"Assessment of barrier integrity in geological repositories for nuclear waste disposal and contaminant isolation":

Barrier integrity is a crucial aspect for the assessment of subsurface technologies. For the storage of thermal energy and other energy carriers, or the deposition of high-level nuclear or chemotoxic waste, different repository concepts in diverse geological candidate formations such as rock salt, clay stone and crystalline rock are being discussed. Computational methods and numerical simulations, in conjunction with experimental studies across scales from micro-scale to field scale, are an integral part of safety and environmental-impact assessment concepts involving barrier integrity as a key component. Reliable comparative analyses of potential technological options require coupled physical (thermo-hydro-mechanical chemical) models capturing the individual particularities of each rock type and associated geotechnical repository and barrier concept to a comparable level of sophistication. Structural as well as process complexity and large computational domains combine to render a reliable and efficient analysis a major challenge. This complexity is often met by data scarcity and variability, necessitating the theoretical and computational treatment of uncertainties and variability at different scales involved in numerical analyses at different levels.

This session provides a platform for the exchange of geophysical, geochemical, geotechnical knowledge for assessing the integrity of barriers and multi-barrier systems considering equally conceptual, theoretical, computational and experimental aspects.

"Towards a safe nuclear waste repository – geoscientific, technological, social and regulatory challenges and approaches":

The successful implementation of safe, deep geological disposal of spent fuel, high-level waste and other long-lived radioactive waste is one of the currently most pressing and important environmental challenges in several countries in Europe and worldwide. Site exploration and assessment are primarily geoscientific tasks that require interdisciplinary collaboration of different geoscientific disciplines, like geophysics, geochemistry, mineralogy, geomechanics, and geological as well as THMC modelling. Successful and socially accepted site selection and implementation, however, not only depend on geoscientific state-of-the-art results and R&D programs but to a large extend on targeted, adequate and well-designed public outreach and public involvement/participation activities as well as on suitable regulatory frameworks. Both, geoscientific and technological as well as social and regulatory aspects complement each other and need to be addressed.
This session therefore welcomes contributions from research organizations, NGOs, waste management organizations, and regulatory bodies. Topics may include, but are not limited to, advances in exploration and modelling tools and approaches, safety assessment strategies, disposal concepts, national and transnational public outreach and public involvement programs, national regulatory frameworks. Preference will be given to contributions that highlight the interdisciplinary and especially transdisciplinary character of deep geological disposal research