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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.
Kai Masuda, Toshiteru Kii, Hideaki Ohgaki, Heishun Zen, Tetsuo Yamazaki
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 467-471
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection | doi.org/10.13182/NT09-A9226
Articles are hosted by Taylor and Francis Online.
A shielding layout for a 40-MeV electron linac is presented. The linac building consists of 15-cm concrete roof and walls, and 2-m-thick shielding walls for horizontal shielding. No shielding roof covers the linac, which reduces the capital cost of the facility building. Though the present shielding layout allows an operation of up to 11.8-W averaged beam power, experimental dose equivalent rates are found to be much greater than that predicted by the skyshine formula. Monte Carlo (MCNP 4C) simulations indicate considerable contributions of radiation scattering by the thin roof and walls.
