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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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From operator to entrepreneur: David Garcia applies outage management lessons
David Garcia
If ComEd’s Zion plant in northern Illinois hadn’t closed in 1998, David Garcia might still be there, where he got his start in nuclear power as an operator at age 24.
But in his ninth year working there, Zion closed, and Garcia moved on to a series of new roles—including at Wisconsin’s Point Beach plant, the corporate offices of Minnesota’s Xcel Energy, and on the supplier side at PaR Nuclear—into an on-the-job education that he augmented with degrees in business and divinity that he sought later in life.
Garcia started his own company—Waymaker Resource Group—in 2014. Recently, Waymaker has been supporting Holtec’s restart project at the Palisades plant with staffing and analysis. Palisades sits almost exactly due east of the fully decommissioned Zion site on the other side of Lake Michigan and is poised to operate again after what amounts to an extended outage of more than three years. Holtec also plans to build more reactors at the same site.
For Garcia, the takeaway is clear: “This industry is not going away. Nuclear power and the adjacent industries that support nuclear power—and clean energy, period—are going to be needed for decades upon decades.”
In July, Garcia talked with Nuclear News staff writer Susan Gallier about his career and what he has learned about running successful outages and other projects.
Arthur L. Austin
Nuclear Science and Engineering | Volume 20 | Number 1 | September 1964 | Pages 45-52
Technical Paper | doi.org/10.13182/NSE64-A19273
Articles are hosted by Taylor and Francis Online.
If a thin, unrestrained spherical shell is rapidly heated, large inertial hoop stresses may be developed which result in free oscillation. It has been shown that the dynamic stress amplitude is dependent upon the ratio of heating time to the natural period of oscillation as well as upon the maximum temperature. Since a free shell is rarely encountered in practice, the purpose of this study is to determine the dynamic response of a set of concentric spherical shells when the inner shell only is subjected to rapid, uniform, internal heat generation. The maximum number of shells chosen for analysis is three; however, the method is general and may be applied to systems containing as many concentric shells as desired. The results are presented in parametric form for the stresses in each shell and their dependence upon the material properties. In most reactor-design problems it is desired to maintain the integrity of any system; hence, it is assumed that the inner, heated shell always remains elastic. This represents the extreme stress condition, and may cause yielding of the outer shells. For constraint of the inner shell, the dynamic stresses are obtained for elastic motion and when the outer shell is allowed to flow plastically at constant stress. The special case of instantaneous heating and the effect of composite material properties upon stress amplitudes is considered in detail to provide useful design formulae.
