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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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Nuclear Technology
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Latest News
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. G. B. Saccheri, N. E. Todreas, M. J. Driscoll
Nuclear Technology | Volume 158 | Number 3 | June 2007 | Pages 315-347
Technical Paper | Fission Reactors | doi.org/10.13182/NT07-A3845
Articles are hosted by Taylor and Francis Online.
An 8-yr core design for an epithermal, water-cooled reactor has been developed based upon assessments of nuclear reactor physics, thermal hydraulics, and economics. An integral-vessel configuration is adopted, and self-supporting wire-wrap fuel is employed for the tight lattice of the epithermal core. A streaming path is incorporated in each assembly to ensure a negative void coefficient. A whole-core simulation of the tight core with the stochastic, continuous-energy, transport code MCNP shows a negative void coefficient for the whole cycle during normal operating conditions. Analysis of in-core, flow-induced vibrations indicates that the design has a greater margin to fluid-elastic instability than a standard pressurized water reactor, allowing for higher coolant mass flux and improved safety. Enhanced flow mixing and thermal margins are also achieved, and the VIPRETM code for subchannel thermal-hydraulic analysis has been used to calculate the critical heat flux (CHF) by means of a wire-wrap CHF correlation specifically introduced in the source code. The combination of increased fuel enrichment (~14 wt% 235U, still below the proliferation-resistant limit of 20 wt% 235U), relatively low core-average discharge burnup (70 MWd/kg HM), and very long core life (8 yr) lead to high lifetime-levelized fuel cycle unit cost [in mills/kWh(electric)]. However, both operation and maintenance (O&M) and capital-related expenditures strongly benefit from the higher electric output per unit volume, which yields quite small lifetime-levelized capital and O&M unit costs for the overall plant. Financing requirements are included, and an estimate is provided for the lifetime-levelized total unit cost of the epithermal core, which is ~16% lower than that of a more open-lattice thermal spectrum core, fitting into the same core envelope and with a 4-yr lifetime.
