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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Wright officially sworn in for third term at the NRC
The Nuclear Regulatory Commission recently announced that David Wright, after being nominated by President Trump and confirmed by the Senate, was ceremonially sworn in as NRC chair on September 8.
This swearing in comes more than a month after Wright began his third term on the commission; he began leading as chair July 31. His term will conclude on June 30, 2030.
John D. Bess
Nuclear Technology | Volume 177 | Number 1 | January 2012 | Pages 29-35
Technical Paper | Reactor Safety | doi.org/10.13182/NT12-A13325
Articles are hosted by Taylor and Francis Online.
A series of 15 critical experiments performed at the Rocky Flats Critical Mass Laboratory in the late 1960s was evaluated and then determined to represent acceptable benchmark experiments for the validation of calculational methods. This series of experiments was part of a larger set of experiments performed to evaluate operational safety margins at the Rocky Flats Plant. The experiments consisted of bare plutonium metal hemishells reflected by steel hemishells of increasing thickness and motor oil. The hemishell assembly was suspended within dual aluminum tanks. Criticality was achieved by pumping oil into the tanks such that effectively infinite reflection was achieved in all directions except directly above the assembly; then the critical oil height was recorded. The results of these experiments had been initially ignored because early computational methods had been inadequate to analyze partially reflected configurations. The dominant uncertainties include the uncertainty in the average plutonium density and the composition of materials in the gaps between the plutonium hemishells. Simple and detailed benchmark models were developed. Eigenvalue calculations using MCNP5 and ENDF/B-VII.0 were within 2 of the benchmark values. This benchmark evaluation has been added to the International Handbook of Evaluated Criticality Safety Benchmark Experiments.