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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.
Toshihiko Ohnuki, Tadao Tanaka, Hiromichi Ogawa, Tadatoshi Yamamoto
Nuclear Technology | Volume 88 | Number 1 | October 1989 | Pages 55-63
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT89-A34336
Articles are hosted by Taylor and Francis Online.
The relationship of the retardation factor of a radionuclide for undisturbed soil and that for disturbed soil has been investigated. The migration model is based on the assumption that both reactive (dynamic) and nonreactive (stagnant) sites exist in the soil column. The retardation factor for undisturbed soil is represented by the following equation:Rfu = Su/SdRfd ,where Rfu and Rfd are retardation factors for undisturbed and disturbed soil, respectively, and Su and Sd are degrees of water saturation in undisturbed and disturbed soils, respectively. The migration experiments for both the undisturbed and disturbed soil columns were carried out using 85Sr. The average retardation factor for the undisturbed soil is smaller than that for disturbed soil, and the degree of water saturation in the undisturbed soil column is smaller than that in the disturbed soil column. The retardation factor for the undisturbed soil estimated, based on the above equation, is approximately the same as the measured retardation factor for the undisturbed soil.
