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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. Appel and B. Roos
Nuclear Science and Engineering | Volume 34 | Number 3 | December 1968 | Pages 201-213
Technical Paper | doi.org/10.13182/NSE68-A21086
Articles are hosted by Taylor and Francis Online.
An exact formulation is presented for the release of metallic fission products. Such radioactive atoms are created through fission processes inside the kernel of fuel particles. They can diffuse through the coating of a fuel particle and the surrounding charcoal matrix into the structural graphite of the reactor core. Some atoms traverse this graphite along internal surfaces and finally enter the coolant gas. To find the number of radioactive atoms released into the coolant gas, the diffusion equation in one space dimension is solved numerically taking into account as driving forces both the gradient of the chemical potential and that of the temperature field. The chemical potential is determined respectively by the Langmuir and Freundlich adsorption isotherms for small and large concentrations of metal atoms adsorbed at the highly active internal surfaces of charcoal and graphite. As an example, a parameter study of the release is presented for the most danagerous radioactive metallic isotope, 90Sr. The calculation of the release rate from a single fuel particle shows that the coating does not act as an effective diffusion barrier in this case. It is found that the structural graphite governs the release by virtue of its good adsorptive properties and its low diffusion constant. The results for the concentration profile, the mass current (or flux), and the release of 90Sr are highly sensitive to experimental information on diffusion and adsorption coefficients, in part because of the temperature-activated nature of adsorption and diffusion processes. Since the experimental variables are known with limited accuracy only, a parameter study of the 90Sr release is carried out, that is centered around the best available empirical values for diffusion and adsorption coefficients.
