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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
Jeffrey A. Moore
Nuclear Technology | Volume 67 | Number 1 | October 1984 | Pages 66-72
Technical Paper | Nuclear Safety | doi.org/10.13182/NT84-A33530
Articles are hosted by Taylor and Francis Online.
The nonrandom packing of fuel rod debris around and above the surviving fuel rod segments in a degraded core was analyzed with the spacer grids modeled as a porous floor. The irregular shape of the debris was simulated by assuming that all of the spherical particles terminate their migration within the debris bed at their first two-point contact. The analytical approach was verified by comparing the computational results with experimental data for nonrandom packing. Specific calculations for the Three-Mile Island Unit 2 geometry reveal an average (horizontally integrated) nonrandom packing density between the fuel rods of ∼0.30. If simulated vibrations are imposed, this value increases to 0.50. If the debris bed builds up above the fuel rod stubs, the average (horizontally integrated) packing density above these rods reaches a value of ∼0.38 without vibrations; loosely packed gravel has an average random packing density of 0.45.
