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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.
Diego Mandelli, Andrea Alfonsi, Congjian Wang, Zhegang Ma, Carlo Parisi, Tunc Aldemir, Curtis Smith, Robert Youngblood
Nuclear Technology | Volume 207 | Number 3 | March 2021 | Pages 363-375
Technical Paper | doi.org/10.1080/00295450.2020.1776030
Articles are hosted by Taylor and Francis Online.
A new generation of dynamic methods has started receiving attention for nuclear reactor probabilistic risk assessment (PRA). These methods, which are commonly referred to as dynamic PRA (DPRA) methodologies, directly employ system simulators to evaluate the impact of timing and sequencing of events (e.g., failure of components) on accident progression. Compared to classical PRA (CPRA) methods, which are based on static Boolean logic structures such as fault trees and event trees (ETs), DPRA methods can provide valuable insights from an accident management perspective. However, as of today this class of methods has received limited attention in practical applications. One factor is DPRA research and development has progressed mostly as an alternative to state-of-practice CPRA methods (i.e., disconnected from currently employed PRA methods). This disconnect is addressed in this paper by presenting several algorithms that can be employed to bridge the gap between CPRA and DPRA. First, algorithms designed to identify differences between CPRA and DPRA results are presented. The identification process compares the CPRA ET sequence or the minimal cut sets (MCSs) obtained by CPRA with the set of transients simulated by the DPRA. If inconsistencies are observed, solutions are provided to incorporate these differences back into the CPRA by employing DPRA to inform existing CPRA. We performed this incorporation either probabilistically (e.g., by updating MCS probability) or topologically (by adding new branching conditions or sequences in the ET).