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2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
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Oklo’s Isotope Test Reactor achieves criticality
Oklo’s Groves Isotope Test Reactor became the fifth Department of Energy–authorized reactor to achieve criticality under the agency’s authorization process, it was announced earlier today.
Criticality was reached at 9:19 p.m. (EDT) on Wednesday at the company’s Groves facility in Lockhart, Texas, according to the DOE.
Technical Session|Sponsored by NCSD
Wednesday, June 18, 2025|3:15–5:00PM CDT|Armitage
Session Chair:
Natalie Cannon
Alternate Chair:
Benjamin Martin
Session Organizer:
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Verified, Archived Library of Inputs and Data (VALID) Online Repository
3:15–3:35PM CDT
Travis M. Greene (ORNL), Robert A. Lefebvre (ORNL)
Paper
Criticality Safety Nuclide Rankings for TRISO Spent Fuel Applications
3:35–3:55PM CDT
Alex Shaw (ORNL), Veronica V. Karriem (ORNL), Walid A. Metwally (ORNL)
Microreactor Assembly Transportation Cask Model for Criticality Safety Basis Assessment
3:55–4:15PM CDT
Zhaopeng Zhong (ANL), Ahmed Amin Abdelhameed (ANL), Nicolas E. Stauff (ANL), Cihangir Celik (ORNL)
A New Benchmark Evaluation of Historical Experiments with HEU Cylinders and Annuli with 10-Inch Graphite Reflectors
4:15–4:35PM CDT
Kathryn Worrell (Univ. Tennessee, Knoxville), Vladimir Sobes (Univ. Tennessee, Knoxville), William J. Marshall (ORNL)
Criticality Evaluations of Additional Neutron Absorber for LEU+ ATF in Fuel Storage Systems
4:35–4:55PM CDT
Keon il Cha (Sejong Univ.), Kyoon ho Cha (Sejong Univ.)