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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.
L. A. Hageman, J. B. Yasinsky
Nuclear Science and Engineering | Volume 38 | Number 1 | October 1969 | Pages 8-32
Technical Paper | doi.org/10.13182/NSE38-8
Articles are hosted by Taylor and Francis Online.
Alternating-direction implicit (ADI) time-differencing approximations are developed for the two-dimensional neutron group-diffusion equations. These methods are analyzed for accuracy and stability relative to the implicit-difference approach used in the TWIGL program. It is shown that for model problems (bare homogenous reactors with constant material properties) the ADI method is as accurate as the TWIGL method and much faster computationally. However, several numerical comparisons show that the ADI approach is asymptotically unstable for non-model problems unless extremely small time-steps are used. Such comparisons show the ADI methods (considered in this paper) to be inferior to the TWIGL method for realistic reactor-dynamic problems. A variant on the ADI scheme (ADI-B2) is developed and for a class of delayed supercritical problems shown to be potentially superior to all methods considered.
