Groundwater in the Perthus Tunnel: feedback after excavation(Am03026)

This work introduces the experiences concerning water management, surface and groundwater impact observation wells, ground injections and water quality control of the 8,4 km long Perthus high speed railway tunnel. During excavation granodiorites, schists, diorites, gneiss, black schists and coarse fluvial deposits were encountered. Some important tectonic structures with associated groundwater flow have also been crossed. A study is then presented of the hydrothermal springs of Le Boulou, which have not been impacted.