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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Take steps on SNF and HLW disposal
Matt Bowen
With a new administration and Congress, it is time once again to ponder what will happen—if anything—on U.S. spent nuclear fuel and high-level waste management policy over the next few years. One element of the forthcoming discussion seems clear: The executive and legislative branches are eager to talk about recycling commercial SNF. Whatever the merits of doing so, it does not obviate the need for one or more facilities for disposal of remaining long-lived radionuclides. For that reason, making progress on U.S. disposal capabilities remains urgent, lest the associated radionuclide inventories simply be left for future generations to deal with.
In March, Rick Perry, who was secretary of energy during President Trump’s first administration, observed that during his tenure at the Department of Energy it became clear to him that any plan to move SNF “required some practical consent of the receiving state and local community.”1
J. A. Favorite, W. M. Stacey, Jr.
Nuclear Science and Engineering | Volume 126 | Number 3 | July 1997 | Pages 282-292
Technical Paper | doi.org/10.13182/NSE97-A24481
Articles are hosted by Taylor and Francis Online.
A new variational estimate for dynamic reactivity that accounts for delayed neutron holdback is introduced and adapted for use with the improved quasistatic (IQS) method. Numerical tests on a large light water reactor model indicate that the computational effort required with the IQS method can be reduced by a factor of 3 to 4 by using this new variational estimate of dynamic reactivity. With comparable computational effort, the accuracy of the standard IQS method, which uses the flux shape interpolation/recomputation procedure and a first-order estimate of static reactivity, can be improved by using a standard variational estimate without the flux shape interpolation/recomputation procedure, and it can be further improved by using the new variational estimate of dynamic reactivity.
