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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. T. Wajima, H. Yamamoto, H. Kikuchi, T. Ohnishi, S. Kobayashi
Nuclear Science and Engineering | Volume 31 | Number 1 | January 1968 | Pages 19-31
Technical Paper | doi.org/10.13182/NSE68-A18004
Articles are hosted by Taylor and Francis Online.
The microparameters including the thermal-neutron disadvantage factor, DF, the epi- to sub-Cd neutron capture ratio in 238U, ρ28, the epi- to sub-Cd fission ratio in 235U, δ25, and the ratio of the epi-Cd 238U fission to the sub-Cd 235U fission, δ28, were measured in the Ozenji Critical Facility for a seven-rod clustered nuclear superheat fuel element. The factors f, p, and ϵ were derived therefrom and the effect of 235U epithermal fissions on the neutron multiplication factor was observed to be 1.5% Δk/k. Flooding changed the individual factors f, p, and ϵ by amounts corresponding to −6.8% Δk/k, +4.7% Δk/k, and −2.9% Δk/k, respectively, yielding an overall change of −5.1% Δk/k. The maximum discrepancies between measurement and calculation are 1 to 3% for DF, ρ28 , δ25, and δ28; 0.3% Δk/k for f, p, and ϵ; and 0.4% Δk/k for the infinite multiplication factor. The calculation of the effects of flooding on f, p, ϵ, and the infinite multiplication factor agrees with the experiment to within 0.3 to 0.4% Δk/k. When performing the cell calculations, care was taken to determine how to cylinderize the unit cell to perform the one-dimensional calculations with the THERMOS code, how to select the value of the L factor to be used in the JUPITER code (modified MUFT) and how to incorporate the heterogeneous effect of fast fissions.
