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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.
T. J. Williamson, R. W. Albrecht
Nuclear Science and Engineering | Volume 37 | Number 1 | July 1969 | Pages 41-58
Technical Paper | doi.org/10.13182/NSE69-A20897
Articles are hosted by Taylor and Francis Online.
A general model is developed for numerical calculations of neutron slowing down parameters and functions in homogeneous media of any composition. The model is based on a representation of slowing down as a discrete time, discrete state Markov process. It is shown that the weighting function normally used in calculating elements of a multigroup stepping array is not optimal for discrete calculations. An improved weighting function is developed and used to define a model for Markovian transition probabilities. The relation defining Markov n-step transition matrices is utilized to generate stepping matrices that are consistent, accurate, and stable regardless of energy range or time step width. This relation is also used to develop a calculational technique in which a stepping matrix follows the neutron pulse downward in energy, greatly extending the energy range and number of states or groups that may be used in a single calculation. The model is evaluated by comparing the solutions it produces to certain exact solutions of the slowing down equation. It is, in turn, used to evaluate some asymptotic and approximate analytical solutions of the slowing down equation and to explore some problems in slowing down theory.
