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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
J. M. Cano, R. Caro, J. M. Martnez-Val
Nuclear Technology | Volume 48 | Number 3 | May 1980 | Pages 251-260
Technical Paper | Fuel Cycle | doi.org/10.13182/NT80-A32471
Articles are hosted by Taylor and Francis Online.
A nuclear fuel storage pool has to be designed to ensure subcriticality under any conditions. Within this framework, a peculiar moderation phenomenon that yields supercritical states from accidental (though very unlikely) circumstances is analyzed. Namely, in an overmoderated spent fuel pool, a reduction in the water density can lead to an increase in reactivity. Equally, a dry storage might be accidentally filled with water mist or foam, leading to a critical state. A numerical assessment is presented to point out the phenomenon and to clarify it. The dependence of results upon calculation methodologies and assumptions is also analyzed. The conclusion is reached that current methods with a slightly large number of energy groups should be used in this task. It is also found that poisoning the storage with a strong neutron absorber should avoid the aforementioned super-criticality.