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ANS Student Conference 2025
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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
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.