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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.
Harry McNeill, Martin Becker
Nuclear Science and Engineering | Volume 42 | Number 2 | November 1970 | Pages 220-229
Technical Paper | doi.org/10.13182/NSE70-A19502
Articles are hosted by Taylor and Francis Online.
Acoustic wave propagation in a gaseous core nuclear rocket is investigated by a theoretical model. Slab geometry in a long initially uniform cavity is assumed for simplicity and the reflector-heat sink is taken to be of infinite thickness. Blackness theory is used to determine the transmission of thermal neutrons (and thereby the generation of heat) in the fissionable gas of the cavity. Mutual feedback between neutron dynamics and gas dynamics occurs by means of the density-dependence of the blackness coefficients. Numerical results indicate that neutronic feedback can be a significant influence toward stabilization of acoustic oscillations. The critical wave length (which is twice the critical core length) without neutronic feedback is calculated to be 100 cm while critical wave lengths of 150 and 232 cm were obtained for carbon and beryllium reflectors, respectively. These results show that the critical core lengths are still comparable to or shorter than typical reference core lengths (300 cm). Thus, while neutronic feedback has an effect on acoustic instability, the effect is not strong enough to alter the general conclusion that acoustic instability is a potential problem area for gaseous reactor development.
