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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.
Zhen Wang, Jonny Rutqvist, Yuan Wang, Colin Leung, Andrew Hoch, Ying Dai
Nuclear Technology | Volume 187 | Number 2 | August 2014 | Pages 158-168
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT13-76
Articles are hosted by Taylor and Francis Online.
We present an extended multiple interacting continua (Ex-MINC) model of fractured rock masses that uses Oda's crack tensor theory to upscale the hydraulic and mechanical properties. The Ex-MINC concept includes separate connected continua representing active fractures, inactive fractures, and matrix to represent the fracture-matrix system. The crack tensor theory was used to calculate the stress-dependent permeability tensor and compliance tensor for individual grid blocks. By doing this, we transformed a discrete fracture network model into a grid-based continuum model. The Ex-MINC model was verified against an existing analytical solution, and the entire Ex-MINC/crack tensor model approach was applied to a benchmark test (BMT) related to coupled stress, fluid flow, and transport through a 20-×20-m model domain of heavily fractured media. This BMT was part of the international DECOVALEX project for the development of coupled models and their validation, thus providing us with the opportunity to compare our results with the results of independent models. We conducted the coupled hydraulic and mechanical modeling with TOUGH-FLAC, a simulator based on the TOUGH2 multiphase flow code and the FLAC3D geomechanical code. The results of our simulations were generally consistent with the results of the other independent modeling approaches and showed how inactive fractures impeded solute transport through the fractured system by providing an additional fracture surface area as an avenue for increasing fracture matrix diffusion.