slides - NRC Management Perspectives
slides - NRC Management Perspectives
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
This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development (WPD) department to provide an evaluation of the criticality potential within a waste package having some or all of its contents degraded by corrosion and removal of neutron absorbers. This analysis is also intended to provide an estimate of the consequences of any internal criticality, particularly in terms of any increase in radionuclide inventory. These consequence estimates will be used as part of the WPD input to the Total System Performance Assessment.
The purpose of this calculation is to perform partially and fully degraded mode criticality evaluations of plutonium disposed of in a ceramic waste form and emplaced in a Monitored Geologic Repository. The partially degraded mode is represented by the immobilized plutonium ceramic discs piled in the bottom of the waste package (WP) while neutron absorbers begin to leach out of the discs.
The Disposal Subcommittee of the Blue Ribbon Commission on America’s Nuclear Future (BRC) addressed a wide-ranging set of issues, all bearing directly on the central question: “How can the United States go about establishing one or more disposal sites for high-level nuclear wastes in a manner and within a timeframe that is technically, socially, economically, and politically acceptable?”
The Global Nuclear Energy Partnership (GNEP) Program, a United States (U.S.) Department of
Energy (DOE) program, is intended to support a safe, secure, and sustainable expansion of
nuclear energy, both domestically and internationally. Domestically, the GNEP Program would
promote technologies that support economic, sustained
production of nuclear-generated electricity, while
reducing the impacts associated with spent nuclear fuel
disposal and reducing proliferation risks. DOE envisions
changing the U.S. nuclear energy fuel cycle1 from an
This calculation uses regression (CLReg V1.0 computer code) and non-parametric statistical methods, as specified in References 1 and 12, to develop the critical limit for the 21 Pressurized Water Reactor (PWR) spent nuclear fuel (SNF) waste package (WP) in the proposed geologic repository at Yucca Mountain, Nevada. The critical limit is a limiting value of the effective neutron multiplication factor at which a WP configuration is considered potentially critical.
The Reactor and Fuel Cycle Technology Subcommittee was formed to respond to the charge—set forth in the charter of the BRC—to evaluate existing fuel cycle technologies and R&D programs in terms of multiple criteria.
The purpose of this calculation is to perform a parametric study to determine the effects of fission product leaching, assembly collapse, and iron oxide loss on the reactivity of a waste package (WP) containing mixed oxide (MOX) spent nuclear fuel (SNF). Previous calculations (CRWMS M&O 1998a) have shown that the criticality control features of the WP are adequate to prevent criticality of a flooded WP for all the enrichment/burnup pairs expected for the MOX SNF.
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.
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
This calculation file uses the MCNP neutron transport code to determine the range of parameters for Pressurized Water Reactor Spent Nuclear Fuel contained with a 21 PWR waste package (WP). Four base geometry patterns were considered in this work and included the following: intact fuel assemblies with intact WP internal components, intact fuel assemblies with degraded WP internal components, degraded fuel assemblies with intact WP internal components, and degraded fuel assemblies with degraded WP internal components.
The American Nuclear Society (ANS) supports the safe, controlled, licensed, and regulated interim
storage of used nuclear fuel (UNF) (irradiated, spent fuel from a nuclear power reactor) until disposition
can be determined and completed. ANS supports the U.S. Nuclear Regulatory Commission’s (NRC’s)
determination that “spent fuel generated in any reactor can be stored safely and without significant
environmental impacts for at least 30 years beyond the licensed life for operation.
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.
After more than 20 years of commercial nuclear power, the Federal Government has yet to develop a broadly supported policy for fulfilling its legal responsibility for the final isolation of high-level radioactive waste. OTA's study concludes that until such a policy is adopted in law, there is a substantial risk that the false starts, shifts of policy, and fluctuating support that have plagued the final isolation program in the past will continue.
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.
The purpose of this report, and the information contained in the associated computerized data bases, is to establish the DOE/OCRWM reference characteristics of the radioactive waste materials that may be accepted by DOE for emplacement in the mined geologic disposal system as developed under the Nuclear Waste Policy Act of 1982. This report provides relevant technical data for use by DOE and its supporting contractors and is not intended to be a policy document.
The objective of this calculation is to document the Grand Gulf Unit 1 (GG1) 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 Nuclear Waste Policy Act of 1982, as amended, established a statutory basis
for managing the nation’s civilian (or commercially produced) spent nuclear
fuel. The law established a process for siting, developing, licensing, and constructing
an underground repository for the permanent disposal of that waste.
Utilities were given the primary responsibility for storing spent fuel until it is
accepted by the Department of Energy (DOE) for disposal at a repository —
originally expected to begin operating in 1998. Since then, however, the repository
In the November 1989 Report to Congress on Reassessment of the Civilian
Radioactive Waste Management Program (DOE/RW-0247), the Secretary of Energy
announced an initiative for developing a monitored retrievable storage (MRS) facility
that is to start spent-fuel acceptance in 1998. This facility, which will be licensed by
the U.S. Nuclear Regulatory Commission (NRC), will receive spent fuel from
commercial nuclear power plants and provide a limited amount of storage for this