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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.
Adnan A. Aswad, G. R. Dalton
Nuclear Science and Engineering | Volume 24 | Number 1 | January 1966 | Pages 49-59
Technical Paper | doi.org/10.13182/NSE66-A18123
Articles are hosted by Taylor and Francis Online.
The one-velocity time-independent neutron integro-differential transport equation is converted into an integral equation by the use of a homogeneous Green's function. The neutron flux, Green's function, and source are expanded in spherical harmonics. The integrations over the angles are carried out by the use of the spherical harmonic orthogonality relation. The net result is a set of coupled integral equations in the flux angular moments. Relations that give the Green's function angular moments are derived for any nonreentrant geometry and all boundary conditions applicable to the neutron transport equation. The conditions for which the scalar flux and some of the flux higher moments can be calculated exactly are discussed. Sample problems of unit slab cells that meet these conditions, are solved. The results are found to be in excellent agreement with those of the DS16 and the TRANVAR codes. A method to estimate the effect of the flux non-zeroth angular moments and the spatial truncation errors on the scalar flux is introduced. A sample problem of a heterogeneous unit slab cell is presented. It is found that the errors in the scalar flux due to neglecting the flux non-zeroth angular moments and the spatial truncation error are each of the order of 0.03% for this problem.
