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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.
John T. Mihalczo
Nuclear Science and Engineering | Volume 20 | Number 1 | September 1964 | Pages 60-65
Technical Paper | doi.org/10.13182/NSE20-60
Articles are hosted by Taylor and Francis Online.
Prompt-neutron lifetimes have been determined for unreflected and unmoderated critical assemblies of enriched-uranium metal (93.15% U235) in cylindrical geometry. Five solid cylinders ranging in diameter from 7 to 15 in. and three cylindrical annuli having outside diameters as large as 15 in. were assembled to delayed critical and their prompt-neutron decay constants measured by the Rossi-α technique. The prompt-neutron lifetimes were determined from the measured decay constants and effective delayed-neutron fractions obtained by Sn multigroup transport-theory calculations, which predicted the multiplication constants of all assemblies to within 1/2%. For the solid cylinders the lifetime value is 6.25 ± 0.04 nsec, which, within the limits of experimental errors, is independent of the dimensions of the cylinders and agrees with the lifetime of 6.2 ± 0.1 nsec obtained from earlier prompt-neutron decay-constant measurements with a uranium sphere (Godiva I). For the cylindrical annuli the lifetime varied from 7.0 to 8.0 nsec. The increase in the lifetime value over that of the solid cylinders is due to the time required for neutrons to cross the center void.
