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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.”
Xia Bing, Jiong Guo, Chunlin Wei, Ding She, Jian Zhang, Fu Li (Tsinghua Univ)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 848-852
The pebble bed high temperature reactors (PB-HTRs) are one of the promising reactor types for the next generation nuclear systems. Some intrinsic features of the PB-HTRs’ spherical fuel element embedded with the TRISO coated fuel particles bring high proliferation-resistance to the PB-HTR spent fuel storage, including the continuous on-line fueling strategy, the difficulty of processing TRISO particles, the low heavy metal density in the fuel pebbles and the high depletion of plutonium. The material accountancy concept and methodology of PB-HTR spent fuel storage are proposed in this work. For PB-HTRs, the spent fuel storage should be treated as an item facility; however, the items in PB-HTR spent fuel storage are the spent fuel containers, instead of the spent fuel assemblies in conventional PWR’s spent fuel storage. The accountancy of nuclear material should be implemented by evaluating the average burnup value of a batch of spent fuels. For the equilibrium core of PB-HTR, the average burnup value of a batch of spent fuel pebbles is determined by the integral power during the period when these pebbles are unloaded from the reactor core. Furthermore, the burnup value of each spent fuel pebble can also be measured by gamma spectroscopy upon the long-lived fission product 137Cs. After evaluating the spent fuel burnup, the dependency of the amounts of heavy metal nuclides upon the burnup value of a spent fuel pebble is estimated by the depletion calculations. It is revealed that the non-proliferation features of PB-HTR spent fuel storage is excellent and the accountancy methodology proposed in this work is feasible. Besides the high safety features, the high proliferation-resistance can be another attraction of the PB-HTRs.