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NRC issues draft EA/FONSI for Duane Arnold restart
Efforts by NextEra Energy to restart the Duane Arnold nuclear power plant as early as 2029 continue to move forward with the Nuclear Regulatory Commission's preliminary environmental assessment and determination that the restart would have no significant environmental impacts.
On Thursday, the NRC posted a draft environmental assessment and a finding of no significant impact for the Palo, Iowa, facility; the Federal Register notice was published on Monday. The Department of Energy’s Office of Energy Dominance Financing is a cooperating agency on the draft EA, as the DOE is considering providing financial assistance to the restart project.
Peter H. Titus, H. Zhang, A. Lumsdaine, W. D. McGinnis, J. Lore, H. Neilson, T. Brown, J. Boscary, A. Peacock, Joris Fellinger
Fusion Science and Technology | Volume 68 | Number 2 | September 2015 | Pages 272-276
Technical Paper | Proceedings of TOFE-2014 | doi.org/10.13182/FST15-105
Articles are hosted by Taylor and Francis Online.
Early implementation of divertor components for the Wendelstein 7-X stellarator will include an inertially cooled system of divertor elements called the Test Divertor Unit (TDU). One part of this system is a scraper element that is intended to explore methods of mitigating heat flux on the ends of the TDU elements. This system will be in place in 2017, after a run period that will involve no divertor, and will precede steady state operation with actively cooled divertors scheduled for 2019. The TDU scraper element is an experimental device with uncertain requirements and with loading conditions which will developed as a part of the experiment. The pattern of heat flux may vary from currently predicted distributions and intensities. The design of the scraper element must accommodate this uncertainty. Originally the mechanical design was to be based on extensive studies for the monoblock-based design of an actively cooled system. An obvious simplification is the elimination of the manifolding needed for the water cooling. The wall panels on which the panels are mounted are to be maintained at 200C or less. Thermal ratcheting of the tiles, supporting structures, and backing structures is managed with adequate cooldown times, thermal anchors, where allowed, and radiative shields. Water cooling of the shields was proposed and rejected. Better radiation modeling is showing less need for multiple shields, but during initial run periods, the scraper element will have to be restricted to an acceptable operating envelope. Thermal instrumentation is recommended.