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The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
D. C. Hunt, Robert E. Rothe
Nuclear Science and Engineering | Volume 46 | Number 1 | October 1971 | Pages 76-87
Technical Paper | doi.org/10.13182/NSE71-A22337
Articles are hosted by Taylor and Francis Online.
The results of criticality measurements on enriched (93.16% 235U) uranium metal spheres symmetrically immersed in enriched (93.18% 235U) uranyl nitrate solution cylinders are reported. The solution cylinders are 26.5, 38.4, and 51.1 cm in diameter with heights ranging from 16 to 70 cm. Solution concentrations, expressed in grams of uranium per liter, are 11.47, 12.55, 13.12, 21.25, 24.20, 24.72, 103.0, and 104.8. Twenty-seven critical systems are identified. The experimental critical parameters of each system are compared with computed values obtained by transport (DTF) and Monte Carlo (KENO) methods. Results from neither, method exhibit a systematic difference from experimental values; the average difference in the critical radius is 2.5% for DTF and 2.0% for KENO. The effects of experimental perturbations are determined experimentally and calculationally.