The purpose of this research effort is to determine the effects of canister/cask vacuum drying and storage on radial hydride precipitation in high‐burnup (HBU) pressurized water reactor (PWR) cladding alloys during cooling for a range of peak drying‐storage temperatures, internal gas pressures, and hoop stresses. The HBU PWR cladding alloys have a wide range of hydrogen contents and varying hydride morphology after in‐reactor service.
This report describes the current status of international collaboration regarding geologic disposal research in the Used Fuel Disposition (UFD) Campaign. To date, UFD’s International Disposal R&D Program has established formal collaboration agreements with five international initiatives and several international partners, and has started several specific collaborative R&D activities. These international activities include testing and modeling studies and address the following key research areas: Near-Field Perturbation, Engineered Barrier Integrity, Radionuclide Transport, and
Radioactive waste disposal in shale/argillite rock formations has been widely considered given its desirable isolation properties, e.g., low permeability, potential geochemically reduced conditions, anomalous groundwater pressures, and widespread geologic occurrence.
The collaborative approach to the glass and metallic waste form degradation modeling activities includes process model development (including first-principles approaches) and model integration—both internally among developed process models and between developed process models and PA models, and cross campaign integration between activities in the Used Fuel Disposition (UFD) Campaign and the Separations (to be Materials Recovery) and Waste Forms (SWF=>MRWF) Campaign. Experimental work is conducted within the UNFD area and results are utilized in development efforts. The primary outputs
[In Support of a Comprehensive National Nuclear Fuel Cycle Strategy, Volumes I and II (Appendices)]
This study provides a technical basis for informing policy decisions regarding strategies for the management and permanent disposal of spent nuclear fuel (SNF) and high-level radioactive waste (HLW) in the United States requiring geologic isolation.
This Test Plan for the High Burnup Dry Storage Research Project (HDRP) outlines the data to be collected, the high burnup fuel to be included, and the storage system design, procedures, and licensing necessary for implementation.
Clay and granitic units are potential host media for future repositories for used nuclear fuel. The report addresses the representation and characterization of flow in these two media within numerical process models. In low permeability crystalline rock, flow is primarily in relatively sparse networks of fractures.
The objective of this work is to develop a spatial database that integrates both geologic data for alternative host-rock formations and information that has been historically used for siting guidelines, both in the US and other countries. The Used Fuel Disposition Campaign (UFDC) is considering three alternative geologic host rocks for mined repositories (granitic / crystalline, salt, and clay / shale) and crystalline basement rock for deep borehole disposal. This report documents progress in populating a GIS Database with information concerning the distribution of alternative host rock
International research collaborations on deep geological disposition of nuclear waste are a key aspect of the nation’s strategy to investigate disposal design concepts in geologic settings considered by other countries. This report centers on results obtained on THM simulations, reactive transport model development, and engineered barrier system (EBS) material characterization studies.
Active participation in international R&D is crucial for achieving the Used Nuclear Fuel Disposition long-term goals of conducting experiments to fill data needs and confirm advanced modeling approaches and of having a robust modeling and experimental basis for evaluation of multiple disposal system options.
This report documents the first phase of a multi-year project to understand the technical feasibility and logistical implications of direct disposal of spent nuclear fuel in existing dual-purpose canisters (DPCs) and other types of storage casks.
Contributions are described for the development of an enhanced generic disposal system modeling and analysis capability that takes advantage of high-performance computing (HPC) environments to simulate the important multi-physics phenomena and couplings associated with a geologic repository for UNF and HLW.
Deep borehole disposal is one alternative for the disposal of spent nuclear fuel and other radioactive waste forms; identifying a site or areas with favorable geological, hydrogeological, and geochemical conditions is one of the first steps to a demonstration project.
The report describes the strategy for coupling process level models to produce an integrated Used Fuel Degradation Model (FDM), and addresses fractional degradation rate, instant release fractions, other continuum modeling approaches, and experimental support.
This report provides results of the initial demonstration of the modeling capability developed to perform preliminary deterministic evaluations of moderate-to-high burnup used nuclear fuel (UNF) mechanical performance under normal conditions of storage (NCS) and transport (NCT).
This study contributes to investigation and better understanding of cladding (High Flux Isotope Reactor used to simulate the effects of high burnup on fuel cladding) materials performance in extended storage and transportation through the conduct of small scale and separate effects tests (SET).
Enginerred Barrier Systems (EBS) model evaluation and development is fundamental to the design and analysis of disposal concepts for generic repository systems; this report centers on progress made on modeling and experimental approaches to analyze physical and chemical interactions affecting clay barrier performance.
Experiments were used to examine water content in Permian salt samples including impact of variation in thermal regime on water content of evaporites and other mineral species, behavior of brine inclusions in salt, and evolution of the gas/liquid brine/salt system.
This work on the natural barrier system is conducted to reduce uncertainty in natural system performance and to fully exploit the credits that can be taken for the natural system barrier; several potential enhancements to describing barrier performance capabilities are presented.
Shale and clay-rich rock formations have been considered as potential host rocks for geological disposal of high-level radioactive waste throughout the world: modeling thermal, hydrological, mechanical, and chemical (THMC) of the near field of generic clay repository is discussed.