Westinghouse 17x17 MOX PWR Assembly- Waste Package Criticality Analysis (SCPB: N/A)

This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development Department (WPDD) to compare the criticality potential of Westinghouse 17x17 mixed oxide (MOX) PWR fuel with the Design Basis spent nuclear fuel (SNF) analyzed previously (Ref. 5.1, 5.2). The basis of comparison will be the conceptual design Multi- Purpose Canister (MPC) PWR waste package concepts.

K-Infinite Trends with Burnup, Enrichment, and Cooling Time for BWR Fuel Assemblies

This report documents the work performed by ORNL for the Yucca Mountain Project (YMP) M&O contractor, Framatome Cogema Fuels. The goal of this work was to obtain k values for inf infinite arrays of flooded boiling-water-reactor (BWR) fuel assemblies as a function of various burnup/enrichment and cooling-time combinations. These scenarios simulate expected limiting criticality loading conditions (for a given assembly type) for drift emplacements in a repository. Upon

Summary Report of Commercial Reactor Criticality Data for McGuire Unit 1

The "Summary Report of Commercial Reactor Criticality Data for McGuire Unit 1" contains the detailed information necessary to perform commercial reactor criticality (CRC) analyses for the McGuire Unit 1 reactor.

Analysis of Fresh Fuel Critical Experiments Appropriate for Burnup Credit Validation

The ANS/ANS-8.1 standard requires that calculational methods used in determining criticality safety limits for applications outside reactors be validated by comparison with appropriate critical experiments. This report provides a detailed description of 34 fresh fuel critical experiments and their analyses using the SCALE-4.2 code system and the 27-group ENDF/B-IV cross-section library. The 34 critical experiments were selected based on geometry, material, and neutron interaction

Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology

This report, Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology, contains a summary of the laboratory critical experiment (LCE) analyses used to support the validation of the disposal criticality analysis methodology.

SCALE-4 Analysis of Pressurized Water Reactor Critical Configurations: Volume 4-Three Mile Island Unit 1 Cycle 5

The requirements of ANSI/ANS-8.1 specify that calculational methods for away-from-reactor criticality safety analyses be validated against experimental measurements. If credit is to be taken for the reduced reactivity of burned or spent fuel relative to its original "fresh" composition, it is necessary to benchmark computational methods used in determining such reactivity worth against spent fuel reactivity measurements. This report summarizes a portion of the ongoing effort to

slides - Extended Dry Storage and Transportation

Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013

Commercial Reactor Reactivity Analysis for Grand Gulf, Unit 1

The objective of this calculation is to document the Grand Gulf Unit 1 (GGl) reactivity calculations for sixteen critical statepoints in· cycles 4 through 8. The GG1 reactor is a boiling water reactor (BWR) owned and operated by Entergy Operations Inc. The Commercial Reactor Criticality (CRC) evaluations support the development and validation of the neutronic models used for criticality analyses involving commercial spent nuclear fuel to be placed in a geologic repository. This calculation is performed as part of the evaluation in the CRC program.

Probability of a PWR Uncanistered Fuel Waste Package Postclosure Criticality

The purpose of this calculation is to estimate the probability of criticality in a pressurized water reactor (PWR) uncanistered fuel waste package during the postclosure phase of the repository as a function of various waste package material, loading, and environmental parameters. Parameterization on the upper subcritical limit that is used to define the threshold for criticality will also be performed. The possibility of waste package misload due to human or equipment error during preclosure is also considered in estimating the postclosure criticality probability.

Radionuclide Screening

The waste forms under consideration for disposal in the repository at Yucca Mountain contain scores of radionuclides. It would be impractical and highly inefficient to model all of these radionuclides in a total system performance assessment (TSPA). Thus, the purpose of this radionuclide screening analysis is to remove from further consideration (screen out) radionuclides that are unlikely to significantly contribute to radiation dose to the public from a nuclear waste repository at Yucca Mountain.

Disposal Criticality Analysis for Aluminum-based Fuel in a Codisposal Waste Package - ORR and MIT SNF - Phase II

The objective of this analysis is to characterize the criticality safety aspects of a degraded Department of Energy spent nuclear fuel (DOESNF) canister containing Masachusetts Institute of Technology (MIT) or Oak Ridge Research (ORR) fuel in the Five Pack defense high level waste (DHLW) waste package to demonstrate concept viability related to use in the Minded Geologic Disposal System (MGDS) environment for the postclosure time frame.

slides - Certification/Licensing Approaches for High Burnup Spent Fuel

Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013

Limerick Unit 1 Radiochemical Assay Comparisons to SAS2H Calculations

The objective of the Limerick Unit 1 Radiochemical Assay Comparisons to SAS2H Calculations is to determine the accuracy of the SAS2H control module of the baselined modular code system SCALE, Version 4.4A (STN: 10129-4.4A-00), in predicting the isotopic concentrations of spent fuel, and to quantify the overall effect that the differences between the calculated and measured isotopic concentrations have on the system reactivity. The scope of this calculation covers eight different spent fuel samples from a fuel assembly that was irradiated in the Limerick Unit 1 boiling water reactor (BWR).

