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The primary objective of this document is to provide sample applications o f selected sensitivity and uncertainty analysis techniques within the context of the radiological performance assessment process. These appl ications were drawn from the companion document Guide7 ines f o r S e n s i t i v i t y and Uncertainty AnaTIyses o f Low-Leve7 Radioactive Waste Performance Assessment Computer Codes (S. Maheras and M, Kotecki , DOE/LLW-100, 1990). Three techniques are illustrated in this document: one-factor-at-a-time (OFAT) analysis, fractional factorial design, and Latin hypercube sampling. sensitivity and uncertainty analysis at the early and latter stages o f the performance assessment process, and potentia'! pitfalls that can be encountered when applying the techniques, as opposed to the actual results, since the results are hypothetical and are not based on site-specific conditions. The report also illustrates the differences in The emphasis is on application of the techniques i i i EXECUTIVE SUMMARY Sensitivity and uncertainty analyses are a valuable, but sometimes neglected, part of the performance assessment (PA) process. In some cases, P A 4 s seen only as a method for demonstrating compliance with long-term dose or risk objectives after a facility has been designed. Furthermore, some view PA as a requirement that must be done, without consideration of the other benefits that can be obtained. used as a management tool during all stages of the licensing process. By indicating the relative impact o f individual design and site Characterization parameters on disposal system performance, sensitivity/uncertainty analysis results can provide justificatior for specific activities based on quantitative, performance-based measures. Of course, technical judgement and qualitative factors (i.e., reality checks) must also be considered because o f the uncertainties involved and complexity of the processes. understanding of the behavior of a system makes it easier for management to defend decisions related to continuing or discontinuing funding for specific activities. PA (through the use of sensitivity/uncertainty analysis) can be In any case, improved The use o f sensitivityluncertainty analyses in the PA process has two primary benefits: e e Cost savings obtained by focusing site characterization, design, and modeling efforts on the site data, design features, and transport pathways that have the greatest impacts on facility performance Quantification o f the uncertainty associated with PA predictions used to demonstrate compl iance, Furthermore, the U.S. Nuclear Regulatory Commission (NRC) has emphasized the need for sensitivity/uncertainty analyses by including a requirement in the Standard Format and Content f o r a License A p p l i c a t i o n for a Low-Levell R a d i o a c t i v e Waste Disposall F a c i l i t y (NUREG-1199, Rev. 1; NRC 1988, pp. 6-7 and 6-10). V The primary objective of this document is to provide sample applications of selected sensitivity and uncertainty analysis techniques within the contex...

Agency for protectionof the general public. The calculations involved modeling the transport of radionuclidesfrom buried waste, to surface soil and subsurfacemedia, and eventuallyto members of the general public via air, ground water, and food chain pathways. Projectionsof doses were made for both offsite receptors and individuals intrudingonto the site after closure. In addition, uncertainty analyses were performed.Results of calculationsmade using nominal data indicate that the radiologicaldoses will be below appropriateradiologicalcriteria throughout operations and after closure of the facility.Recommendationswere made for future performanceassessment calculations. Three time periods of concern were addressed in this evaluation of the RWMC:I. The operational period, 1964 through 2089, during which radioactivewaste is actively disposed of at the facility. 2.The institutionalperiod, 2089 through 2189, which follows site clo_ure and during which periodic maintenance and monitoring activities are conducted. The facility is assumed to be stabilized but is still part of the INEL reservation and is fenced and patrolled. 3.The post-institutionalperiod, 2189 through 11975, during which the facility is no longer maintainedby the DOE and may be accessible to the public. iii DRAFT boundary at the location of maximum concentrationof airborne radionuclides in the transport medium of concern (i.e., air or ground water).The second type of receptor evaluated is an intruder. This hypotheticalreceptor is assumed to inadvertentlyintrude on the RWMC during the post-institutionalcontrol period. Two general kinds of scenarios were evaluated. The first is an agriculture scenario in which the receptor obtains half of his produce from farming at the RWMC. This individualalso drinks water from a well drilled at the edge of the waste. The second is an acute exposure scenario that includes a constructionscenario and a well-drillingscenario. In the construction scenario, the receptor is an individualwho is building a house at the RWMC and is exposed to contaminatedsoil while excavating the cellar. In the well-drilling scenario, the receptor is exposed to contaminateddrill cuttings that are deposited in a mud pit.Results of the monitoring, special studies, and modeling efforts to date indicate that the greatest potential for transport of radionuclides from the RWMC to offsite receptors (now and in the future) is via airborne transport of resuspended contaminatedsurface soil particles and ground water transport of radionuclidesleached from buried waste. For this reason, the performance assessmentonly addresses these two transport pathways.The exposure pathways evaluated include ingestion of food and water, inhalation of contaminatedairborne particulates,and external exposure to radionuclidesin air and soil. The agriculturalproducts consumed by the general public are contaminatedvia food chain transport of radionuclides deposited from air onto soil or plant surfaces. Projections of radionuclideconcentrationsin surface soil and subsurfacemedi...

