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November 9–12, 2025
Washington, DC|Washington Hilton
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October 2025
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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.
S. B. Kim, S. L. Chouhan, P. A. Davis
Fusion Science and Technology | Volume 60 | Number 3 | October 2011 | Pages 960-963
Measurement, Monitoring, and Accountancy | Proceedings of the Ninth International Conference on Tritium Science and Technology | doi.org/10.13182/FST11-A12575
Articles are hosted by Taylor and Francis Online.
The high mobility of tritium as HTO implies that, under steady-state conditions, the T/H ratio (or equivalently the HTO concentration) is the same in all water compartments of the environment. This is the basis of the specific activity (SA) model, which underlies almost all environmental tritium models. SA concepts apply to organically bound tritium (OBT) as well, since the OBT formed by a given plant process at a given time has a T/H ratio that reflects the ratio in the water that enters into that process. There is no empirical evidence that the bioaccumulation of tritium in aquatic and wetland plants will occur. OBT/HTO ratios less than one is consistently found in the laboratory where the HTO concentrations to which the plants are exposed can be held constant. These data suggest a value of 0.7 for the OBT/HTO ratio under equilibrium conditions in the laboratory. Theoretical considerations suggest that the value of the OBT/HTO ratio in plants is significantly different from one and, in most cases, greater than one. This is primarily due to the much longer residence time of OBT in plants as compared to HTO. The observed HTO concentrations are much higher than OBT concentrations, which makes OBT/HTO ratio smaller than unit in contrast with SA based expectations. In addition to this, the IMPACT model overpredicted HTO and OBT concentrations in plants and animals by a factor of 3 or 4, on average. This work is summary of the AECL funded research project (1).
