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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.
Hiroshi Takahashi
Nuclear Science and Engineering | Volume 41 | Number 2 | August 1970 | Pages 259-270
Technical Paper | doi.org/10.13182/NSE70-A20712
Articles are hosted by Taylor and Francis Online.
The Monte Carlo method is applied to calculate the reactivity change due to a moving reflector block in the pulsed fast reactor system. This reactivity change is an important quantity in the determination of the power pulse width. In the important region of small displacements about the maximum reactivity point, the reactivity change is so small that the ordinary Monte Carlo methods, using the importance sampling, Russian roulette, or splitting techniques, require prohibitively long calculation times. To avoid this difficulty, a new Monte Carlo method, which directly calculates the geometry coefficient of reactivity due to a geometry perturbation, is developed by adopting the method used in the calculation for the Doppler coefficient by Olhoeft. The formulation of the new method is discussed. The GEMCM code for this geometry perturbation, which is made by modifying the 05R code, is described. Finally, an analysis of the critical experiment for the pulsed fast reactor is carried out using this method and the applicability of the method is discussed.
