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Nuclear Energy Conference & Expo (NECX)
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.
Bo Eriksson, Claes Johansson, Martin Leimdorfer, M. H. Kalos
Nuclear Science and Engineering | Volume 37 | Number 3 | September 1969 | Pages 410-422
Technical Paper | doi.org/10.13182/NSE69-A19116
Articles are hosted by Taylor and Francis Online.
The integral equation adjoint to the linear transport equation for neutrons is formulated and prescriptions given for its solution by Monte Carlo methods. The process of tracking is the same as for the usual (i.e., forward) Monte Carlo and may be applied to complex geometry. On the other hand, the scattering process is determined by a kernel which is the transpose of the one used in the forward equation. With the help of suitably defined “adjoint cross sections” this transposed kernel may be written as a superposition of density functions for different reaction types in different nuclides. It is then possible to sample nuclide and reaction sequentially as in the familiar Monte Carlo for the forward process. Most emphasis is put upon the solution of the analytical and numerical problems which arise in calculating and sampling the probability distributions which determine these scattering processes. Detailed treatment is given for generating and using the requisite data for elastic scattering, for discrete level and continuum inelastic neutron scattering: and for (n, 2n) reactions.
