No abstract

The cancellation of the Yucca Mountain repository program in the Unites States raises the prospect of very long-term storage (i.e., >120 years) and deferred transportation of used fuel at the nuclear power plant sites. While long-term storage of used nuclear fuel in dry cask storage systems (DCSSs) at Independent Spent Fuel Storage Installations (ISFSIs) is already a standard practice among U.S. utilities, recent rule-making activities of the U.S. Nuclear Regulatory Commission (NRC) indicated additional flexibility for the NRC licensees of ISFSIs and certificate holders of the DCSSs to request initial and renewal terms for up to 40 years. The proposed rule also adds a requirement that renewal applicants must provide descriptions of aging management programs (AMPs) and time-limited aging analyses (TLAAs) to ensure that the structures, systems, and components (SSCs) that are important to safety in the DCSSs will perform as designed under the extended license terms. This paper examines issues related to managing aging effects on DCSSs for very long-term storage (VLTS) of used fuels, capitalizing on the extensive knowledge and experience accumulated from the work on aging research and life cycle management at Argonne National Laboratory (ANL) over the last 30 years. The technical basis for acceptable AMPs and TLAAs is described, as are generic AMPs and TLAAs that are being developed by Argonne under the support of the U.S. Department of Energy (DOE) Used Fuel Disposition Campaign for R&D on extended long-term storage and transportation.

The Department of Energy has established guidelines for the qualifications and training of technical experts preparing and reviewing the safety analysis report for packaging (SARP) and transportation of radioactive materials. One of the qualifications is a working knowledge of, and familiarity with the ASME Boiler and Pressure Vessel Code, referred to hereafter as the ASME Code. DOE is sponsoring a course on the application of the ASME Code to the transportation packaging of radioactive materials. The course addresses both ASME design requirements and the safety requirements in the federal regulations. The main objective of this paper is to describe the salient features of the course, with the focus on the application of Section III, Divisions 1 and 3, and Section VIII of the ASME Code to the design and construction of the containment vessel and other packaging components used for transportation (and storage) of radioactive materials, including spent nuclear fuel and high-level radioactive waste. The training course includes the ASME Code-related topics that are needed to satisfy all Nuclear Regulatory Commission (NRC) requirements in Title 10 of the Code of Federal Regulation Part 71 (10 CFR 71). Specifically, the topics include requirements for materials, design, fabrication, examination, testing, and quality assurance for containment vessels, bolted closures, components to maintain subcriticality, and other packaging components. The design addresses thermal and pressure loading, fatigue, nonductile fracture and buckling of these components during both normal conditions of transport and hypothetical accident conditions described in 10 CFR 71. Various examples are drawn from the review of certificate applications for Type B and fissile material transportation packagings.

The U.S. Department of Energy (DOE) Packaging Certification Program (PCP), Office of Packaging and Transportation, Office of Environmental Management, has sponsored a suite of training courses that are conducted annually by Argonne National Laboratory (Argonne) in support of safety and security of nuclear and other radioactive material packages. One of these courses conducted by Argonne since 2000 is the Application of the ASME Code to Radioactive Material Transportation Packaging, which was expanded significantly in 2014 to include dry storage casks, resulting in a change in course title to the Application of the ASME Code to Radioactive Material Packaging/Cask. The purpose of the course is to provide guidance for the application of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV) Code (“ASME Code”) to transportation packaging and storage cask of radioactive materials, including used (or spent) nuclear fuel and high-level waste, and to facilitate the design, fabrication, examination, and testing of packagings and casks. Both regulatory requirements in 10 CFR Parts 71 and 72 and the ASME Code requirements for transportation and storage containments are addressed, with emphasis on the Code Section III, Division 3, “Containments for Transportation and Storage of Spent Nuclear Fuel and High Level Radioactive Material and Waste.” Among the specific topics covered are the application of the ASME Code requirements to structural materials, containments, loading and design; the design of containment internal support structures and buckling analysis; fabrication, welding, examination, and test requirements; quality assurance; physical testing, structural and thermal modeling and analysis considerations; and containment, shielding, and criticality analysis considerations. Special topics covered include non-Code materials, hydrogen gas generation, and aging management for extended long-term storage of used fuel and subsequent transportation. The expanded training course was offered in June 2014 at Argonne with 27 participants representing mainly industry and government agencies. On the basis of the feedback and course evaluation by the participants, the course may be expanded from 3 to 4.5 days in the future to allow more time for in-class discussion and exercises, as well as to include additional topics related to aging management for extended long-term storage of used fuel and its post-storage transportation. The course provides insight into the DOE and the U.S. Nuclear Regulatory Commission (NRC) transportation and storage cask certification processes. The target audience is DOE, DOE contractors, other agency personnel, and commercial transportation packaging and storage cask engineering employees. Those responsible for designing, fabricating, testing, or packaging and casks, as well as preparing or reviewing the associated Safety Analysis Reports, will also benefit from the course.

The Department of Energy (DOE) has established guidelines for qualifications and training of the technical experts preparing and reviewing the safety analysis reports for packaging (SARP) and transportation of radioactive materials. One of the qualifications is working knowledge of, and familiarity with the quality assurance (QA) requirements in Subpart H of Title 10 of the Code of Federal Regulations Part 71. DOE is sponsoring a course on quality assurance for radioactive material transportation packaging. The objective of this paper is to describe the salient features of the course, the purpose of which is to provide QA training and practical experience that are required to develop and implement a QA plan or prepare the QA chapter of a SARP for the design, fabrication, assembly, testing, maintenance, repair, modification, and use of the packaging. The applicable QA requirements from DOE orders, federal regulations, and NRC regulatory guides will be highlighted, along with a graded approach to selected QA elements from Subpart H of 10 CFR Part 71. The paper will also briefly discuss ASME NQA-1 for Type B and fissile material packaging, current issues resulting from the different emphasis between a compliance-based QA program (in Subpart H, 10 CFR 71) for packaging and a performance-based QA program for DOE nuclear facilities (based on 10 CFR 830, “Nuclear Safety Management”), and the final rule changes in 10 CFR 71 that became effective on October 1, 2004.