Architecture and management of a geological repository - Andra

7 – The shafts and the driftsFigure 7.3.2Section of the package transfer shaftThe shaft’s special equipment is detailed in chapter 9. The shaft machinery can transport a payload of110 tons at a rate of 1 m/s. The cage weight is balanced by a counter-weight. The cage is guided bysteel profile guiding systems. A small independent emergency cage ensures the safety of the personnelassigned to the maintenance operations.7.3.2 Air exhaust shaftThe purpose of the air exhaust shaft is to ensure the general air exhaust from the repository(construction and operation), the evacuation of smoke in case of fire and, if neessary, the return ofpossibly contaminated air in case of an accident (air coming from the package transfer shaft).The need for a dedicated air exhaust shaft can be explained by the very high air flow rates (severalhundred cubic metres per second) and by the necessity of avoiding the placing of large-scaleequipment in stale air (diesel fumes, dust, other possible fumes) to the detriment of their resistanceover time.The shaft diameter is determined by ventilation requirements. The usable diameter is 10 m. It wouldallow a possible increase in ventilation capacity and limit energy expenses related to ventilation. Thestructure is divided into 3 compartments, one for each air exhaust. It is only equipped with equipmentfor inspections and maintenance.7.3.3 Personnel transfer shaft and construction shaftThis set of two shafts ensures the transfer of the other flows necessary for the construction, operationand closing of the repository. These shafts are also used for the entry of air for all the undergroundinstallations except for the package transfer shaft.In the architecture presented, one shaft is exclusively reserved for the transport of personnel and smallequipment. The other shaft, the construction shaft, ensures the extraction of broken rocks, the loweringof backfills in bulk, the descent of a surface-prepared concrete, the transfer of large-scale equipment,parts and building materials.The construction shaft can also serve as an emergency exit in case the personnel transfer shaft isunavailable.The equipment of these shafts is conventional equipment such as used in the mining industry. Cablesand pipelines are also installed in these shafts.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM295/495