In their recent paper “On-line monitoring of the gas composition in the full-scale emplacement experiment at Mont Terri (Switzerland)“, Yama Tomonaga and his colleagues at Nagra, Eawag and ETH Zurich used a miniRUEDI to study the dynamics and the fate of the gas species in a tunnel of a full-scale experiment targeted at radioactive waste disposal in Switzerland.
- An on-line gas monitoring has been implemented for the FE experiment at Mont Terri underground rock laboratory.
- The monitoring of gas species was performed successfully over several months.
- Rapid gas exchange occurs between drift backfilling and FE niche/host rock.
- Terrigenic gases (e.g., 4He, 40Ar, CH4, CO2) accumulated in the backfill pore space.
- Fast gas exchange partly explains the O2 removal from the backfill pore space.