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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. J. Volpe, J. Hardy, Jr., D. Klein
Nuclear Science and Engineering | Volume 40 | Number 1 | April 1970 | Pages 116-127
Technical Paper | doi.org/10.13182/NSE70-A18883
Articles are hosted by Taylor and Francis Online.
Thermal disadvantage factors and spectral indexes have been measured in a variety of light-water-moderated lattices. One series contained slightly enriched uranium rods in hexagonal geometry and another series used natural-uranium fuel in slab geometry. The detectors used were 164Dy, 176Lu, and 239Pu. Full energy range (0 to 10 MeV) Monte Carlo calculations with explicit cell-geometry representations were performed using the RECAP program. In addition, thermal energy range (0 to 0.625 eV) calculations were obtained with the Monte Carlo program MARC as well as with the integral transport-theory-code THERMOS. The purpose of these investigations was to test the adequacy of the various water scattering kernels—Nelkin, Koppel, and Haywood—for a broad range of thermal-flux characteristics: from a soft moderator spectrum with a steep spatial gradient to a very hard spectrum which was relatively flat as a function of position. The conclusions obtained were as follows. Calculated spectral indexes using the Haywood kernel were 2 to 3% higher than experiment, on the average, in the fuel region of these cells. Use of the Koppel kernel removed most of this disagreement in the case of 176Lu but the comparison for 239Pu remained unchanged. On the basis of these results, the thermal-flux spectrum obtained with the Haywood model appears to be slightly too hard. With regard to the disadvantage factors, good agreement was generally obtained between theory and measurement except for the tightest lattices. The calculated disadvantage factors were found to be insensitive to the kernel model selected. The effects from including thermal-scattering-pattern treatments above P1 as well as a spatially dependent and anisotropic source-to-thermal description were found to be small in these cells, < 2%.
