2009 Report to Government on National Research and

Box 6. Examples of Topics on which Underground R&D is needed for GDF
Design and Safety Case Development
• The responses of the rock mass and existing underground openings <strong>to</strong>
excavation, this could include:
• excavation techniques and excavation support techniques for the long term
• deep drilling techniques
• research in<strong>to</strong> the response of rock masses <strong>to</strong> excavation technique, and
opening size and orientation;
• the development of EDZs
• the possible effect of excavation on existing underground openings in given
in situ stress conditions and the influence of excavation on stress fields.
• Engineered barrier performance:
• full scale barrier tests
• container tests
• buffer and overpack tests
• tunnel and shaft seals and ultimately facility seals
• borehole sealing
• Radionuclide movement through the geosphere:
• solute advection and diffusion
• colloidal transport
• radionuclide sorption
• gas threshold pressure relationships
• Waste handling under realistic conditions:
• effects of heat and radiation on the host rock
• heat effect on structures
• thermal-hydraulic-chemical-mechanical testing
• The long-term performance of the GDF and the efficacy of the EBS under
realistic conditions:
• demonstration and testing of disposal concept
• materials interfaces, for example surrounding the co-location concept
• backfill behaviour and efficacy
• corrosion of waste containers
• degradation of waste forms
• long-term performance of multiple underground openings.
5.39 The RWMD R&D Strategy explains how its R&D will evolve during the MRWS
process (NDA, <strong>2009</strong>b). It states that during Stage 5 (surface-based
investigations) its R&D will focus on the site-specific processes that will
determine the performance of engineered barriers or control the movement of
fluids and radionuclides. For Stage 6 it states that:
“A key aspect of this phase will be underground investigations. There will be
some site-specific information at a large spatial scale, which can only be
obtained by investigation underground in the specific geology <strong>to</strong> be
considered for hosting the facility. We will carry out these investigations as
part of the construction of the facility and therefore our planning does not
include a separate phase for R&D in an underground research labora<strong>to</strong>ry.”
CoRWM Document 2543, Oc<strong>to</strong>ber <strong>2009</strong> Page 86 of 151