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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.
Robert E. Spears, Efe G. Kurt, Justin L. Coleman
Nuclear Technology | Volume 205 | Number 4 | April 2019 | Pages 624-636
Technical Note | doi.org/10.1080/00295450.2018.1507393
Articles are hosted by Taylor and Francis Online.
Seismic soil-structure interaction (SSI) analysis of nuclear facilities is an important consideration during design and retrofit. SSI tools used in the nuclear industry are currently based on an equivalent linear (EL) approach. Procedures for developing input ground motion for EL approaches are well established. However, the procedures for establishing input ground motion for nonlinear soil-structure interaction (NLSSI) analysis of nuclear facilities are not well established. A collaborative research group at Idaho National Laboratory has recently developed analytical methods and numerical tools for using NLSSI analysis for nuclear facility seismic calculations. NLSSI analysis for a nuclear facility allows for calculation of seismic wave motion through a near-field soil domain using either (a) vertically propagating shear and compressive waves, which is the current industry practice, or (b) a three-dimensional nonvertical wave field. This technical note presents an iterative procedure for establishing outcrop motion at a depth in the soil column for NLSSI analysis that uses vertically propagating shear waves.
The approach presented in this technical note starts with a known ground motion at the surface that is deconvolved to a depth, and then the obtained motion is convolved up to a different desired location of input for the NLSSI model. To demonstrate the validity of the approach, a finite element soil column that is representative of a nuclear facility site in the United States is used to produce compatible outcrop seismic time series for reduced nonlinear soil mesh depths. The developed approach for reducing the nonlinear soil column model depth is a two-step iterative method. The first step is establishing an outcrop time series at the lowest depth considered that produces the top-of-soil response spectrum of an actual recorded ground motion. The second step is providing compatible outcrop time series at a shallower depth based on the information from the first step.
A comparison of the 5% damped response spectrum from the resulting acceleration time series based on the iterated outcrop motions and the original acceleration time series is conducted. The study shows that the proposed iterative approach produced comparable results within 1% range of the original recorded time series results when sufficient iterations were performed.
