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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.
Sunil D. Weerakkody, Warren F. Witzig
Nuclear Technology | Volume 78 | Number 1 | July 1987 | Pages 43-53
Technical Paper | Nuclear Safety | doi.org/10.13182/NT87-A34007
Articles are hosted by Taylor and Francis Online.
A statistical decision theory provides a rational theoretical model that enables an algorithm to select appropriate off-site protective actions. Existing knowledge on safety system and containment event trees, the spectrum of release states, and statistical decision theory were used to develop a model that accommodates actual and potential radiation risks and nonradiological risks such as risks of evacuation in selecting off-site protective actions. The usefulness of the model developed is illustrated by applying it to the Three Mile Island Unit 2 (TMI-2) scenario and comparing the actual decisions made with the decisions provided by the model. Conclusions drawn by modeling the TMI-2 related data are in general agreement with off-site protective actions taken. Finally, the model is used to illustrate the extremely low likelihood of the occurrence of accident scenarios that require evacuations beyond a 3.2-km radius and to support a plume exposure pathway emergency planning zone of 3.2 to 8 km for reduced source terms.