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Howard, Rob L.

Publications and source records attributed to Howard, Rob L..

11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Water Migration and Swelling in Engineered Barrier Materials for Radioactive Waste Disposal

Deep, underground repositories are needed to isolate radioactive waste from the biosphere. Because bentonite is an integral component of many multibarrier repository systems, information on the hydraulic behavior of bentonite is crucial for modeling the long-term viability of such systems. In this paper the hydraulic behavior of bentonite samples was analyzed as a function of aggregate size, and samples were subjected to hydrothermal treatments involving contact with NaCl, KCl, and deionized water. Neutron and X-ray imaging were used to quantify water sorption into packed bentonite samples and bentonite swelling into the water column. The distance between the original clay-water interface and the wetting front was determined as a function of time. Average water uptake exhibited a square-root-of-time dependence in freshly prepared samples, but more variable rates were observed for samples previously in contact with water. The radiography was supported by small-angle neutron scattering analysis and ultra-small-angle neutron scattering analysis of aggregate size distributions and by inelastic neutron scattering to understand the physicochemical environment of the sorbed water. Results showed that hydrothermal treatment with KCl had the greatest effect of increased water transport in the bentonite, possibly as a result of the interaction of K + with smectite layers in the clay.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Summary of Investigations on Technical Feasibility of Direct Disposal of Dual-Purpose Canisters

This report is a revision of the Fiscal Year (FY)-15 summary report on the investigations on technical feasibility of direct disposal of dual-purpose canisters (DPCs) in a geological repository. Notable progress has been made in the postclosure criticality area supporting direct disposal of DPCs in FY-16 and FY-17. As such, this revision updates the postclosure criticality related studies to capture the advances made over the last two FYs.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Performance Specification for Standardized Transportation, Aging, and Disposal Canister Systems (Rev.2)

This performance specification document addresses use of a standardized transportation, aging, and disposal (STAD) canister system in the spent nuclear fuel (SNF) waste management system. This document was developed to support STAD canister system studies and potential research, development, and demonstration activities. Requirements in this specification may evolve with time based on results from analyses, experiments, design studies, system evaluations and demonstrations, as well as other factors. A STAD canister system consists of a canister, together with a storage or aging overpack/module/vault, a shielded transfer cask (STC), a site transporter, a transportation overpack, and a transportation skid. Three sizes of circular cross section STAD canister variants are specified in this document. The small STAD canister capacity is four pressurized water reactor (PWR) or nine boiling water reactor (BWR) SNF assemblies. The medium STAD canister capacity is 12 PWR or 32 BWR SNF assemblies. The large STAD canister capacity is 21 PWR or 44 BWR SNF assemblies. Using standardized canisters for SNF facilitates the interface between storage at an independent spent fuel storage installation (ISFSI) or a DOEowned interim storage facility (ISF), transportation between facilities, and disposal at a repository. Multiple STAD canisters may be stored in a single storage overpack and/or a single transportation overpack. The US Nuclear Regulatory Commission (NRC) requirements currently used for storage and transportation are adopted for the STAD canister system. Approved approaches (guidance) in NRC storage and transportation documents are also adopted as requirements for the STAD canister system to facilitate obtaining NRC Certificates of Compliance (CoCs) for STAD canister systems. Performance specifications in this document are also informed by STAD canister disposability in various geologic media and consideration of ISF (and geologic repository) handling facility design, operations, and licensing requirements.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Rationale for the Performance Specification for Standardized Transportation, Aging, and Disposal Canister Systems (Rev.1)

This document provides the rationale for the specifications for the standardized transportation, aging, and disposal (STAD) canister systems provided in Performance Specification for Standardized Transportation, Aging, and Disposal Canister Systems, FCRD-NFST-2014-000579, Rev. 2, referred to as STAD Spec herein. The STAD Spec was developed to support STAD canister system studies and potential research, development, and demonstration activities. Requirements in the specification may evolve with time based on results from analyses, experiments, design studies, system evaluations and demonstrations, as well as other factors. The STAD canister system consists of a canister, together with a storage or aging overpack/module/vault, a shielded transfer cask (STC), a site transporter, a transportation overpack, and a transportation skid. Three sizes of circular cross section STAD canister variants are specified. The small STAD canister capacity is four pressurized water reactor (PWR) or nine boiling water reactor (BWR) spent nuclear fuel (SNF) assemblies. The medium STAD canister capacity is 12 PWR or 32 BWR SNF assemblies. The large STAD canister capacity is 21 PWR or 44 BWR SNF assemblies. There are 60 specifications in the STAD Spec that cover the STAD canister general design attributes, canister safety functional requirements, operational considerations, materials, storage and aging system requirements, and transportation system requirements. The 60 specifications are derived from regulatory requirements, regulatory guidance, STAD canister disposability considerations, and interim storage facility (ISF) and geologic repository handling facility considerations.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

A Review of Multipurpose Canister Concepts for Standardization in the Waste Management System

Since the early 1980s, the federal government and individual utilities have put forth considerable effort to develop a canister for spent nuclear fuel (SNF) that could be used as part of a dry storage system, transportation system, and disposal system without having to be reopened. While the terminology for this type of canister has changed over the years, the underlying concept and purpose have not. These efforts and ongoing activities in this area are highlighted, expanding upon several previous works [1, 2, 3].During development of dry storage systems in the 1980s, there was growing interest in triple-purpose (storage, transportation, and disposal) canister concepts, and preliminary studies were conducted [4, 5]. That interest evolved into a project to develop a multipurpose canister (MPC) in the 1990s [6, 7, 8]. After the defunding of that project, the concept lived on in a canister system for US DOE–owned fuel from the mid 1990s to the early 2000s. The commercial spent fuel version of the concept resurfaced in the mid-2000s as the transportation aging and disposal (TAD) canister [2, 9, 10]. After the halting of the Yucca Mountain project, the specific implementation of triple-purpose canisters was reevaluated. This re-evaluation resulted in the standardized transportation aging and disposal (STAD) canister conceptual design and evaluation effort [11]. Each of these efforts is reviewed and summarized.

