European Joint Programme (EJP) – EURAD
Country / Region: Europe
Begin of project: July 1, 2019
End of project: June 30, 2024
Status of project: March 15, 2023
Gas injection tests (Popp et al. 2007): Experimental set up, finite element mesh and modelling results
Source: BGR
When radioactive waste is disposed of in deep geological formations, various thermo-hydraulic-mechanically coupled processes and their interactions have to be considered. Due to the corrosion of deposited materials and other processes such as radiolysis of the formation water, hydrogen gas is released. Driven by over-pressurisation and its lower density (compared to water), the gas can subsequently migrate through geotechnical and geological barriers. Additionally, high-level radioactive waste generates heat, which can lead to the alteration of clay minerals in the host rock and in the geotechnical barrier, especially if the temperature rises to levels greater than 100 °C. Micro-cracks and fractures induced by these processes can contribute to a long-term change of the chemical and hydraulic properties with potentially unfavourable impacts on the barrier integrity. In order to improve our understanding of gas migration and temperature-driven processes, the EJP-EURAD project brings together more than 50 institutions involved in radioactive waste disposal from all of Europe: Among the participants, there are waste management organisations (WMOs), technical support organisations (TSOs) and research entities (REs). The French WMO ANDRA (Agence nationale pour la gestion des déchets radioactifs) is responsible for the coordination and management within the EJP-EURAD project.
The EJP-EURAD project comprises various work packages (WPs) with regard to different physical processes, two of which with participation of the BGR:
1) WP HITEC: The objective of the WP is an improved understanding of
a. the impact of high temperatures on geotechnical and mineralogical properties of both bentonites and argillaceous rocks,
b. governing processes in order to validate existing numerical THMC-coupled models at high temperatures,
c. the impact of elevated temperatures on the transport of gas and aqueous solutes.
2) WP GAS: The objective of the WP is an improved understanding of
a. gas migration processes in argillaceous rocks and bentonites,
b. the impact of gas migration on the integrity of the geological and geotechnical barriers,
c. gas migration processes on the scale of deep radioactive waste repositories.
In order to accomplish these research objectives, the EJP-EURAD project relies on close collaboration of the partners from different European nations. Furthermore, a special focus of the project is the close coordination of experimental scientists and numerical modelling groups. This ensures that both experiments and the numerical modelling of processes contribute in an optimum way to the scientific progress. Progress updates and results of ongoing research are regularly published on the project homepage.
Within the ‘German Cluster’, the BGR works in close collaboration and coordination with the UFZ (Helmholtz-Zentrum für Umweltforschung, Leipzig) and the BGE Technology GmbH (a subsidiary of the Bundesgesellschaft für Endlagerung mbH, Peine). The activities of the BGR within the EJP-EURAD project are coordinated by the KIT (Karlsruhe Institute of Technology).
The EJP-EURAD project is supported by the European Grant Agreement No. 847593.
References:
Xu, W.J., Shao, H., Hesser, J., Kolditz, O., (2014): Numerical modelling of moisture controlled laboratory swelling/shrinkage experiments on argillaceous rocks. Geological Society, London, Special Publications 400 , 359 - 366 (http://dx.doi.org/10.1144/SP400.29)
Project contributions:
