Nagra TBO
Hydraulic tests in deep boreholes, complete hydraulic characterisation of the subsurface
A sound knowledge of the hydrogeological conditions in the subsurface is of great importance for the safety of a deep geological repository, and is an important criterion when comparing possible sites for a deep geological repository. The hydraulic tests in the deep boreholes were used to investigate the hydrogeology of the subsurface of the siting areas in detail, thus significantly completing the overall geological picture.
Solexperts carried out the hydraulic tests in the deep boreholes over a period of three years from 2019 to 2021. The focus was on the Opalinus Clay, which is to be investigated in more detail as the host rock for the deep repository for radioactive waste. Using our HDDP (Heavy Duty Double Packer) system, which we developed and produced ourselves, borehole sections were isolated and examined for their geohydraulic properties. Pulse tests, slug tests and pumping tests were carried out and evaluated analytically and numerically with the help of our subcontractor AFRY.
Key data
Number of deep boreholes: 5
Of which deviated boreholes: 1
Project duration: 2019 - 2021
Project volume: several million CHF
Client: Nagra
Project partner
Gas tests
In a deep repository, gas is produced over time by various processes, e.g. corrosion of steel. An important goal of the investigation campaign was to determine the in-stu gas entry pressure into the Opalinus Clay layers at the different sites. Solexperts modified their test equipment accordingly so that successful gas tests could be carried out.
Deflected well
The over 1000 m deep deviated borehole in Rheinau was also a technical challenge. With a large amount of material and the appropriate modifications to the test equipment, hydraulic tests and gas tests could be successfully performed.
Downloads
Hydrogeology
Hydrogeology
- Dilatometer, Lastplatten A.Thut 1977
- SysMoG® : Gas monitoring system
- Hydro-Solexperts
- Hydrologic Investigation using the Pump-Down-Packer System
- Hydrogeological and geotechnical in-situ testing for large caverns, M.Kech and D. Naterop, 2010
- DESTRESS_Peter Meier
- Armand, Piedevache PERMEABILITY MEASUREMENTS IN THE EXCAVATION DAMAGED ZONE
- Self-sealing experiments and gas injection tests in a backfilled microtunnel of the Mont Terri URL
- Interpretation of Core Extrusion Measurements When Tunnelling Through Squeezing Ground
- Innovative TDR applications for nuclear waste disposal sites
- A New Method for Real-Time Monitoring of Grout Spread through Fractured Rocks
- Specialized instrumentation for hydromechanical measurements in deep argillaceous rock
- Instrumentation for a gas path through host rock and along sealing experiment
- The Grimsel Migration Experiment: field injection–withdrawal experiments in fractured rock with sorbing tracers
- SurfMoG®H2 Gas monitoring probe for shallow H2-measurements
- Multi-Disciplinary Monitoring Networks for Mesoscale Underground Experiments: Advances in the Bedretto Reservoir Project
- In-situ leaflet
- Gas monitoring systems
- References HDDP
Rock laboratory systems
- Custom Packer System
- Innovative TDR applications for nuclear waste disposal sites
- 25 years of cross-fertilization between HADES and Mont Terri rock laboratory
Hydraulic Borehole Tests
- Dilatometer tests
- Hydraulic Tests
- HDDP – Heavy-Duty Doppelpacker-System
- HUGO TM – Auswertesoftware
- Pump-multi-packer-system
- Pump-Down Packer Systeme (PDPS)
