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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Eric Sykes (NWMO), Stefano D. Normani (Univ of Waterloo), Lorrie Fava, Darren Janeczek (MIRARCO)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 859-866
The ability to conceptualize and represent uncertainty in the geometry, dimensionality, and parameterization of key geosphere processes is a necessary element in the development of credible geosphere models. In crystalline rock typical of the Canadian Shield, these three-dimensional geosphere models are principally composed of discrete fracture network models and numerical groundwater models, which when combined, form an integrated platform for the on-going synthesis of geosphere data.
Fracture network modelling involves using three-dimensional, geostatistical tools for creating realistic, structurally possible models of fracture zone networks within a geosphere that are based on field data. The fracture network models, by honouring and incorporating available site data, allow for a greater understanding of the geometry and interconnectivity of the fractures in a quantitative manner. MoFrac, based upon the legacy fracture network modelling software FXSIM3D, is a new fracture network modelling tool capable of generating fracture network geometry composed of both stochastic and deterministic features.
The groundwater modelling methodologies applied within this project were developed and tested within the NWMO Geoscience Technical R&D program, and provide a numerical framework to assemble and integrate geosphere data including topography, surface water features, fracture networks, and hydraulic conductivities. These geosphere data, when synthesized into a three-dimensional geosphere conceptual model, form the basis for the integrated groundwater systems models. These models provide a quantitative assessment of suitability and facilitate a full understanding of the influences of geosphere factors such as topography, surface water features, and fracture zone geometry and interconnectedness. The numerical groundwater modelling software HGS was employed for this study.
A representative sub-regional scale test case based upon Canadian Shield data was used in order to demonstrate the modelling workflow. Performance measures include groundwater heads, velocity magnitudes, Mean Life Expectancies (MLEs), and depth of recharge of a surficial tracer.
