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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. Dorning
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 65-80
Technical Paper | doi.org/10.13182/NSE68-A20919
Articles are hosted by Taylor and Francis Online.
The pulsed-neutron experiment discrete time-decay constants are examined in slab and spherical geometries using a one-term degenerate isotropic scattering kernel. The integral form of the space-, energy-, and time-dependent neutron-transport equation is considered in the proof of four theorems that determine the nature of the decay constants as a function of system size. The theorems are verified by actual calculation of the decay constants for the simpler of the two degenerate-kernel models considered. The spatial eigenfunctions that become flatter as system size is decreased are also computed. The one-velocity problem is solved as a special case. Pulsed-neutron experiment size-dependent extrapolation distances are defined and calculated in such a way as to bring exp (iB · r) theory decay constant results into agreement with those obtained by a more rigorous treatment of the spatial dependence, even for vanishingly small systems. Again, the monoenergetic problem is included as a special case. The variable extrapolation distances approach the Milne problem value as system size is increased. The variation of the extrapolation distance with system dimension is discussed in terms of opposing effects of the thermalization and transport phenomena. Estimates of leakage angular distributions and energy spectra in slabs are calculated from single iterations (performed analytically) on spatial functions synthesized from asymptotic solutions using the size-dependent extrapolation distances. The nature of the singularity in the angular distributions within extremely small systems is investigated. Finally, physical explanations for the changes in the leakage angular distributions and energy spectra (which are diffusion cooled) with slab dimensions are proffered.