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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.
Weston M. Stacey, Jr.
Nuclear Science and Engineering | Volume 29 | Number 2 | August 1967 | Pages 254-263
Technical Paper | doi.org/10.13182/NSE67-A18535
Articles are hosted by Taylor and Francis Online.
Analytical expressions for the spatially independent spectrum and importance (adjoint) function in fast-reactor assemblies have been developed. These expressions were obtained by solving the neutron balance equation, and the equation adjoint thereto, by the method of successive approximation. Solutions obtained in this manner suggest an interpretation of the collision density in terms of the probability that a fission neutron suffers a given sequence of scattering collisions, summed over all such sequences. Similarly, the importance function is interpreted in terms of the fission-neutron production probability following a given sequence of scattering collisions, summed over all such sequences. The analytical expressions are readily evaluated using either differential or group-averaged cross-section values. Integral properties of highly enriched and dilute fast-reactor assemblies were evaluated and compared with experiment; the agreement was comparable with that obtained with multigroup calculations normally employed to evaluate such assemblies.