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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The journey of the U.S. fuel cycle
Craig Piercycpiercy@ans.org
While most big journeys begin with a clear objective, they rarely start with an exact knowledge of the route. When commissioning the Lewis and Clark expedition in 1803, President Thomas Jefferson didn’t provide specific “turn right at the big mountain” directions to the Corps of Discovery. He gave goal-oriented instructions: explore the Missouri River, find its source, search for a transcontinental water route to the Pacific, and build scientific and cultural knowledge along the way.
Jefferson left it up to Lewis and Clark to turn his broad, geopolitically motivated guidance into gritty reality.
Similarly, U.S. nuclear policy has begun a journey toward closing the U.S. nuclear fuel cycle. There is a clear signal of support for recycling from the Trump administration, along with growing bipartisan excitement in Congress. Yet the precise path remains unclear.
P. Kar, G. Danko, J. S. Armijo, M. Misra, D. Bahrami
Nuclear Technology | Volume 155 | Number 1 | July 2006 | Pages 90-104
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT06-A3748
Articles are hosted by Taylor and Francis Online.
Thermal analysis of an alternative boiling water reactor (BWR) waste package design for permanent disposal in the Yucca Mountain Repository is reported in this paper. The new design implements an increase in the holding capacity of the BWR waste packages from 44 to 52 assemblies and a modified arrangement sequence of waste packages in the emplacement drift. The design is favorable from the perspective of a generally drier emplacement drift due to an increase in heat load in the waste packages and the resulting higher temperatures. The analysis addresses heat transfer issues inside the waste package and those pertinent to satisfying the safe thermal limits for the waste package components. Key parameters in the analysis are the spent nuclear fuel assembly effective conductivities, the number of aluminum shunts, and the gap backfill with pressurized helium inside the waste packages. The feasibility of the proposed design is demonstrated by the internal waste package thermal model and the thermal-hydrologic environment in the emplacement drift. The conformity of the alternative thermal design to safe temperatures, in spite of the additional heat load, led to another innovative design with radial arrangement of assemblies in the waste packages that would further support the sustenance of drier emplacement drifts. These radial configurations are also discussed in this paper.
