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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.”
Bernard Rottner
Nuclear Science and Engineering | Volume 155 | Number 3 | March 2007 | Pages 463-474
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2677
Articles are hosted by Taylor and Francis Online.
The activity of a radioactive waste package is usually evaluated from gamma measurements associated with transfer functions. These functions are calculated assuming that both activity and mass distributions are homogeneous. But, generally, activity and mass distributions are not homogeneous. This paper evaluates the effect of heterogeneities on the activity measurements on families of similar waste packages. An error arises, with a systematic part, leading to an overestimation or underestimation of the overall activity in a family of similar waste packages, and a stochastic part, whose mean effect on the overall activity of the family is null.In order to evaluate the effect of heterogeneities, numerical simulation of the filling of each package has been performed. Some filling parameters are randomly varied, according to the known characteristics of the real packages, so that the mass and activity distributions are different from one package to another but are always coherent with the characteristics of the real packages.These numerical simulations produce virtual families of packages. A way to fit and demonstrate the representativeness of the virtual family is described, so that the general results computed on this virtual family are applicable for the real family.
