Architecture and management of a geological repository - Andra

6 – Overall underground architectureZone BZone C01 800 000 m 3 100 000 m 3Communs1 900 000 m 3Zone C3 800 000 m 3Figure 6.6.2Breakdown of the excavated volumes in the scenario S1aApproximately 40 % of the excavated rock may be reused for the backfilling of the drifts. Thedifference compared to 100 % is based on the volumes occupied by the disposal packages and thestructure liners and by the backfill “swell factor” effect 114 .The volumes of excavated and backfilled materials can be compared to the volumes excavated in largesedimentary underground mines of coal, potash, bauxite or iron. These volumes can represent severaltens of millions of cubic metres exploited over several decades.6.6.3 Adaptation of the architecture to the scenarios S1b, S1c, S2The architecture presented above can be adapted to the other scenarios considered in the study (seechapter 3). Figure 6.6.3 shows the adaptation of the architecture to the scenarios S1a, S1b and S2. Itshould be noted that the scenarios S1b and S1c lead to very similar architecture plans 115 .114 A backfill made up of crushed and compacted rock has a density less than the density of the rock in place115 In fact, if the number of C waste packages is less in the S1b scenario, then the considered packages are more exothermal and imply alower storage density.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM283/495