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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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.”
Paul E. Mariner (SNL)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 286-293
Humic complexation has the potential to increase actinide mobility and hamper waste isolation in geologic nuclear waste repositories. This study shows that humic complexation of tetravalent actinides (Th(IV), U(IV), Np(IV), and Pu(IV)) has been overestimated in past performance assessments of the Waste Isolation Pilot Plant (WIPP). Major reductions are needed for PHUMSIM and PHUMCIM, the equilibrium concentration ratios of humic-bound aqueous actinide to non-colloidal aqueous actinide. These coefficients are currently set at a value of 6.3 based on Th(IV) measurements in particle size fractions of seawater. Actual humic partitioning is expected to be significantly lower in WIPP brines primarily because pH is higher (~9) and concentrations of competing cations (e.g., Mg2+) are higher. In this work, data from recent studies of Th(IV)-humic, U(IV)-humic, and Ca2+-humic complexation are used to simulate competitive humic complexation under WIPP repository conditions and to estimate new An(IV) PHUMSIM and PHUMCIM values. The new lower coefficients reduce the humic-bound An(IV) concentrations by more than 99%, causing a reduction in total mobile An(IV) concentrations by 85% to 86%, assuming no other type of An(IV) colloid (i.e., intrinsic, microbial, and mineral fragment colloids) is present in significant concentrations.
