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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.”
Rainer Senger, Bill Lanyon, Paul Marschall, Stratis Vomvoris, Ai Fujiwara
Nuclear Technology | Volume 164 | Number 2 | November 2008 | Pages 155-168
Technical Paper | Tough206 | doi.org/10.13182/NT08-A4016
Articles are hosted by Taylor and Francis Online.
The Gas Migration Test (GMT) at the Grimsel Test Site underground laboratory in central Switzerland was designed to investigate gas migration through an engineered barrier system (EBS). The EBS consists of a concrete silo embedded in a sand/bentonite buffer emplaced in a silo cavern that intersects a shear zone in the surrounding granite host rock. The experiment was performed in a series of stages: (a) excavation of the access drift and silo cavern, (b) construction and instrumentation, (c) saturation of the EBS, (d) water tests, (e) long-term gas injection at different rates, (f) postgas water testing, (g) gas injection with a "cocktail" of gas tracers, and (h) depressurization and dismantling. A numerical model was developed for the design and analysis of the different stages and to describe the relevant phenomena associated with gas migration from a potential repository for transuranic waste.A numerical model of the GMT was implemented with the two-phase-flow code TOUGH2, representing the GMT silo with a multilayered radially symmetric mesh and the surrounding water-conducting granite shear zone with a two-dimensional vertical feature. The different stages of the experiment were simulated in sequence using the results of the previous stage as initial conditions for the subsequent stage. Two-phase-flow parameters for the EBS were derived from laboratory experiments on core samples of the different materials that comprise the EBS, while hydraulic properties of the sand/bentonite and of relevant interface zones were calibrated to the pressure responses in the silo and selected piezometers in the sand/bentonite. The results of the numerical modeling of the GMT experiment show that the main features and processes of the different stages of the experiment could be reasonably well reproduced. Following the initial calibration of effective properties from the water test response during stage 4, property changes during the subsequent test phase were calibrated as stress- or pressure-dependent permeability changes. During the gas injection phases, the pressure-dependent permeability change could be related to the minimum effective stresses along interfaces. The inferred coupled hydromechanical phenomena were implemented using pressure-dependent permeability relationships on interfaces at the top of the silo and between the sand/bentonite and the granite host rock. During the recovery sequence following the first injection gas phase, the calibrated decrease in permeability of the sand/bentonite above the silo was related to the pressure decline in the upper cavern, but there was no apparent stress change. However, the calibrated permeability reduction in the sand/bentonite was in the range of values measured during the EBS excavation. In addition, time-dependent permeability relationships were calibrated for the tunnel seal to account for the gradual decrease in water inflow from the upper cavern into the access tunnel and the drift.
