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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.
Zhonglu Wang, Stephen F. Kry, Rebecca M. Howell, Mohammad Salehpour
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 610-614
Neutron Measurements | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9277
Articles are hosted by Taylor and Francis Online.
The neutron spectra and ambient dose equivalent were determined by unfolding measured Bonner sphere system data using different unfolding methods. These methods included a maximum entropy method (MAXED code), nonlinear least-squares method (GRAVEL code) with several different starting spectra, and a genetic algorithm method. These algorithms were used to unfold measured Bonner sphere data that had been collected using a LiI(Eu) detector and activation foils. The Bonner sphere system was exposed to neutrons from a known AmBe source and at the proton accelerator facility at the University of Texas M. D. Anderson Cancer Center. The total fluence rates and total ambient dose equivalents of the neutron field agree within 7.5%, regardless of unfolding algorithm or starting spectrum. In contrast, the fluence-weighted average energy varied dramatically, depending on the starting spectrum used in the unfolding process. These findings offer insight and guidance into the use of unfolding algorithms and starting spectra for neutron spectroscopy.