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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
K. Ashibea, H. Yoshida, Y. Naruse, C. R. Walthers, J. L. Anderson
Fusion Science and Technology | Volume 14 | Number 2 | September 1988 | Pages 546-551
Tritium Processing | Proceedings of the Third Topical Meeting on Tritium Technology in Fission, Fusion and Isotopic Applications (Toronto, Ontario, Canada, May 1-6, 1988) | doi.org/10.13182/FST88-A25190
Articles are hosted by Taylor and Francis Online.
A Monte Carlo computer code for analyzing free molecular gas flow has been developed to study the pumping characteristics of compound cryopumps for plasma chamber evacuation of fusion reactors. The code can deal with complex internal geometries of the pumps which commonly consist of cryopumping surfaces surrounded with elements like baffles, shields, and reservoirs. This code was used to study the pumping performance of a compound cryopump in the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. The results show that the calculated pumping speeds are strongly affected by the geometrical models employed in the calculations, and that an analysis based on a detailed model is essential to estimate the performance of compound cryopumps. The TSTA pumps were recently updated and are expected to be tested and operated with actual mixtures of deuterium, tritium, and helium. Then the code will be used to interpret the measured pumping speeds.aPermanent address: R&D Center, Toshiba Corporation, 4–1, Ukishima-cho, Kawasaki-ku, Kawasaki, 210, Japan, (044) 277–3111.