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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.
J. B. Yasinsky and A. F. Henry
Nuclear Science and Engineering | Volume 22 | Number 2 | June 1965 | Pages 171-181
Technical Paper | doi.org/10.13182/NSE65-A20236
Articles are hosted by Taylor and Francis Online.
Numerical comparisons have been made between exact and approximate solutions to the two-group space-time diffusion equations. Two slab cores were studied, one 240-cm thick and the other 60-cm thick. Prompt critical bursts and limited ramp insertions of reactivity were simulated by imposing perturbations on the fission cross sections throughout the first quarter of the core. Feedback effects were neglected. Results were obtained using the conventional point kinetics equation, the adiabatic approximation and the space-time synthesis method. For one situation, two nodal methods were also examined. Comparisons with the exact space-time solutions suggest that, when the point kinetics equations are expected on qualitative grounds to be a poor approximation, the actual quantitative errors can be extremely large. Of the other approximations tested the space-time synthesis method gave the most accurate results.
