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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Joonhong Ahn
Nuclear Technology | Volume 126 | Number 3 | June 1999 | Pages 303-318
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT99-A2976
Articles are hosted by Taylor and Francis Online.
An assessment for the criticality safety of a conceptual repository for vitrified high-level radioactive waste from reprocessed fuel of commercial light water reactors in a water-saturated granitic rock has been performed by quantitatively estimating the mass of fissile 235U existing in the entire far field as the performance measure. The uncertainties associated with the performance measure have been obtained by a statistical analysis with the Latin hypercube sampling method.With the assumed probability distribution functions for the model parameters, the mass of 235U released from the repository and existing in the far field at 100 million years is estimated to be <40 kg with a 90% confidence level. This implies that all 235U existing in the entire far field at that time must accumulate in a single location for an overmoderated criticality event to occur in granitic rock.
