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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. M. Chapman, C. M. Huddleston
Nuclear Science and Engineering | Volume 25 | Number 1 | May 1966 | Pages 66-74
Technical Paper | doi.org/10.13182/NSE66-A17502
Articles are hosted by Taylor and Francis Online.
Methods are outlined for computer calculation of first- and second-order contributions to gamma-ray dose rates in two-legged rectangular concrete ducts of personnel shelters. Four computer programs, based on values of differential dose albedo derived from Monte Carlo calculations, are used to calculate corner-lip inscattering, backscattering from surfaces visible to both source and detector, and combinations of these two scattering events. The first program computes the dose contribution from corner-lip inscatter and from combinations of corner-lip penetration and wall backscatter. The second calculates first-order backscatter from the basic scattering areas in the corner of the duct. The third computes the second-order backscatter contribution from two successive backscatters from the duct walls. The final program calculates the contribution due to combinations of one wall backscatter and one corner-lip inscatter. The results of the calculations are compared with experimental results obtained by several investigators. The experimental studies used 11 × 11-in., 3 × 3-ft, and 6 × 6-ft ducts; the gamma-ray sources were, variously, 198Au, 137Cs, 60Co, and 24Na. Since the difference between calculated and measured values of gamma-ray dose in the second leg is generally less than 30%, results obtained by calculation can be used to predict the attenuation factors of two-legged concrete ducts and entranceways leading into personnel shelters with an expected error of less than 30%.
