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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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No impact from Savannah River radioactive wasps
The news is abuzz with recent news stories about four radioactive wasp nests found at the Department of Energy’s Savannah River Site in South Carolina. The site has been undergoing cleanup operations since the 1990s related to the production of plutonium and tritium for defense purposes during the Cold War. Cleanup activities are expected to continue into the 2060s.
T. J. Downar, J. A. Stillman
Nuclear Science and Engineering | Volume 94 | Number 3 | November 1986 | Pages 241-250
Technical Paper | doi.org/10.13182/NSE86-A17267
Articles are hosted by Taylor and Francis Online.
A model is developed to generate homogenized, two-group cross-section data for pressurized water reactor (PWR) fuel assemblies loaded with burnable absorbers by explicitly incorporating the effects of the neutron poison into the unpoisoned group constants. This provides the calculational freedom to use the assembly burnable absorber loading as an independent variable in dynamic search methods for optimizing low-leakage PWR core reloads. To achieve an accuracy of better than 0.2% in the assembly k∞, separate consideration is given to the absorption and scattering perturbations, as well as to the spectrum-hardening effects caused by the presence of burnable absorbers in the assembly. The model was validated first by comparison of unit assembly cross sections to data from reference calculations and then by use of the model in the Electric Power Research Institute nodal code SIMULATE-E and comparison to reference core power distributions.