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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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).”
George C. Fullmer
Nuclear Technology | Volume 57 | Number 1 | April 1982 | Pages 58-64
Technical Paper | Fuel Cycle | doi.org/10.13182/NT82-A16186
Articles are hosted by Taylor and Francis Online.
The refueling of a nuclear power reactor, involving opening of the pressure vessel and associated plant maintenance, is characteristically planned to occur at a frequency on the order of a year or longer. The length of a boiling water reactor (BWR) operating cycle, the time between successive refueling shutdowns, may be extended several weeks to several months beyond normal “reactivity life” with proper planning. Reactivity for extended operation is available through the use of the negative moderator and fuel reactivity coefficient effects—especially the BWR void coefficient. The coastdown power reduction mode has been applied in 70% of recent cycles. Increased core flow and feedwater temperature reduction have also been used for cycle extension and to enhance operating maneuverability.