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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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A webinar, and a new opportunity to take ANS’s CNP Exam
Applications are now open for the fall 2025 testing period for the American Nuclear Society’s Certified Nuclear Professional (CNP) exam. Applications are being accepted through October 14, and only three testing sessions are offered per year, so it is important to apply soon. The test will be administered from November 12 through December 16. To check eligibility and schedule your exam, click here.
In addition, taking place tomorrow (September 19) from 12:00 noon to 1:00 p.m. (CDT), ANS will host a new webinar, “How to Become a Certified Nuclear Professional.” More information is available below in this article.
Lee G. Glascoe, Thomas A. Buscheck, James Gansemer, Yunwei Sun, Kenrick Lee
Nuclear Technology | Volume 148 | Number 2 | November 2004 | Pages 125-137
Technical Paper | High-Level Radioactive Waste Disposal | doi.org/10.13182/NT04-A3553
Articles are hosted by Taylor and Francis Online.
The MultiScale ThermoHydrologic Model (MSTHM) is used to predict thermal-hydrologic conditions in emplacement drifts and the adjoining host rock throughout a proposed nuclear waste repository. This modeling effort simulates a lower-temperature operation mode with a different panel loading than the repository currently being considered for the Yucca Mountain license application. Simulations address the influence of repository-scale thermal-conductivity heterogeneity and the influence of preclosure operational factors on thermal-loading conditions. MSTHM can accommodate a complex repository layout, a development that, along with other improvements, enables more rigorous analyses of preclosure operational factors. Differences in MSTHM output occurring with these new capabilities are noted for a new sequential waste-package-loading technique compared with a standard simultaneous-loading technique. Alternative approaches to modeling repository-scale thermal-conductivity heterogeneity in the host-rock units are investigated, and a study incorporating geostatistically varied host-rock thermal conductivity is discussed.