Repository Criticality Control with Depleted-Uranium-Dioxide Cermet Waste Packages

Conference · Wed Nov 14 00:00:00 EST 2001

OSTI ID:788682

Forsberg, Charles W. ^[1]

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1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

It is proposed that the structural components and internal basket structures of waste packages (WPs) be constructed of depleted uranium dioxide (DUO₂)-steel cermets. The cermet contains DUO₂ imbedded in a steel matrix. The WPs are filled with spent nuclear fuel (SNF) and placed 2 in a geological repository. The WP provides a handling container for placement of SNF in the repository and is an engineered barrier to delay SNF degradation and subsequent release of radionuclides. SNF and other fissile wastes contain enriched uranium and transuranic fissile isotopes; thus, the potential for nuclear criticality exists. Most of the transuranic fissile isotopes, such as ²³⁹Pu, will have decayed to ²³³U or ²³⁵U before significant fissile-isotope migration from the degraded SNF or other fissile waste forms has occurred. Consequently, post-closure repository criticality issues are primarily from the fissile isotopes of uranium. As the WP degrades, the ²³⁸U in the DUO₂-steel cermet would mix with the degrading SNF and isotopically dilute ²³³U and ²³⁵U to levels that would ensure that post-closure criticality would not occur.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 788682
• Report Number(s): P01-111254; TRN: US0200553
• Resource Relation: Conference: 2001 ANS Winter Meeting Embedded Topical Meeting on Practical Implementation of Nuclear Criticality Safety, Reno, NV (United States), 11-15 Nov 2001; Other Information: PBD: 12 Jul 2001
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
CERMETS
CRITICALITY
DEPLETED URANIUM
ENRICHED URANIUM
SPENT FUELS
RADIOISOTOPES
URANIUM DIOXIDE
WASTE FORMS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE FACILITIES
SAFETY ANALYSIS
Nuclear Criticality Safety Program (NCSP)
Waste Packages (WPs)
Spent Nuclear Fuel (SNF)
Light-Water Reactor (LWR)
U.S. Nuclear Regulatory Commission (NRC)
Pressurized-Water Reactor (PWR)
Isotopic Dilution
Cermet