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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.
Thierry Cadiou, Jacky Louvet
Nuclear Technology | Volume 153 | Number 3 | March 2006 | Pages 256-263
Technical Paper | Sodium Technology - Reactor Safety | doi.org/10.13182/NT06-A3705
Articles are hosted by Taylor and Francis Online.
Upon request of the French Safety Authorities, the transient phase, initiated by a total instantaneous blockage (TIB) in a Phénix reactor fuel assembly, has been investigated. Based on an experimental program performed with the SCARABEE reactor, the phenomenology of the accident is first presented. The SIMMER code, which models fast reactor core disruptive accidents, is then used to analyze the transient phase in order to establish the chronology of the events occurring in the faulty assembly after its blockage. This study concludes that the time between the TIB and the onset of structure melting in the neighboring assemblies is sufficient to scram the reactor by control rod insertion before propagation of the accident to the rest of the core.