MCNP Evaluation of Laboratory Critical Experiments: Homogeneous Mixture Criticals

The purpose of this analysis is to document Waste Package Development Department (WPPD) MCNP evaluations of benchmark solution Laboratory Critical Experiments (LCE's). The objective of this analysis is to quantify the ability of the MCNP 4A (Reference 5.4) code system to accurately calculate the effective neutron multiplication factor (keff) for various measured critical (i.e., keff=1.0) configurations.

Sensitivity and Parametric Evaluations of Significant Aspects of Burnup Credit for PWR Spent Fuel Packages

Spent fuel transportation and storage cask designs based on a burnup credit approach must consider issues that are not relevant in casks designed under a fresh-fuel loading assumption. For example, the spent fuel composition must be adequately characterized and the criticality analysis model can be complicated by the need to consider axial burnup variations. Parametric analyses are needed to characterize the importance of fuel assembly and fuel cycle parameters on spent fuel

Nuclide Importance to Criticality Safety, Decay Heating, and Source Terms Related to Transport and Interim Storage of High-Burnup LWR Fuel

This report investigates trends in the radiological decay properties and changes in relative nuclide importance associated with increasing enrichments and burnup for spent LWR fuel as they affect the areas of criticality safety, thermal analysis (decay heat), and shielding analysis of spent fuel transport and storage casks. To facilitate identifying the changes in the spent fuel compositions that most directly impact these application areas, the dominant nuclides in each area have been identified and ranked by importance.

slides - Ideas for Obtaining Near-Term High Burn-up Used Fuel Data

Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013

Waste Packages and Source Terms for the Commercial 1999 Design Basis Waste Streams

This calculation is prepared by the Monitored Geologic Repository Waste Package Requirements & Integration Department. The purpose of this calculation is to compile source term and commercial waste stream information for use in the analysis of waste package (WP) designs for commercial fuel. Information presented will consist of the number of WPs, source terms, metric tons of uranium, and the average characteristics of assemblies to be placed in each WP design. The source terms provide thermal output, radiation sources, and radionuclide inventories.

Recommendations for Addressing Axial Burnup in PWR Burnup Credit Analyses

This report presents studies performed to support the development of a technically justifiable approach for addressing the axial-burnup distribution in pressurized-water reactor (PWR) burnup-credit criticality safety analyses. The effect of the axial-burnup distribution on reactivity and proposed approaches for addressing the axial-burnup distribution are briefly reviewed. A publicly available database of profiles is examined in detail to identify profiles that maximize the neutron multiplication factor, keff, assess its

LCE for Research Reactor Benchmark Calculations

The purpose of this calculation is to document the MCNP4B2L V evaluations of Laboratory Critical Experiments (LCEs) performed as part of the Disposal Criticality Analysis Methodology program. LCE evaluations documented in this report were performed for 182 different cases with varied design parameters. The objective of this analysis is to quantify the MCNP4B2LV code system's ability to accurately calculate the effective neutron multiplication factor (keff) for various critical configurations.

slides - CFD Best Practice Guidelines (NUREG-2152), Thermal Modeling Issues, and Generic Communications Related to Vacuum Drying Operations

Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013

Criticality Evaluation of Plutonium Disposition Ceramic Waste Form: Degraded Mode

The purpose of this calculation is to perform degraded mode criticality evaluations of plutonium disposed in a ceramic waste form and emplaced in a Monitored Geologic Repository (MGR). A 5 Defense High-Level Waste (DHLW) Canister Waste Package (WP) design, incorporating the can-in-canister concept for plutonium immobilization is considered for this calculation. Each HLW glass pour canister contains 7 tubes. Each tube contains 4 cans, with 20 ceramic disks (immobilized plutonium) in each.

Innovative Stakeholder Involvement Processes in Department of Energy Programs - A Selective Accounting

The Blue Ribbon Commission staff requested this paper cataloging innovative stakeholder involvement programs within the Department of Energy (DOE). I reviewed a variety of material on public involvement, including papers and presentations on stakeholder involvement in DOE programs, published presentations and comments to the BRC, and research reports on stakeholder and public involvement.

Criticality Safety and Shielding Evaluations of the Codisposal Canister in the Five-Pack DHLW Waste Package

The objective of this analysis is to characterize a codisposal canister containing MIT or ORR fuel in the Five-Pack defense high level waste (DHLW) waste package (WP) to demonstrate concept viability related to use in the Mined Geologic Disposal System (MGDS) environment for the postclosure time frame. The purpose of this analysis is to investigate the disposal criticality and shielding issues for the DHLW WP and establish DHLW WP and codisposal canister compatibility with the MGDS, and to provide criticality and shielding evaluations for the preliminary DHLW WP design.

Report on intact and Degraded Criticality for Selected Plutonium Waste Forms in a. Geologic Repository, Volume I: MOX SNF

As part of the plutonium waste form development and down-select process, repository analyses have been conducted to evaluate the long-term performance of these forms for repository acceptance. Intact and degraded mode criticality analysis of the mixed oxide (MOX) spent fuel is presented in Volume I, while Volume II presents the evaluations of the waste form containing plutonium immobilized in a ceramic matrix.