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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.
R. M. Carroll, J. G. Morgan, R. B. Perez, O. Sisman
Nuclear Science and Engineering | Volume 38 | Number 2 | November 1969 | Pages 143-155
Technical Paper | doi.org/10.13182/NSE69-A19519
Articles are hosted by Taylor and Francis Online.
Two cylindrical specimens of UO2 were irradiated in the Oak Ridge Research Reactor at temperatures up to 1700°C. Both specimens were of natural enrichment uranium (0.7% 235U) but one specimen was a single crystal and the other had a fine-grain microstructure. The fission-gas release from these specimens were affected by the fission density, temperature, burnup, grain growth, and the cracking of the specimens. Concentrations of fission gas produced high local stresses which contributed to the cracking of the specimens. Spherical specimens of enriched (48.7% 235U), fused, polycrystalline UO2 were irradiated to study the effect of burnup and high fission density. The spherical specimens began breaking at 1.9% uranium burnup and continued to break into smaller fragments as the burnup continued to 4.6% uranium burnup. The primary cause of breaking was fission-gas pressure within the spheres rather than thermal stresses. Equiaxed grain growth in UO2 occurs at ∼1650°C and fission gas, normally trapped in a grain boundary, can then migrate along the mobile grain boundary. The fission-gas release rate is thus greatly increased during the time of grain growth but the increase in grain size has little influence on the subsequent gas release at lower temperatures. By the defect-trap model, the effect of an increase in fission density is to create more traps within the fuel and at the same time to generate more fission gas. Thus, although the concentration of fission gas within the specimen is proportional to the fission density (at equilibrium conditions) the escape rate of the fission gas is not proportional to the concentration, unless the fission density is very low. When the fission density is very high, however, the fission tracks will intersect and the fission gas may escape as if through interconnected diffusion pipes. The fission-gas release was found to increase exponentially with fission density above 1014 fissions/(cm3 sec).
