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

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

The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for all spent fuels and high-level wastes (HLW) that will eventually be disposed of in a geologic repository. The purpose of this document, and the information contained in the associated computerized data bases and supporting technical reports, is to provide the technical characteristics of the radioactive waste materials that will (or may) be accepted by DOE for interim storage in an MRS or emplacement in a repository as developed under the Nuclear Waste Policy Act Amendment of 1987.

This report presents the results of computer code benchmark simulations against spent fuel radiochemical assay
measurements from the Kansai Electric Ltd. Takahama-3 reactor published by the Japan Atomic Energy
Research Institute. Takahama-3 is a pressurized-water reactor that operates with a 17 × 17 fuel-assembly design.
Spent fuel samples were obtained from assemblies operated for 2 and 3 cycles and achieved a maximum burnup
of 47 GWd/MTU. Radiochemical analyses were performed on two rods having an initial enrichment of

The report describes the final results of the Phase IIIB Benchmark conducted by the
Expert Group on Burnup Credit Criticality Safety under the auspices of the Nuclear Energy
Agency (NEA) of the Organization for Economic Cooperation and Development (OECD).
The Benchmark was intended to compare the predictability of current computer code and
data library combinations for the atomic number densities of an irradiated BWR fuel
assembly model. The fuel assembly was irradiated under specific power of 25.6 MW/tHM

In January 1999, the U.S. Department of Energy (DOE)/Office of Civilian Radioactive
Waste Management (OCRWM) submitted the Disposal Criticality Analysis Methodology
Topical Report, Revision 0 (TR) to the U.S. Nuclear Regulatory Commission (NRC) for
review and approval. The TR presents an overall approach for consideration of postclosure
disposal criticality of commercial and defense high-level waste to be placed at
the proposed Yucca Mountain site. During the course of the review and interactions

This standard provides criteria for accounting for reactivity effects of fuel irradiation and radioactive decay in criticality safety control of storage, transportation, and disposal of commercial LWR UO2 fuel assemblies.

This standard assumes the fuel and any fixed burnable absorbers are contained in an intact assembly. Additional considerations could be necessary for fuel assemblies that have been disassembled, consolidated, damaged, or reconfigured in any manner.

The Interim Staff Guidance on burnup credit (ISG-8) for spent fuel in storage and transportation casks, issued by the Nuclear Regulatory Commission’s Spent Fuel Project Office, recommends a burnup measurement for each assembly to confirm the reactor record and compliance with the assembly burnup value used for loading acceptance. This recommendation is intended to prevent unauthorized loading (misloading) of assemblies due to inaccuracies in reactor burnup records and/or improper assembly identification, thereby ensuring that the appropriate subcritical margin is maintained.

This report has been prepared by an ad-hoc Working Group (WG) formed by ANDRA (France), NUMO (Japan), NAGRA (Switzerland) and ENRESA (Spain) in May 2003, after the EDRAM meeting held in Valencia to study the situation in the different EDRAM member countries regarding the treatment of radioactive waste ownership and management of long-term liabilities.

Present regulatory practices provide as much burnup credit flexibility as can be currently
expected. Further progress is achievable by incorporating the negative reactivity effects of a
subset of neutron-absorbing fission-product isotopes, and by optimizing the procedural approach
for establishing the burnup characteristics of the spent fuel to be loaded in burnup-creditdesigned
storage and transportation systems. This report describes progress toward developing a

The Department of Energy (DOE), pursuant to the Atomic Energy Act of 1954
as amended, the Energy Reorganization Act of 1974, the Department of Energy
Organization Act of 1977, and the Nuclear Waste Policy Act of 1982 (the Act),
has the responsibility to provide for the disposal of high-level radioactive
waste and spent nuclear fuel.* The DOE selected mined geologic repositories
as the preferred means for the disposal of commercially generated high-level
radioactive waste and spent fuel (Federal Register, Vol. 46, p. 26677, May 14,

Pressurized water reactor (PWR) burnup credit validation is
demonstrated using the benchmarks for quantifying fuel reactivity
decrements, published as Benchmarks for Quantifying Fuel Reactivity
Depletion Uncertainty, Electric Power Research Institute (EPRI)
report 1022909. This demonstration uses the depletion module
TRITON (Transport Rigor Implemented with Time-Dependent
Operation for Neutronic Depletion) available in the SCALE 6.1
(Standardized Computer Analyses for Licensing Evaluations) code

This report is part of a report series designed to document benchmark-quality radiochemical isotopic
assay data against which computer code accuracy can be quantified to establish the uncertainty and bias
associated with the code predictions. The experimental data included in the report series were acquired
from domestic and international programs and include spent fuel samples that cover a large burnup range.
The measurements analyzed in the current report, for which experimental data is publicly available,

In 2007 the OECD Nuclear Energy Agency (NEA) Radioactive Waste Management Committee
(RWMC) launched a four-year project on the topics of reversibility and retrievability in geological
disposal. The goal of the project studies and activities (www.oecd-nea.org/rwm/rr) was to
acknowledge the range of approaches to reversibility and retrievability (R&R), rather than to
recommend a specific approach, and to provide a basis for reflection rather than to lead towards