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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
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.
