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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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U.S. nuclear supply chain: Ready for liftoff
Craig Piercycpiercy@ans.org
This month, September 8–11, the American Nuclear Society is teaming up with the Nuclear Energy Institute to host our first-ever Nuclear Energy Conference and Expo—NECX for short—in Atlanta. This new meeting combines ANS’s Utility Working Conference and NEI’s Nuclear Energy Assembly to form what NEI CEO Maria Korsnick and I hope will be the premier nuclear industry gathering in America.
We did this because after more than four decades of relative stagnation, the U.S. nuclear supply chain is finally entering a new era of dynamic growth. This resurgence is being driven by several powerful and increasingly durable forces: the explosive demand for electricity from artificial intelligence and data centers, an unprecedented wave of public and private acceptance of—and investment in—advanced nuclear technologies, and a strong market signal for reliable, on-demand power. Add the recent Trump administration executive orders on nuclear into the mix, and you have all the makings of an accelerant-rich business environment primed for rapid expansion.
Yasushi Nomura, Yoshitaka Naito
Nuclear Technology | Volume 121 | Number 1 | January 1998 | Pages 3-13
Technical Paper | Kiyose Birthday Anniversary | doi.org/10.13182/NT98-A2814
Articles are hosted by Taylor and Francis Online.
Scenario identification, preparation of reliability data, and fault-tree construction were conducted for a criticality in a pulsed column of a typical model of a reprocessing facility to find a weak link in the system. The plant system data, the basic reliability data with the fault-tree analysis code FTL, were supplied from NUKEM GmbH, Germany. In this exercise, a low nitric acid concentration in the scrub flow to the pulsed column is initiated by failures of the reagent preparation system of the primary separation cycle, triggering plutonium accumulation, eventually exceeding the safety limit of the scrub column, and thus a criticality accident occurs. The occurrence frequency was evaluated to be 2.2 × 10-5/yr for this most conservative case of the accident scenario. The main contributor was investigated by the fault-tree branch analysis and identified to be human error relating to the sampling measurement for fresh nitric acid scrub feed. Because 2.2 × 10-5/yr is quite a high value in comparison with the generally accepted 10-6/yr, Monte Carlo uncertainty analysis assuming an error factor of 5 for each of the reliability data was conducted to predict a 90% confidence range of 1.9 × 10-6/yr to 8.25 × 10-5/yr. In addition, there might be unforeseen equipment failures related to the same criticality scenario. The additional analysis and discussion lead to the recommendation to adopt shape and dimension control in the design stage for the whole range of plutonium concentrations from a criticality safety point of view.
