Fundamental understanding of radionuclide retention (FUTURE)
Quantification of long-term entrapment of key radionuclides in solid phases to inform reactive transport models and the influence of redox
This WP aims at realizing a step change in quantitative mechanistic understanding of radionuclide retention in the repository barrier system, the key mission of any repository for radioactive waste. In consequence, the raison d’être of this WP concerns the identification of constraints and the increase in predictability of RN migration properties in “real” clay and crystalline rocks, quantifying the influence of key parameters of the heterogeneous rock/water system such a rock structure, redox interfaces, water saturation, reversibility etc. with the goal to develop multicomponent mechanistic sorption models, fracture and/or pore scale simulations of radionuclides transport in both in crystalline clay rock considering the combined analysis of reactivity, structure, flow field, and RN mobility/retention.
“ Radionuclide mobility” has been identified by the mandated actors of WMO, TSO and RE as one of the key themes (4) of the EJP, the SRA and its concretization in the roadmap. It is a key theme in all radioactive waste management countries in Europe, a cornerstone for any proof of safety of nuclear waste disposal concepts. Hence, it was evident to all actors that this theme should also be part of the first EJP, acknowledging that there has been research on the various topics of radionuclide migration for more than 30 years, often funded by the European Commission, but realizing as well that various key themes have not been addressed in previous European projects (e.g. FUNMIG, SKIN, RECOSY) with sufficient depth and with sufficient potential for applicability on the real repository systems in clay or crystalline rock. The results of the project are expected to reduce uncertainties and over-conservatism of current approaches and improve the scientific basis, the realism and credibility for the safety case of deep geological disposal in clay and crystalline rock.
Major highlights (June - Nov 22) and forward look
The fourth year of the FUTURE project is focused on the finalization of the experimental activities, the analysis and interpretation of the results. The genuine highlight of the reporting year was the annual work package meeting which could be held in person for the first time after the kick-off meeting in 2019.
Thanks to the intensive laboratory work, experimental activities on the sorption and transport of radionuclide are providing increasing evidence that data on dispersed systems can be transferred to compacted state for the most of the element studied in the project (Se, Ra, Ni, Co, Eu, U, …). Reactive transport experiments and simulation in crystalline rocks have come with a consistent model for Ra retention and mobility. Many project partners working on redox active actinides have presented their results of the project ATAS-AnXAS Workshop.
Thanks to the increasing number of results coming from the experimental activities the interaction with modelling team in DONUT and KM-Workshop has intensified including training events for early carrier researchers. Interaction with end-users resulted in stronger interest of WMO, including ones not formally participating to the project since the beginning.