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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.
F. R. Channon, R. L. Seale
Nuclear Science and Engineering | Volume 30 | Number 2 | November 1967 | Pages 242-260
Technical Paper | doi.org/10.13182/NSE67-A17335
Articles are hosted by Taylor and Francis Online.
The behavior of thermal neutrons in a water shield containing ducts was studied experimentally and compared with theoretical models. In addition to measuring the total flux, a source separation technique was used to isolate the various flux components, which are: 1)direct flux, uncollided neutrons which enter the duct mouth 2) scattered flux, collided neutrons which enter the duct mouth 3) penetration flux, collided neutrons which originally enter the shield. Duct diameters from 1 to 4 in. were considered. The shield absorption properties were altered by dissolving various amounts of boric acid in the water. The duct cross-sectional shape was changed by partially flooding the interior of the duct. The experimental results indicated that the direct flux is inversely proportional to distance squared. For sufficiently long ducts, the direct flux is nearly the total flux. For shorter ducts, either the scattered flux or penetration flux may produce the largest contribution to the total flux. Each of these components peak near the duct mouth and then attenuate more rapidly than the direct flux. Successful calculational models were developed for each of the flux components. These permitted determination of the total flux to within a factor of 1.3 at distances greater than two or three duct diameters from the mouth.
