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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.
Sungwhan Cho, Jin Jiang
Nuclear Technology | Volume 161 | Number 2 | February 2008 | Pages 98-107
Technical Paper | Reactor Safety | doi.org/10.13182/NT08-A3916
Articles are hosted by Taylor and Francis Online.
A new technique for analyzing the effect of testing on shutdown system (SDS) number 1 (SDS1) in Canadian deuterium uranium (CANDU) nuclear power plants is proposed. The effect of the test on the core damage probability is quantified using a Markov process model. The model is used to derive the effect of the test frequency on the unavailability and the spurious reactor trip probability. Two core damage scenarios are considered: one from a process failure with the unavailable SDS and the other from a spurious reactor trip. The Markov process model is then used with the core damage scenarios to analyze the effect of the test frequency on the core damage probability. The quantified core damage probabilities indicate that performing more frequent surveillance tests does not necessarily decrease the risk. In fact, there exists an optimal test frequency beyond which the probability of core damage starts to increase. This optimal test frequency is of significance in practice.