slides - Extended Dry Storage and Transportation
slides - Extended Dry Storage and Transportation
Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013
Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013
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.
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.
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.
The Department of Energy’s Office of Fuel Cycle Technologies (FCT) in the Office of Nuclear Energy (DOE-NE) has conducted a technical review and assessment of the total current inventory [~70,150 MTHM (metric ton of heavy metal) as of 2011] of domestic discharged used nuclear fuel (UNF) and estimated that up to ~1700 MTHM of existing commercial UNF should be considered for retention to support research, development, and demonstration (RD&D) needs and national security interests.
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.
Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013
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).
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.
NRC/NEI, January 24, 2014 Public Meeting Presentations
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
This report presents a comprehensive description of the post-closure radiological safety assess- ment of a repository for spent fuel (SF), vitrified high-level waste (HLW) from the reprocessing of spent fuel and long-lived intermediate-level waste (ILW), sited in the Opalinus Clay of the Zürcher Weinland in northern Switzerland. This assessment has been carried out as part of the technical basis for Project Entsorgungsnachweis1, which also includes a synthesis of informa- tion from geological investigations of the Opalinus Clay and a report on engineering feasibility.
DOE decided to terminate the Yucca Mountain repository program because, according to DOE officials, it is not a workable option and there are better solutions that can achieve a broader national consensus. DOE did not cite technical or safety issues. DOE also did not identify alternatives, but it did create a Blue Ribbon Commission to evaluate and recommend alternatives.
This evaluation investigates the potential benefits of separating the transuranic elements from spent reactor fuel before it is disposed of in geologic repositories. It addresses the question: Would the benefits to radioactive waste disposal justify both processing the spent fuel and deploying liquid metal reactors (LMRs) to transmute the separated transuranics?
http://www.epri.com/abstracts/Pages/ProductAbstract.aspx?ProductId=NP-7…
Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013
A brief history of operation, decommissioning, and the interim storage of spent nuclear fuel
The Nuclear Waste Administration Act of 2013 discussion draft is intended to implement the recommendations of the Blue Ribbon Commission on America’s Nuclear Future to establish a nuclear waste administration and create a consent-based process for siting nuclear waste facilities. The bill enables the federal government to fulfill its commitment to managing nuclear waste, ending the costly liability the government bears for its failure to dispose of commercial spent fuel.
The purpose of this engineering calculation is to provide the chemical composition for the Department of Energy (DOE) Savannah River Site (SRS) High-Level Waste (HLW) glass. Since the glass is to be co-disposed with other DOE spent nuclear fuels (SNFs) in the Monitored Geologic Repository (MGR), its chemical composition is needed for the design of the co-disposal canisters and waste packages in term of criticality and degradation.
Taking credit for the reduced reactivity of spent nuclear fuel in criticality analyses is referred to
as burnup credit. Criticality safety evaluations employing burnup credit require validation of the
depletion and criticality calculation methods and computer codes with available measurement
data. To address the issues of burnup credit criticality validation, the U.S. Nuclear Regulatory
Commission initiated a project with Oak Ridge National Laboratory to (1) develop and establish
Several rod consolidation systems have been demonstrated in the United States with simulated boiling water reactor (BWR) and pressurized water reactor (PWR) fuel. The first U.S. consolidation of irradiated fuel was successfully demonstrated with four PWR fuel assemblies at the Oconee Nuclear Station in October-November 1982 (1-3) and with one PWR fuel assembly at Maine Yankee in August 1983(4). Maine Yankee has received approval from the U.S. Nuclear Regulatory Commission (NRC) to consolidate up to 20 fuel assemblies(5).
This vintage 1990 document presents the results of WESTON'S preliminary assessment of the feasibility of several alternative fuel-transfer and storage concepts that have the potential for early spent-fuel acceptance at an MRS facility. The feasibility study was part of a series of studies conducted by the U.S. Department of Energy (DOE) during the late 1980's and early 1990's in an effort to establish an MRS design configuration.
The objective of this calculation is to evaluate the peak temperatures due to thermal loading and boundary conditions of the TAD Waste Package design under nominal Monitored Geologic Repository conditions.
Presented at the NEI Used Fuel Management Conference, St. Petersburg, FL, May 7-9, 2013
Unirradiated reactor fuel has a well-specified nuclide composition that provides a
straightforward and bounding approach to the criticality safety analysis of transport and storage
casks. As the fuel is irradiated in the reactor, the nuclide composition changes and, ignoring
the presence of burnable poisons, this composition change will cause the reactivity of the fuel to
decrease. Allowance in the criticality safety analysis for the decrease in fuel reactivity resulting
The purpose of this calculation is to establish the relative change in the effective neutron multiplication factor (keff) due to the use of MCNP unique identifiers (ZAIDs) in Nuclear Criticality Calculations for Canister-Based Facilities - DOE SNF (Reference 2.2.1, Attachment 3, MCNP inputs.zip) that are different to the ZAIDs used in the Analysis of Critical Benchmark Experiments and Critical Limit Calculation for DOE SNF (Reference 2.2.5, Table 5-3).