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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.
E. E. Lewis, F. T. Adler
Nuclear Science and Engineering | Volume 31 | Number 1 | January 1968 | Pages 117-126
Technical Paper | doi.org/10.13182/NSE68-A18014
Articles are hosted by Taylor and Francis Online.
A method has been developed for calculating resonance effects in nuclear reactor lattices without the two widely used assumptions: 1) that the neutron flux is spatially independent within each region of the lattice cell; 2) that the flux recovers an asymptotic l/E form between resonances. The neutron slowing down problem is formulated in terms of a Boltzmann integral equation, and the correct transport kernel is derived for a Wigner-Seitz equivalent cell with isotropic scattering in the laboratory system. A new method of polynomial approximations is then used to reduce the transport problem to matrix form. The result is a set of integral equations in lethargy for the neutron flux at a number of discrete ordinates. These equations are numerically integrated to obtain the neutron flux as a function of position and energy. Resolved resonance integrals are calculated for a number of 238U-graphite lattices with both metal and oxide rods. Where comparisons are made, the results are in excellent agreement with accurate Monte Carlo calculations. Both the flat flux and flux recovery assumptions are found to cause significant overestimates of the resonance integrals, the errors increasing with the rod radii. The temperature coefficients, however, are less sensitive to these assumptions.
