Architecture and management of a geological repository - Andra

10.3.9 Observation of spent fuel disposal cellsThis section describes the observation equipment which could be envisaged in the spent fuel controlcells, if necessary. This equipment is similar to that described for C cells. The spent fuel cell differfrom C waste cells in that they contain two additional components: the buffer and the metal lining ofthe cell. Accessibility during the construction phase allows instrumentation of the near-field throughthe perforated lining. Finally, it is possible to install the sensors in the prefabricated buffer rings beforethey are put in place.The distribution of the instrumented section is comparable to that described for the C cells. Aninstrumented section of a control spent fuel cell (cf. Figure 10.3.18) is made up of three monitoringunits, incorporating the monitoring of the sleeve, the buffer, the lining, and the rock.Figure 10.3.18Instrumented section of a spent fuel cellThe sensors put in place on the extrados of the sleeve and on the intrados of the lining are identical tothose described in section 10.3.8.1 (cf. Figure 10.3.15). The monitoring units in the swelling claybuffer are identical to those proposed for the clay core of B cell seals or C cell plugs. Also, aninterstitial pressure cell is embedded in a radial bore-hole in the host rock.Therefore, the monitoring equipment makes it possible to monitor thermal and mechanical evolutionsof the structure and the hydraulic evolutions of the near-field. Their combination makes it possible toidentify any thermomechanical effects.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM413/495