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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.
Gray S. Chang
Nuclear Technology | Volume 122 | Number 1 | April 1998 | Pages 43-51
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT98-A2849
Articles are hosted by Taylor and Francis Online.
The United States and Russia expect to have a surplus of ~150 tonnes of weapons-grade plutonium (WGP) and 1000 tonnes of weapons-grade uranium resulting from drastic reductions in nuclear weapons programs. One of the most favored candidate methods for disposing of the WGP is to blend it with natural or depleted uranium down to 5 to 7 wt% of WGP for light water reactor (LWR) fuel pellet fabrication. However, this approach, with a conversion ratio of 0.6, will produce more plutonium and other actinides in the spent fuel than the nonfertile fuel and the proposed actinide-reduced plutonium fuel (ARPF). This process only transforms the weapons-grade fissile materials to civilian-grade plutonium, which is still a nonproliferation concern, so it does not completely solve the plutonium disposition problem. Disposition of WGP in reactors without fertile material has been proposed by industry and national laboratories. A new ARPF is described that would use WGP mixed with medium-enrichment (20 at.% < 235U < 93 at.%) UO2 and the nonfertile material tungsten to achieve a conversion ratio <0.1. The ARPF can meet the WGP disposal goal while minimizing the plutonium production. Its physics and burnup characteristics are analyzed, and the results are compared with LWR UO2 and mixed-oxide fuel.