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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
John Avis, Nicola Calder (Geofirma Eng Ltd), Erik Kremer (NWMO)
Proceedings | 16th International High-Level Radioactive Waste Management Conference (IHLRWM 2017) | Charlotte, NC, April 9-13, 2017 | Pages 363-370
The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management, the federally-approved plan for the safe long-term management of Canada’s used nuclear fuel. Under this plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable host rock formation.
The NWMO completed an assessment of postclosure safety for a conceptual repository constructed at a depth of 500 m below ground surface (mBGS) in a hypothetical sedimentary rock setting in Southern Ontario, Canada. The Normal Evolution Scenario considered in that assessment postulates the release of radionuclides from defective containers and subsequent transport to the biosphere via a water supply well. Transport simulations were performed using constant climate conditions and a steady-state groundwater flow geosphere. Results indicate that doses from these postulated releases would be many orders of magnitude below the regulatory limit.
This paper presents results from a follow-up study which considers the impact of glaciation on transport, evaluating a large number of sensitivity cases for geosphere parameters, processes, and boundary conditions. Sensitivity cases are compared using transient system performance over a 1 million-year simulation period. A “snapshot” Mean Life Expectancy (MLE) approach is developed where MLE calculations are performed at 500-year intervals by assuming the flow system is constant at those times. MLE statistics from across the repository footprint are presented. Time-series results from minimum “snapshot” MLE calculations provide a useful data set for effective comparisons of temporal effects over the 1 million-year simulation period. Summary statistics provide useful comparisons of sensitivity cases.
