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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.
J. C. Kang, J. S. Jeong, D. H. Lee, T. L. George, J. W. Lane, S. G. Thomasson
Nuclear Technology | Volume 207 | Number 12 | December 2021 | Pages 1851-1864
Technical Paper | doi.org/10.1080/00295450.2020.1858628
Articles are hosted by Taylor and Francis Online.
GOTHIC and RELAP5 have been coupled to model the containment and passive containment cooling system (PCCS) for the Korean advanced containment designs. In the coupled system, GOTHIC models the containment and the outer shell (mid tube wall to outside surface) of the PCCS heat exchanger tubes and RELAP5 models the inner shell (inside surface to mid tube wall) and the coolant loop to the external heat sink. The coupling approach leverages the modeling capabilities of RELAP5 for piping load analysis and the capabilities of GOTHIC for containment and heat/mass transfer with noncondensing gases. With the coupled model, it is possible to apply the thermal-hydraulic load analysis on the PCCS supply and return piping considering the containment conditions predicted by GOTHIC during a loss-of-coolant accident (LOCA). This paper describes the coupling approach, a coupling dynamic linked library for GOTHIC, modifications to RELAP5, and verification of the coupling. Last, demonstration results from a LOCA simulation with four PCCS trains is provided and the results of the GOTHIC/RELAP5–coupled model are compared to a GOTHIC-only result, where GOTHIC was used to model both the containment and the PCCS.