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Nuclear Energy Conference & Expo (NECX)
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.
Toshiharu Muramatsu, Hisashi Ninokata
Nuclear Technology | Volume 97 | Number 2 | February 1992 | Pages 186-197
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34615
Articles are hosted by Taylor and Francis Online.
A three-dimensional in-vessel thermohydraulics analysis is carried out for the early phase of an unprotected transient overpower (UTOP) accident and delayed neutron precursor concentration transport in a typical loop-type fast breeder reactor plant. In the UTOP calculations, the time at which the sodium temperature reaches the reactor trip level is evaluated based on calculated upper plenum flow and temperature distributions. For fission product release from the core assemblies, the delayed neutron precursor concentration in the sodium that reaches the detectors depends on the location of the faulted assembly, threedimensional flow patterns, and hence, the residence time in the upper plenum. Delayed neutron precursors that bypassed the recirculation flow to appear in the plenum primarily contribute to the peak concentration.