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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.
Noriyoshi Nakanishi, Takashi Shikata, Shin Fujita, Toshiso Kosako
Nuclear Technology | Volume 112 | Number 1 | October 1995 | Pages 132-141
Technical Paper | Radiation Protection | doi.org/10.13182/NT95-A15858
Articles are hosted by Taylor and Francis Online.
Shielding characteristics of iron, lead, ordinary concrete, heavy concrete, graphite, marble, water, and paraffin were calculated for monoenergetic source neutrons with energies <400MeV. The depth dependence of neutron and secondary photon transmitted dose equivalents at the exit surfaces of shields of varying thickness is exhibited for some monoenergetic source neutrons and for each material. Their shielding characteristics are compared and discussed in terms of the degradation process of neutron energy and the change of neutron spectrum in typical shielding materials. Calculations were carried out by using the one-dimensional discrete ordinates code ANISN-JR and the cross-section library DLC-87/HILO. Systematic knowledge concerning the shielding of neutrons with energies <400 MeV was successfully obtained.