This report fulfills the requirements for milestone M3FT-14PN0813032 "Fuel Assembly Test Plan" under work package FT-14PN081303. The objective of the rail shock and vibration tests is to complete the framework needed to quantify loads of fuel assembly components that are necessary to guide materials research and establish a technical basis for review organizations such as the U.S. Nuclear Regulatory Commission (NRC). A significant body of experimental and numerical modeling data exists to quantify loads and failure limits applicable to normal conditions of transport (NCT) rail transport, but the data are based on assumptions that can only be verified through experimental testing. The test options presented in this report represent possible paths for acquiring the data that are needed to confirm the assumptions of previous work, validate modeling methods that will be needed for evaluating transported fuel on a case-by-case basis, and inform material test campaigns on the anticipated range of fuel loading. The ultimate goal of this testing is to close all of the existing knowledge gaps related to the loading of used fuel under NCT conditions and inform the experiments and analysis program on specific endpoints for their research. The U.S. Department of Energy Office of Nuclear Energy (DOE-NE), Office of Fuel Cycle Technology, 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 Storage and Transportation staff within the UFDC are responsible for addressing issues regarding the extended or long-term storage of UNF and its subsequent transportation. Until a disposition pathway, e.g., recycling or geologic disposal, is chosen and implemented, the storage periods for UNF will likely be longer than were originally intended.

This report fulfills the M4 milestone M4FT-13OR08220112, "Report Documenting Experimental Activities." The purpose of this report is to document the results of a literature review conducted of studies related to the vibration and shock associated with the normal conditions of transport for rail shipments of used nuclear fuel from commercial light-water reactors. As discussed in Adkins (2013), the objective of this report is to determine if adequate data exist to realistically evaluate the impacts of the shock and vibration associated with the normal conditions of transport on commercial light-water reactor used nuclear fuel shipped in current-generation high-capacity rail transportation casks. The literature review concentrated on papers and reports related to the transport of used nuclear fuel, radioactive waste, or other radioactive material, in part because of the weight associated with commercial light-water reactor used nuclear fuel rail transportation casks, which is about 300,000 lb., and because the weight of the transportation cask on a railcar directly affects the magnitude of vibrations and shock imparted to the used nuclear fuel contained in the transportation cask. In addition, the railcars that will be used by the U.S. Department of Energy to ship transportation casks containing used nuclear fuel from commercial light-water reactors are required to meet American Association of Railroads (AAR) Standard S-2043 (AAR 2008). Therefore, searches were also conducted for studies where the railcar met AAR Standard S-2043. Because the focus of the modeling described in Adkins (2013) is at the fuel assembly and fuel rod levels, studies where accelerations were measured on fuel assemblies or fuel rods were also especially relevant. During the literature review conducted of studies related to the vibration and shock associated with the normal conditions of transport for rail shipments of used nuclear fuel, over 200 documents were collected from a wide variety of sources, including studies performed by Sandia National Laboratories, the Hanford Engineering and Development Laboratory, Ontario Hydro, Battelle Columbus Laboratories, and the Savannah River Site, as well as studies performed by other investigators. The results of the literature review follow.  There were few recent studies of the shock and vibration associated with the normal conditions of transport. Most of the studies that were related to the shipment of used nuclear fuel, radioactive waste, or radioactive material were published in the 1960s, 1970s, and 1980s. Relatively few studies were published after the mid-1990s.  No studies were found that evaluated a rail transportation cask or other cargo that was similar in weight to the weight of a commercial light-water reactor used nuclear fuel rail transportation cask, about 300,000 lb. The largest transportation casks evaluated were in a study by Prulhiere and Israel (1980), where the TN 12 transportation cask, weighing 220,000 lb., was evaluated; and in a study by Pujet and Malesys (1989), where the...