The natural barrier system (NBS) is an integral part of a geologic nuclear waste repository. The report describes progress in development of an integrated modeling framework that can be used for systematically analyzing the performance of a natural barrier system and identifying key factors that control the performance. This framework is designed as an integrated tool for prioritization and programmatic decisions.
This report summarizes research activities on engineered barrier system (EBS) model integration with the generic disposal system model (GDSM), and used fuel degradation and radionuclide mobilization (RM) in support of the EBS evaluation and tool development within the UFD campaign.
This roadmap is intended to advance deep borehole disposal (DBD) from its current conceptual status to potential future deployment as a disposal system for spent nuclear fuel (SNF) and high-level waste (HLW). The objectives of the DBD RD&D roadmap include providing the technical basis for fielding a DBD demonstration project, defining the scientific research activities associated with site characterization and postclosure safety, and defining the engineering demonstration activities associated with deep borehole drilling, completion, and surrogate waste canister emplacement.
Clay/shale has been considered as potential host rock for geological disposal of high-level radioactive waste throughout the world. Coupled thermal, hydrological, mechanical, and chemical (THMC) processes have a significant impact on the long-term safety of a clay repository. This report documents results from three R&D activities: (1) implementation and validation of constitutive relationships, (2) development of a discrete fracture network (DFN) model for investigating coupled processes in the excavation damaged zone, and (3) development of a THM model for the Full-Scale Emplacement Experiment tests at Mont Terri, Switzerland, for the purpose of model validation. One major goal is to provide a better understanding of the evolution of the excavation damage zone in clay repositories.
While both wet and dry storage have been shown to be safe options for storing UNF, the focus of the program is on dry storage of commercial UNF at reactor or centralized locations. This report focuses on the knowledge gaps concerning extended storage identified in numerous domestic and international investigations and provides the UFDC’s gap description, any alternate gap descriptions, the rankings by the various organizations, evaluation of the priority assignment, and UFDC-recommended action based on the comparison.
Development and implementation of future advanced fuel cycles including those that recycle fuel materials, use advanced fuels different from current fuels, or partition and transmute actinide radionuclides, will impact the waste management system. The UFD Campaign can reasonably conclude that advanced fuel cycles, in combination with partitioning and transmutation, which remove actinides, will not materially alter the performance, the spread in dose results around the mean, the modeling effort to include significant features, events, and processes (FEPs) in the performance assessment, or the characterization of uncertainty associated with a geologic disposal system in the regulatory environment of the US.
The United States (U.S.) currently utilizes a once-through fuel cycle where used nuclear fuel is stored onsite in either wet pools or in dry storage systems with ultimate disposal envisioned in a deep mined geologic repository. This report provides an estimate of potential waste inventory and waste form characteristics for the DOE UNF and HLW and a variety of commercial fuel cycle alternatives in order to support subsequent system-level evaluations of disposal system performance.
The report is intended to help assess and establish the technical basis for extended long‐term storage and transportation of used nuclear fuel. It provides: 1) an overview of the ISFSI license renewal process based on 10 CFR 72 and the guidance provided in NUREG‐1927; 2) definitions and terms for structures and components in DCSSs, materials, environments, aging effects, and aging mechanisms; 3) TLAAs and AMPs, respectively, that have been developed for managing aging effects on the SSCs important to safety in the dry cask storage system designs; and 4) AMPs and TLAAs for the SSCs that ar
The report presents information related to the development of a fundamental understanding of disposal-system performance in a range of environments for potential wastes that could arise from future nuclear fuel cycle alternatives. It addresses selected aspects of the development of computational modeling capability for the performance of storage and disposal options. Topics include radionuclide interaction with geomedia, colloid-facilitated radionuclide transport (Pu colloids), interaction between iodide (accumulate in the interlayer regions of clay minerals) and a suite of clay minerals
The assessment of generic EBS concepts and design optimization to harbor various disposal configurations and waste types needs advanced approaches and methods to analyze barrier performance. The report addresses: 1) Overview of the importance of THMC processes to barrier performance, and international collaborations; 2) THMC processes in clay barriers; 3) experimental studies of clay stability and clay-metal interactions at high temperatures and pressures; 4) thermodynamic modeling and database development; 5) Molecular Dynamics (MD) study of clay hydration at ambient and elevated temperatures; and 6) coupled thermal-mechanical (TM) and thermo-hydrological (TH) modeling in salt.
The Department of Energy’s Office of Nuclear Energy, Used Nuclear Fuel Disposition Research and Development Office (UFD), performs the critical mission of addressing the need for an integrated strategy that combines safe storage of spent nuclear fuel with expeditious progress toward siting and licensing a disposal facility or facilities. The UFD International Program plays a key role in this effort.
