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NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
Georgeta Radulescu, Ian C. Gauld, Germina Ilas, John C. Wagner
Nuclear Technology | Volume 188 | Number 2 | November 2014 | Pages 154-171
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT13-154
Articles are hosted by Taylor and Francis Online.
This paper describes a depletion code validation approach for criticality safety analysis using burnup credit for actinide and fission product nuclides in spent nuclear fuel (SNF) compositions. The technical basis for determining the uncertainties in the calculated nuclide concentrations is comparison of calculations to available measurements obtained from destructive radiochemical assay of SNF samples. Probability distributions developed for the uncertainties in the calculated nuclide concentrations were applied to the SNF compositions of criticality safety analysis models by the use of a Monte Carlo uncertainty sampling method to determine bias and bias uncertainty in the effective neutron multiplication factor. Application of the Monte Carlo uncertainty sampling approach is demonstrated for representative criticality safety analysis models of pressurized water reactor spent fuel pool storage racks and transportation packages using burnup-dependent nuclide concentrations calculated with Standardized Computer Analyses for Licensing Evaluation (SCALE) 6.1 and the Evaluated Nuclear Data File/B (ENDF/B) Version VII nuclear data. The validation approach and results support a recent revision of the U.S. Nuclear Regulatory Commission Interim Staff Guidance (ISG)-8.