This report is part of a report series designed to document benchmark-quality radiochemical assay data
against which computer code predictions of isotopic composition for spent nuclear fuel can be validated
to establish the uncertainty and bias associated with the code predictions. The experimental data analyzed
in the present report were acquired from two international programs: (1) ARIANE and (2) REBUS, both
coordinated by Belgonucleaire. All measurements include extensive actinide and fission product data of

NRC initiated a research activity with the Center for Nuclear Waste Regulatory Analyses (CNWRA®) to develop a conceptual test plan for measuring the quantity of residual water remaining in a canister following vacuum drying to the criterion referenced in NUREG–1536 (NRC, 2010). The test plan will be used to help NRC assess options for independently performing an experimental program or to support engagements with industry or the Department of Energy should they undertake a similar effort.

Taking credit for the reduced reactivity of spent nuclear fuel (SNF) in criticality analyses is referred to as burnup credit (BUC). Criticality safety evaluations require validation of the computational methods with critical experiments that are as similar as possible to the safety analysis models, and for which the keff values are known. This poses a challenge for validation of BUC criticality analyses, as critical experiments with actinide and fission product (FP)

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,

About 20,000 metric tons of spent, or used, nuclear
fuel have accumulated since the beginning of commercial
nuclear power prbduction in the United States. At the end
of the currently licensed period of all existing nuclear power
plants and those under construction, the amount of spent
nuclear fuel is expected to total 87,000 metric tons.
Thus far, practically all of the spent nuclear fuel is
stored in water-filled pools at reactor sites. However, space
does not exist in the pools to store all the spent fuel expected

Burnup credit (BUC) is a concept applied in the criticality safety analysis of spent nuclear fuel
in which credit or partial credit is taken for the reduced reactivity worth of the fuel due to both fissile
depletion and the buildup of actinides and fission products that act as net neutron absorbers.
Typically, a two-step process is applied in BUC analysis: first, depletion calculations are performed
to estimate the isotopic content of spent fuel based on its burnup history; second, three-dimensional

The Total System Model (TSM) is a planning tool that estimates the logistic and cost impacts of
various operational assumptions in accepting radioactive wastes. Waste forms currently tracked
are Commercial Spent Nuclear Fuel (CSNF), U.S. Department of Energy (DOE) spent nuclear
fuel (DOE SNF), and defense high-level (radioactive) waste (HLW). The TSM uses a TSM
Preprocessor (TSMPP) to generate the cask loads and target dates for shipments from waste
sites. The TSM then tracks these wastes from pickup at the waste sites until repository

The comparison of different nuclear fuel cycle options has become an integral element to any analysis of the future prospects for nuclear energy, in the United States and around the world. Concerns for supply security and price volatility of fossil fuels, combined with growing resolve to reduce the emissions of greenhouse gases, have caused a general shift in attitudes towards nuclear energy. However, there are lingering sustainability concerns for nuclear energy – long term uranium supply and environmental impact – as well as concerns about the proliferation of nuclear weapons.

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.