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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.
Ahmet Bozkurt, Nicholas Tsoulfanidis
Nuclear Technology | Volume 119 | Number 1 | July 1997 | Pages 38-47
Technical Paper | Radiation Protection | doi.org/10.13182/NT77-A35393
Articles are hosted by Taylor and Francis Online.
Gamma-ray dose rate distribution around a pressurized water reactor spent-fuel assembly is studied using the Monte Carlo N-particle transport code (MCNP) version 4a. A detailed rod-by-rod modeling of the assembly is utilized, showing explicitly the fuel, cladding, control rod channels, and the instrumentation tube. A cylindrically distributed source of gamma rays, within every fuel rod, is considered with a seven-group energy spectrum. Dose rates are obtained by tallying the gamma rays at several axial and radial positions outside the assembly. The results indicate that the radial distribution of the dose rate can be represented by a power relationship of the form r−n, where r is the radial distance from the assembly center. Another important conclusion from this study is that the dose rate close to the assembly surface is overestimated if a homogeneous assembly model is used.