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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.
Erhard A. Fischer, Werner Maschek
Nuclear Technology | Volume 71 | Number 1 | October 1985 | Pages 173-186
Technical Paper | Nuclear Safety | doi.org/10.13182/NT85-A33718
Articles are hosted by Taylor and Francis Online.
The role of vapor bubble dynamics during an energetic superprompt critical power excursion in a liquid-metal-cooled fast breeder reactor (LMFBR) unprotected loss-of-flow accident is examined by extending a known bubble dynamics model to the case of a rapid temperature rise. Generally, bubble dynamics is expected to influence such an excursion in at least two ways: 1. The fuel vapor pressure buildup—an important shutdown mechanism for the nuclear excursion—could be delayed by limiting the fuel evaporation rate; this would mean large superheat of the liquid fuel. 2. Shrinkage of initially present bubbles during the excursion could cause a strong reduction of neutron streaming, and therefore increase the reactivity of the system (potential of an autocatalytic effect). Both problems have been studied in this paper, and the following results have been obtained: For the rather high heating rate of 400 K/ms, fuel vapor bubbles grow for typically 1.5 ms, and then shrink again due to the rapidly rising pressure. Growth rates are found to be fast enough so that the expected delay in vapor pressure buildup is small and can be neglected in core disassembly analysis. The case that the initial configuration is a boiling fuel/steel pool was further examined. The pool has a high void fraction due to the presence of steel vapor bubbles. Collapse of these bubbles during a temperature transient was studied with the bubble dynamics model. The associated reduction in the neutron streaming effect leads to an increase in reactivity. Its influence on the nuclear excursion was examined with the core disassembly code KADIS, using a modified Behrens formula for the streaming reactivity. The data of a homogeneous 300-MW(electric) class LMFBR were used, with a 33 dollar/s reactivity ramp resulting from a recriticality driven by fuel compaction. Although the total streaming reactivity is as large as 2.32 dollars, it was found that its influence on the course of the power transient is only weak, because the bulk of it is released, at a high rate, only after the power peak, when nuclear shutdown by gross material motion is already in progress.
