those small in number) can avoid the construction of several shortlengthcells and thus reduce the overall space requirement of the disposal area. However, to preventchemical interactions between packages capable of damaging retention properties in and around thecells, packages containing organic matter are disposed of separately in other packages [37].• Cell ventilationThe filler concrete includes longitudinal ventilation ducts for ventilating the cell throughout itsoperation until it is sealed. This facility meets the need to control gases. This ventilation also helpsreduce the temperature in the initial years of package disposal.• Summary of requirements and adopted solutionsThe contribution of the various cell components to the functions of disposal is summarized in Table5.1.1. [7], [22].DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM168/495