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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.
H. Guo, P. Sciora, T. Kooyman, L. Buiron, G. Rimpault
Nuclear Technology | Volume 205 | Number 11 | November 2019 | Pages 1433-1446
Technical Paper | doi.org/10.1080/00295450.2019.1620054
Articles are hosted by Taylor and Francis Online.
Generation IV reactors are expected to exhibit significant safety improvements compared to current ones. In sodium-cooled fast reactors (SFRs), fuel melting during transient over power (TOP) should be avoided as this is identified as a relatively frequent accident. Among these TOP accidents, a control rod withdrawal (CRW) accident is the most likely to happen and its impact depends on the magnitude of the inserted reactivity. This paper presents the required excess reactivity for different core designs and the way to reduce the reactivity inserted during a CRW transient through the use of burnable poisons (BPs).
After evaluating various candidate materials, it appears that a low-enrichment boron carbide combined with a zirconium hydride moderator is the most promising BP for use in sodium fast spectrum reactors. Burnable poisons are located in pins of particular assemblies, which are in fixed positions in the core over the entire fuel cycle.
Four core designs with different loading schemes and BPs are investigated. Core designs with BPs display low reactivity loss over the fuel cycle and thus limit the required initial excess reactivity of the core to compensate with control rods.
Another constraint comes from the core power distribution, which should remain almost stable through the fuel cycle. This core power distribution can be modified by a suitable loading of BP assemblies. However, as their positions are fixed over the fuel cycle, they can compensate only part of the local flux tilt. These BP core designs slightly improve the reactivity feedback coefficients as they contain light materials slowing down neutrons. It is finally shown that a CRW transient with BPs reduces significantly the maximal fuel centerline temperature compared to a design without BPs and that a fuel melting during a CRW transient is avoided in the large SFR core.