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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Apr 2025
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Nuclear Science and Engineering
May 2025
Nuclear Technology
Fusion Science and Technology
Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Somayajulu L. N. Dhulipala, Chandrakanth Bolisetti, Richard Yorg, Philip Hashimoto, Justin L. Coleman, Mark Cox
Nuclear Technology | Volume 207 | Number 11 | November 2021 | Pages 1712-1724
Technical Note – Special section on the Seismic Analysis and Risk Assessment of Nuclear Facilities | doi.org/10.1080/00295450.2020.1792743
Articles are hosted by Taylor and Francis Online.
Following U.S. Department of Energy Order 420.1 C for the mitigation of natural phenomena hazards, such as earthquakes, to nuclear facilities through periodic reassessments, Idaho National Laboratory (INL) has developed the Seismic Hazard Periodic Re-Evaluation Methodology (SHPRM). The SHPRM involves seven criteria that evaluate changes to the seismic hazard at a site due to changes in the input models/data over time. Should these changes to the seismic hazard result in an increase in the design or licensing-basis ground motion of the facility from that which the facility was designed for, the SHPRM includes a criterion for reevaluating the facility risk objectives. While the criteria corresponding to the reevaluation of the seismic hazard and the design basis have been previously demonstrated and published, there is currently no guidance on reevaluating seismic risk for the purpose of SHPRM. This paper complements the published reports and papers on the application of SHPRM by demonstrating the risk objectives criterion for a generic nuclear facility (GNF), thereby closing the loop on the application of the SHPRM. The GNF is assumed to be located at the INL site and designated as a Seismic Design Category-3 facility as per American Society of Civil Engineers (ASCE)/Structural Engineering Institute (SEI) 43-05. The demonstration includes a risk assessment for a baseline seismic hazard calculated in 2006 and an updated seismic hazard calculated in 2015. After presenting the baseline and the updated seismic hazard curves at this site, the state-of-practice methodology for calculating fragility functions for the facility is presented, along with the fragilities calculated for the GNF. Employing a fault tree analysis using the INL in-house seismic analysis and risk assessment software MASTODON, the seismic risks of collapse of the GNF for the baseline and updated seismic hazards are computed to be 5.27E−05 and 5.2E−06, respectively. The results show that not only the reevaluated seismic risk is smaller, but more importantly, that it meets the risk objectives set by ASCE/SEI 43-05.
