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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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Deep geologic repository progress—2025 Update
Editor's note: This article has was originally published in November 2023. It has been updated with new information as of June 2025.
Outside my office, there is a display case filled with rock samples from all over the world. It contains a disk of translucent, orange salt from the Waste Isolation Pilot Plant near Carlsbad, N.M.; a core of white-and-bronze gneiss from the site of the future deep geologic repository in Eurajoki, Finland; several angular chunks of fine-grained, gray claystone from the underground research laboratory at Bure, France; and a piece of coarse-grained granite from the underground research tunnel in Daejeon, South Korea.
Kazuya Ohgama, Hiroki Katagiri, Atsushi Takegoshi, Taira Hazama
Nuclear Technology | Volume 207 | Number 12 | December 2021 | Pages 1810-1820
Technical Paper | doi.org/10.1080/00295450.2020.1846481
Articles are hosted by Taylor and Francis Online.
In the prototype fast breeder reactor Monju, fixed absorber worth was measured as the difference of core reactivity measured by control rod worth between cores with and without a single fixed absorber or three fixed absorbers. In this paper, the measurements are evaluated in detail, and their reliability and usefulness as validation data are investigated through a comparison with calculations using the latest neutronics design methodology developed at Japan Atomic Energy Agency. Calculated-to-experiment values and their uncertainties of fixed absorber worth were 1.00 ± 0.05 and 1.02 ± 0.04, respectively. Through this study, the measurements and calculations were found consistent and reliable.
