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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.
P. S. W. Chan, A. R. Dastur
Nuclear Science and Engineering | Volume 103 | Number 3 | November 1989 | Pages 289-293
Technical Paper | doi.org/10.13182/NSE89-A23680
Articles are hosted by Taylor and Francis Online.
The sensitivity to the axial neutron flux distribution of the positive reactivity that may have been introduced on initiation of scram in Chernobyl-4 has been evaluated. It is found that the scram reactivity is positive and its size is remarkably insensitive to a wide range of axial flux distortion provided the flux shape is concave, which is a characteristic of neutronic decoupling of the core. In contrast, the scram reactivity is negative when flux shapes are convex, i.e., those that are a characteristic of strong neutronic coupling. This indicates that unless there were a significant number of control absorbers present in the core just before the accident to provide a convex flux shape, the chances that some positive scram reactivity was inserted to initiate the power pulse are high.