Cumberland, Riley↗
DOE OSTI2015

Lessons learned from CIRFT testing on SNF vibration integrity study

A cyclic integrated reversible-bending fatigue tester (CIRFT) was developed to support U.S. NRC and DOE Used Fuel Disposition Campaign studies on high burn-up (HBU) spent nuclear fuel (SNF) transportation during normal conditions of transport (NCT). Two devices were developed; the first CIRFT was successfully installed and operated in the ORNL hot-cells in September 2013. Since hot cell testing commenced several HBU SNF samples from both Zr-4 and M5 clads were investigated. The second CIRFT device was developed in February 2014, and has been used to test clad/fuel surrogate rods (stainless steel with alumina pellet inserts). The second CIRFT machine has also been used for sensor development and test sensitivity analyses, as well as loading boundary condition parameter studies. The lessons learned from CIRFT testing will be presented in this paper.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2014

Reversal bending fatigue test system for investigating vibration integrity of spent nuclear fuel during transportation

Transportation packages for spent nuclear fuel (SNF) must meet safety requirements under normal and accident conditions as specified by federal regulations. During transportation, SNF experiences unique conditions and challenges to cladding integrity due to the vibrational and impact loading during road or rail shipment. Oak Ridge National Laboratory (ORNL) has been developing testing capabilities that can be used to improve the understanding of the impacts on SNF integrity due to vibration loading, especially for high burn-up SNF in normal transportation operation conditions. This information can be used to meet the nuclear industry and U.S.Nuclear Regulatory Commission needs in the area of safety and security of SNF storage and transportation operations. The ORNL developed test system can perform reversal bending fatigue testing to evaluate both the static and dynamic mechanical response of SNF rods under simulated loads. The testing apparatus is also designed to meet the challenges of hot cell operation, including remote installation and detachment of the SNF test specimen, in situ test specimen deformation measurement, and implementation of a driving system suitable for use in a hot cell. The system contains a U frame set-up equipped with uniquely designed grip rigs to protect the SNF rod sample and to ensure valid test results, and uses three specially designed linear variable differential transformers to obtain the in situ curvature measurement. A variety of surrogate test rods have been used to develop and calibrate the test system as well as in performing a series of systematic cyclic fatigue tests. The surrogate rods include stainless steel (SS) cladding, SS cladding with cast epoxy and SS cladding with alumina pellet inserts simulating fuel pellets. Testing to date has shown that the interface bonding between the SS cladding and the alumina pellets has a significant impact on the bending response of the test rods as well as their fatigue strength. The failure behaviours observed from tested surrogate rods provide a fundamental understanding of the underlying failure mechanisms of the SNF surrogate rod under vibration,which has not been achieved previously. The newly developed device is scheduled to be installed in the hot cell in summer 2013 to test high burn-up SNF.

high burn up fuel↗
DOE OSTI2013

Post-Irradiation Examination of Zircaloy-4 Samples in Target Capsules and Initiation of Bending Fatigue Testing for Used Nuclear Fuel Vibration Integrity Investigations (FY 2013 Summary Report)

This report documents ongoing work performed at Oak Ridge National Laboratory (ORNL) for the Department of Energy, Office of Fuel Cycle Technology Used Fuel Disposition Campaign (UFDC), and satisfies the deliverable for milestone M2FT-13OR0805041, “Data Report on Hydrogen Doping and Irradiation in HFIR.” This work is conducted under WBS 1.02.08.05, Work Package FT-13OR080504 ST “Storage and Transportation-Experiments – ORNL.” The objectives of work packages that make up the S&T Experiments Control Account are to conduct the separate effects tests (SET) and small-scale tests that have been identified in the Used Nuclear Fuel Storage and Transportation Data Gap Prioritization (FCRD-USED-2012-000109). In FY 2013, the R&D focused on cladding and container issues and small-scale tests as identified in Sections A-2.9 and A-2.12 of the prioritization report.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2012

Transportation Storage Logistics (TSL) Model Data Management Manual

The Transportation Storage Logistics (TSL) Model Data Management Manual describes the SQL Server database that is used by the TSL model to house reference data as well as the scenario data. The manual is a reference document, subject to change as the model evolves.

Busch, Ingrid Karin↗
DOE OSTI2012

Transportation Operations Model (TOM) Technical Manual

The Transportation Operations Model (TOM) is a component of the Transportation Storage Logistics (TSL) model, which assists the analyst in planning and evaluating scenarios for the transportation and storage of spent nuclear fuel (SNF). TOM was originally developed for the DOE’s Office of Civilian Radioactive Waste Management (OCRWM) in 2006. TOM provides detailed modeling of the transportation of spent nuclear fuel and the assets needed to accomplish that. This Transportation Operations Model (TOM) Technical Manual presents the theory and algorithm behind the model. Further information on the Transportation Storage Logistics model is available in the Transportation Storage Logistics Users’ Manual, and in the Transportation Storage Logistics Model Data Management Manual.

Busch, Ingrid Karin↗