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Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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.”
Martin Victor Polley
Nuclear Technology | Volume 71 | Number 3 | December 1985 | Pages 557-567
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A33678
Articles are hosted by Taylor and Francis Online.
It is widely experienced that operation with a low primary coolant pHT leads to heavy deposition on fuel-pin cladding in pressurized water reactors (PWRs). This is thought to be due principally to solubilities of corrosion products exhibiting negative temperature dependencies at low coolant pHT, leading to precipitation from the solution onto core surfaces. Solubilities also increase at low pHT values and this may be an additional reason for the increased deposition. Particulate deposition may also depend on coolant pHT. Operation at low coolant pHT may thus cause increased corrosion product activity transport, leading to higher dose rates around the primary circuit. The possible correlation between low pHT operation and steam generator channel head dose rates was investigated, using detailed data from nine Westinghouse PWRs. The coolant chemistry was quantified by calculating both the percentage of operating time at low pHT and a numerical “precipitation index” in order to establish the extent of operation below that coolant pHT above which little core crud deposition is expected. Time averaged pH’s were also calculated for each cycle. End-of-cycle dose rates were plotted against these coolant chemistry parameters on a plantby-plant basis and statistical tests were applied following linear regression analysis. Positive correlations were obtained and it was found that, for the limited number of plants in the survey, these correlations were between the categories “significant” and “probably significant” for cycle 1 and cycle 2 data.