Architecture and management of a geological repository - Andra

9 – Nuclear operating resources in the repositoryThe docking of C transfer casks isconducted at right angles to theshuttle's axis of motion. As in theprevious case, the transfer cask ispicked up by the shuttle afterbeing deposited by the transfervehicle. The shuttle travels in theaccess drift serving severaldisposal cells. After stopping atthe head of the cell, the transfercask is moved sideways and thendocked to the shielded trap doorof the cell (see Figure 9.2.9).The docking of spent fuelstransfer casks is conducted after arotation by a quarter turn, as thelength of the transfer cask doesnot allow it to be transported atright angles to the axis of thedrift, in contrast to the case of Cwastes.Figure 9.2.9 Docking of C casks by the shuttle at the head of the cellThe shuttle is equipped with a turning platform and a travel drive. Once the shuttle is positionedopposite a cell, the turning platform rotates the transfer cask through 90° and it is then movedsideways, to be docked in the cell shielded trap door.9.3 Process of installing the packages in the disposal cellsThe present section describes the equipment and procedures used for installing the packages in thedisposal cells [81]. The process can be reversed in order to retrieve the packages from disposal cells,if needed.The various technical solutions that could be used for each of the configurations studied (B wastes, Cwastes and spent fuels) are presented and compared. The choice of the preferred solution at this stageof the studies results from considerations of sturdiness, of minimising the height of the vehiclesentering the cells and of reducing the size of empty spaces after installing the packages.9.3.1 General principles of the installation of packages in disposal cellsThe design principles chosen for the procedure and the equipment for installing disposal packages incells have to fulfil two essential functions: the function of transferring the disposal package from theprotective transfer cask to its disposal position in the cell and the function of radiological protectionfor personnel.In the three configurations studied (B wastes, C wastes and spent fuels), the function of transferringthe packages requires that the transfer cask containing the disposal package be first docked at the headof the cell. A single type of machine then extracts the package and installs it in the cell.In the case of C wastes and of spent fuels, the geometrical configuration of the cell (a cylinder whosediameter is adjusted to the size of the disposal package) must allow this machine to be included in theshielded container of the transfer transfer cask. It consists of a robot connected to the transfer cask byan umbilical cable. It is brought back into the transfer cask after the installation of each package. For Cwastes, the system chosen is a self-propelled push robot with step-by-step type jacks. For spent fuelsthe system chosen is a transporter working on an air-cushion principle.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM344/495