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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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).”
Yoshitaka Naito, Kazuo Azekura
Nuclear Technology | Volume 204 | Number 1 | October 2018 | Pages 94-100
Technical Paper | doi.org/10.1080/00295450.2018.1469344
Articles are hosted by Taylor and Francis Online.
In this paper, a method is proposed to evaluate the extent of subcriticality of an accident-damaged nuclear reactor. With this method the activity ratio of two fission product (FP) rare gas nuclides and is measured. From the measured value, the value of the nuclides in the fuel region is estimated by correcting for the time lag incurred when the gases diffuse from the fuel region to the measuring point. A simple expression for an effective multiplication factor has been derived that uses the corrected -to- activity ratio and the -to- fission yield ratios of and but that does not require information on the amount or distribution of the fuel material, making the proposed method very simple. This method has the advantage that FP rare gases can easily leak from the reactor core through many openings and gaps, reaching germanium counters without reacting with other materials.