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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.”
S. B. Kim, S. L. Chouhan, P. A. Davis
Fusion Science and Technology | Volume 60 | Number 3 | October 2011 | Pages 960-963
Measurement, Monitoring, and Accountancy | Proceedings of the Ninth International Conference on Tritium Science and Technology | doi.org/10.13182/FST11-A12575
Articles are hosted by Taylor and Francis Online.
The high mobility of tritium as HTO implies that, under steady-state conditions, the T/H ratio (or equivalently the HTO concentration) is the same in all water compartments of the environment. This is the basis of the specific activity (SA) model, which underlies almost all environmental tritium models. SA concepts apply to organically bound tritium (OBT) as well, since the OBT formed by a given plant process at a given time has a T/H ratio that reflects the ratio in the water that enters into that process. There is no empirical evidence that the bioaccumulation of tritium in aquatic and wetland plants will occur. OBT/HTO ratios less than one is consistently found in the laboratory where the HTO concentrations to which the plants are exposed can be held constant. These data suggest a value of 0.7 for the OBT/HTO ratio under equilibrium conditions in the laboratory. Theoretical considerations suggest that the value of the OBT/HTO ratio in plants is significantly different from one and, in most cases, greater than one. This is primarily due to the much longer residence time of OBT in plants as compared to HTO. The observed HTO concentrations are much higher than OBT concentrations, which makes OBT/HTO ratio smaller than unit in contrast with SA based expectations. In addition to this, the IMPACT model overpredicted HTO and OBT concentrations in plants and animals by a factor of 3 or 4, on average. This work is summary of the AECL funded research project (1).