Building confidence in models for complex barrier systems for radionuclides

• 成果类型: Article
• 署名作者: Sarsenbayev, Dauren; Tournassat, Christophe; Steefel, Carl I.; Wainwright, Haruko M.
• 署名单位: Massachusetts Institute of Technology (MIT); United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; Centre National de la Recherche Scientifique (CNRS); CNRS - National Institute for Earth Sciences & Astronomy (INSU); Universite de Orleans; Bureau de Recherches Geologiques et Minieres (BRGM); Massachusetts Institute of Technology (MIT)
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11705
• DOI: 10.1073/pnas.2511885122
• 发表日期: 2025-07-08
• 关键词: transport

摘要

The modeling and simulation of the Cement-clay Interaction-Diffusion field (CI-D) experiment at the Mont Terri site in Switzerland presented here demonstrates that it is possible to capture the multiscale physical and chemical features of natural and engineered barrier systems for radionuclides. The simulations are successfully carried out with the newly developed CrunchODiTi high-performance computing software that accounts for multiple continua, including a continuum representing the electrical double layer (EDL) developed along negatively charged clay particles in clay rock. The simulation also accounts for both the complex three-dimensional (3D) geometry, expected as the norm in a geological waste repository, and the anisotropy of the geological formation. In addition, the high resolution of the model makes it possible to include skin effects developed at the interface between highly reactive materials, in this case between the high pH cement and the circumneutral but electrostatic Opalinus Clay. The successful history matching with the field experiment demonstrates that the distinct geochemical and physical properties of the cement and the Opalinus Clay in the CI-D experiment can be accounted for. Such analyses are essential for developing a defensible safety case for the underground storage of radioactive waste.