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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.
S. Wang, T. Beuthe, X. Huang, A. Nava Dominguez, A. V. Colton, B. P. Bromley
Nuclear Technology | Volume 207 | Number 4 | April 2021 | Pages 469-493
Technical Paper | doi.org/10.1080/00295450.2020.1788302
Articles are hosted by Taylor and Francis Online.
The use of advanced uranium-based and thorium-based fuel bundles in pressure tube heavy water reactors (PT-HWRs) has the potential to improve the utilization of uranium resources while also providing improvements in performance and safety characteristics of PT-HWRs. Previous lattice physics and core physics studies have demonstrated the feasibility of using such advanced fuels; however, thermal-hydraulic (T-H) studies are required to confirm that these advanced fuels will have adequate T-H safety margins. Preliminary system T-H transient simulations have been performed for a 700-MW(electric)–class PT-HWR in a postulated loss-of-coolant accident (LOCA) using the CATHENA code. One purpose of this work was to demonstrate that such simulations of a PT-HWR with advanced fuels could be set up and executed successfully in a CATHENA transient simulation model. The other purpose was to evaluate the peak fuel sheath and fuel centerline temperatures in two designated fuel channels containing advanced uranium-based or thorium-based fuel during a LOCA transient event. In the CATHENA simulation models, a PT-HWR core is fueled with conventional 37-element natural uranium fuel bundles in 378 out of 380 fuel channels while two designated fuel channels, the channel with the highest total power and the channel containing the bundle with the highest power level, are filled with various types of advanced fuels. Results indicate that setting up these models is feasible and that the predicted peak fuel centerline temperatures and peak sheath temperatures for the advanced fuel channels are well below the fuel melting points and the rapid oxidation temperature for the Zircaloy-4 sheath/clad (~1200°C), respectively. These preliminary results provide confidence that the advanced fuels will likely have adequate T-H safety margins in a transient LOCA event in a PT-HWR. These results set the stage for more detailed and comprehensive system T-H models of PT-HWRs fueled entirely with advanced uranium-based or thorium-based fuels.
