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Nuclear Energy Conference & Expo (NECX)
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.
Reimar Froehlich
Nuclear Science and Engineering | Volume 34 | Number 1 | October 1968 | Pages 57-66
Technical Paper | doi.org/10.13182/NSE68-A19366
Articles are hosted by Taylor and Francis Online.
The existence of a unique positive critical flux distribution and of a corresponding single positive eigenvalue (k-effective), which is greater than the absolute value of any other eigenvalue, is established for the discrete form of the steady-state multigroup diffusion equations. The assumptions here are considerably less restrictive than in formerly published papers. For example, arbitrary scattering matrices, general fission transfer matrices (not necessarily in multiplicative form), and internal nondiffusion regions are allowed. Furthermore, the transitivity assumption of the problem is replaced by weak conditions of connectedness, which are not only sufficient but also necessary for the existence statements. The theoretical and computational significance of the existence and positivity theorems are discussed. Several examples illustrate the generality of the results and the importance of the conditions of connectedness.
