Evaluation of Used Fuel Disposition in Clay-Bearing Rock

Technical Report · Fri Sep 15 00:00:00 EDT 2017

DOI:https://doi.org/10.2172/1761958· OSTI ID:1761958

Jove-Colon, Carlos F. ^[1]; Wang, Yifeng ^[1]; Hadgu, Teklu ^[1]; Zheng, Liange ^[2]; Rutqvist, Jonny ^[2]; Xu, Hao ^[2]; Kim, Kunhwi ^[2]; Voltolini, Marco ^[2]; Cao, Xiaoyuan ^[2]; Fox, Patricia . ^[2]; Nico, Peter S. ^[2]; Caporuscio, Florie A. ^[3]; Norskog, Katherine E. ^[3]; Zavarin, Mavrik ^[4]; Wolery, Thomas J. ^[4]; Atkins-Duffin, Cindy ^[4]; Jerden, James ^[5]; Gattu, Vineeth Kumar ^[5]; Ebert, William ^[5]; Buck, Edgar C. ^[6] ; Wittman, Richard s. ^[5]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
4. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
5. Argonne National Lab. (ANL), Argonne, IL (United States)
6. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

The DOE R&D program under the Spent Fuel Waste Science Technology (SFWST) campaign has made key advances in experimental and modeling aspects of chemical and physical phenomena towards the long-term safety assessment of nuclear waste disposition in deep clay/shale/argillaceous rock. Experimental activities on clay barrier interactions with fluids and radionuclides provide the much needed knowledge to evaluate engineered barrier system (EBS) performance. Thermal-Hydrological-Mechanical-Chemical (THMC) model development of clay provides a rigorous simulation platform to assess the complex dynamic behavior of engineered and natural barrier materials in response to coupled process phenomena induced by heat-generating nuclear waste. This report describes the ongoing disposal R&D efforts on the advancement and refinement of coupled THMC process models, hydrothermal experiments and geochemical modeling of on barrier material (clay/metal) interactions, spent fuel and canister material degradation, radiolytic phenomena and UO₂ degradation, and thermodynamic database development. These play an important role to the evaluation of sacrificial zones as part of the EBS exposure to thermally-driven chemical and transport processes. Clay-zeolite phase equilibria play a key role in the mineralogical transformations of clay barrier conducive to loss in swelling properties but also in controlling H₂0 uptake/release through hydration/dehydration reactions. The result is volume changes can affect the interface / bulk phase porosities, transport, and the mechanical (stress) state of the bentonite barrier. Characterization studies on barrier samples (bentonite/cement) from controlled tests at underground research laboratories (URLs) provide key insights into barrier materials interactions at EBS interfaces. Spent fuel degradation modeling coupled with canister and cladding corrosion effects demonstrate the strong influence of H₂ generation on the source term.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE); USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000; NA0003525
• OSTI ID: 1761958
• Report Number(s): SAND-2017-10533R; SFWD-SFWST-2017-000006; 674069; TRN: US2214984
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
58 GEOSCIENCES