Irradiation is known to have a significant impact on the properties and performance of Zircaloy cladding and structural materials (material degradation processes, e.g., effects of hydriding). This UFD study examines the behavior and performance of unirradiated cladding and actual irradiated cladding through testing and simulation. Three capsules containing hydrogen-charged Zircaloy-4 cladding material have been placed in the High Flux Isotope Reactor (HFIR). Irradiation of the capsules was conducted for post-irradiation examination (PIE) metallography.
The U.S. Department of Energy Office of Nuclear Energy (DOE-NE), Office of Fuel Cycle Technology, has established the Used Fuel Disposition Campaign (UFDC) to conduct the research and development activities related to storage, transportation, and disposal of used nuclear fuel and high-level radioactive waste. The mission of the UFDC is to identify alternatives and conduct scientific research and technology development to enable storage, transportation and disposal of used nuclear fuel (UNF) and wastes generated by existing and future nuclear fuel cycles.
The purpose of ring compression testing is to generate data to support the development of the technical basis for extended storage and transportation of high-burnup fuel. This report highlights the results of completed Phase I testing of high-burnup M5® cladding and the revised three-year test plan. The goal of the ring compression testing is to identify process conditions that would minimize radial-hydride formation and the corresponding DBTT of high-burnup fuel cladding and to generate data and models to support the development of the technical basis for extended storage and transportation of high-burnup fuel.
The UFD Campaign is developing generic disposal system models (GDSM) of different disposal
environments and waste form options. Currently, the GDSM team is investigating four main disposal environment options: mined repositories in three geologic media (salt, clay, and granite) and the deep borehole concept in crystalline rock (DOE 2010d). Further developed the individual generic disposal system (GDS) models for salt, granite, clay, and deep borehole disposal environments.
The U.S. Department of Energy Office of Nuclear Energy (DOE-NE), Office of Fuel Cycle Technology, has established the Used Fuel Disposition Campaign (UFDC) to conduct the research and development activities related to storage, transportation, and disposal of used nuclear fuel and high-level radioactive waste. The mission of the UFDC is to identify alternatives and conduct scientific research and technology development to enable storage, transportation, and disposal of used nuclear fuel (UNF) and wastes generated by existing and future nuclear fuel cycles.
The report describes selected aspects of progress for four major tasks: (1) development of a detailed R&D plan for natural system evaluation and tool development; (2) in-depth analsis of key attributes and new concepts identified in the R&D plan; (3) preliminary demonstration of new modeling and experimental tools; and (4) conceptual design of a databse for natural system evaluation.
This study has been prepared by the Used Fuel Disposition (UFD) campaign of the Fuel Cycle Research and Development (FCR&D) program. The purpose of this study is to provide an estimate of the volume of low level waste resulting from a variety of commercial fuel cycle alternatives in order to support subsequent system-level evaluations of disposal system performance.
The engineered barrier system (EBS) plays a key role in the long-term isolation of nuclear waste in geological repository environments. This report focuses on the progress made in the evaluation of EBS design concepts, assessment of clay phase stability at repository-relevant conditions, thermodynamic database development for cement and clay phases, and THMC coupled phenomena along with the development of tools and methods to examine these processes; it also documents the advancements of the Disposal System Evaluation Framework (DSEF) for the development of repository design concepts and potential variants according to waste form and disposal environment characteristics.
The U.S. Department of Energy Office of Nuclear Energy (DOE-NE), Office of Fuel Cycle Technology (OFCT) has established the Used Fuel Disposition Campaign (UFDC) to conduct the research and development (R&D) activities related to storage, transportation and disposal of used nuclear fuel (UNF) and high level nuclear waste (HLW). The Mission of the UFDC is
The Used Fuel Disposition campaign (UFD) is selecting a set of geologic media for further study including variations on the design of the repository, the engineered barrier, and the waste. Salt, clay/shale, and granitic rocks are examined; granitic rocks are also the primary basement rock to consider for deep borehole disposal. UFD is developing generic system analysis capability and general experimental data related to mined geologic disposal in the three media (salt, clay/shale, and granitic rocks), and the use of deep boreholes in granitic rocks.
The primary objective of this report is to determine whether the existing Fuel Cycle Technologies (FCT) Quality Assurance Program Document (QAPD) is sufficient for work to be performed in the Used Fuel Disposition Campaign (UFDC), and where the existing QAPD is not sufficient, supply recommendations for changes to the QAPD to accommodate the UFDC. The FCT QAPD provides a sound and useable foundation for the implementation of QA for UFDC R&D activities, including the application of QA in a graded approach.
The management of used nuclear fuel and nuclear waste is required for any country using nuclear energy. This includes the storage, transportation, and disposal of low and intermediate level waste (LILW), used nuclear fuel (UNF), and high level waste (HLW). The Used Fuel Disposition Campaign (UFDC), within the U.S. Department of Energy (DOE), Office of Nuclear Energy (NE), Office of Fuel Cycle Technology (FCT), is responsible for conducting research and development pertaining to the management of these materials in the U.S.