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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
Rob P. Rechard
Nuclear Technology | Volume 190 | Number 2 | May 2015 | Pages 97-126
Technical Paper | Reactor Safety | doi.org/10.13182/NT14-40
Articles are hosted by Taylor and Francis Online.
This paper, Part I of two companion papers, reviews concepts underlying the basis for evaluating the criticality scenario for an assessment of performance after closure of a geologic repository for radioactive waste. In the United States, either a low-probability or low-consequence rationale can be the basis of excluding criticality, using the usual assumptions that (a) the interplay between the probability and consequence is not significant and (b) the mean of the epistemic uncertainty of the probability and consequence provides a sufficient approximation. Furthermore, the rationale can be based on either qualitative or quantitative arguments. For those situations with quantitative arguments, this paper provides additional perspective on evaluating the criticality scenario by combining quantitative estimates of low probability and low consequence as a complementary cumulative distribution function. As a demonstration, the low probability and low consequence of the criticality scenario for the Waste Isolation Pilot Plant (a repository for defense transuranic element waste) is presented.