The "Summary Report of SNF Isotopic Comparisons for the Disposal Criticality Analysis Methodology" contains a summary of the analyses that compare SNF measured isotopic concentrations (radiochemical assays) to calculated SNF isotop~c concentrations (SAS2H module ·orScale4.3). The results of these analyses are used to support the validation of the isotopic models for spent commercial light water reactor (LWR) fuel.

Thirty spent fuel samples obtained from boiling-water-reactor (BWR) fuel pins have been
modeled at Oak Ridge National Laboratory using the SAS2H sequence of the SCALE code system.
The SAS2H sequence uses transport methods combined with the depletion and decay capabilities
of the ORIGEN-S code to estimate the isotopic composition of fuel as a function of its burnup
history. Results of these calculations are compared with chemical assay measurements of spent fuel
inventories for each sample. Results show reasonable agreement between measured and predicted

Isotopic characterization of spent fuel via depletion and decay calculations is necessary for
determination of source terms for subsequent system analyses involving heat transfer, radiation
shielding, isotopic migration, etc. Unlike fresh fuel assumptions typically employed in the criticality
safety analysis of spent fuel configurations, burnup credit applications also rely on depletion and
decay calculations to predict the isotopic composition of spent fuel. These isotopics are used in

Slides - WM2014 Symposia, March 2-6, 2014, Phoenix, AZ

The Used Fuel Disposition (UFD) Transportation Task commenced in October 2010. As its first task, Pacific Northwest National Laboratory (PNNL) compiled a list of structures, systems, and components (SSCs) of transportation systems and their possible degradation mechanisms during extended storage. The list of SSCs and the associated degradation mechanisms [known as features, events, and processes (FEPs)] were based on the list of used nuclear fuel (UNF) storage system SSCs and degradation mechanisms developed by the UFD Storage Task (Hanson et al. 2011).

This test protocols report presents the NRC staff’s preliminary plans for an experimental phase of the Package Performance Study (PPS), which is examining the response of transportation casks to extreme transportation accident conditions. The staff proposes to conduct tests of full-scale rail and full-scale truck casks including a high-speed impact with an unyielding surface followed by an extreme fire test. The NRC has a contract in place with Sandia National Laboratories (SNL) to conduct the impact and fire tests and to carry out a series of analyses to support the test program.

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<p><span style="font-size: 12.000000pt; font-family: 'TimesNewRomanPSMT'">This report fulfills the M1 milestone M11UF041401, &ldquo;Storage R&amp;D Opportunities Report&rdquo; under Work Package Number FTPN11UF0414. </span></p>