Grimsel Training Centre: Engineered Barrier System (EBS) / Bentonite Course 2020

Nagra offers a 5-day workshop at the Grimsel Test Site covering the various aspects related to Engineered Barrier Systems (EBS) and specifically bentonite.  Participants will get an introduction to engineered barrier / bentonite requirements, properties and applications in radioactive waste topics. Some lectures will especially focus on gases in an EBS.

International and national experts will provide keynote lectures and experience, discussion forums will allow the exchange of knowledge and current research strategies. GTS lab visits will provide first hand insights of ongoing experiments and will support the discussion of related topics in the course.

The course aims to impart both theoretical and practical knowledge and experience. The course shall help participants in defining, managing, planning, tendering and carrying out their own field (URL) and lab experiments at various scales and how to interpret data and results with respect to their safety case.  The covered topics will be transferable to various field investigations and implementers RD&D requirements.

Daily activities will be organized in alternating lecture blocks and visits to experiments at the Grimsel Test Site.  Additionally, a laboratory visit to one of our collaborating universities (ETH Zürich, University of Bern) will be organized.

The main topics of the bentonite training course are:

• Safety requirements
  • General introduction to radioactive waste disposal concepts and requirements and the role of the host rock and engineered barrier systems
• Clays and Bentonites as engineered barriers
  • Properties (chemical, physical, thermo-hydro-mechanical); Bentonite origin, types and properties
  • THM/THC behaviour; Interactions with cements, metals, host-rocks and gasses
  • Bentonites/clays and Bentonite production and quality
• Modelling bentonite behaviour
  • Approaches and computer codes; Validation with field data
• Experiments
  • Scale issues (lab – mock-up – field scale); Safety requirements and large-scale experiments (demonstration vs processes understanding)
  • Designing and constructing experiments; Monitoring and excavating experiments;
  • Management of experiments
• Onsite visit and discussion of GTS Experiments (and others)
  • Under construction: HotBENT (high temperature buffers)
  • Running: CIM (Carbon Iodine Migration), CFM (Colloid Formation & Migration), GAST (GAs permeable Seal Test), MACOTE (MAterial COrrosion TEst),
  • Completed: FEBEX (Full Scale Engineered Barrier EXperiment)

Further details are available in the course flyer and on the Grimsel website.