miniRUEDI used for gas monitoring in a full-scale experiment targeted at underground radioactive waste disposal

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.

Highlights:

  • 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.