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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.
Yecheng Yu, Ping Tan, Yinjie Lin, Yuying Hu, Huidong Guo, Hao Lei, Zhongqi Zhang, Jiadong Li, Delin Hu
Nuclear Technology | Volume 207 | Number 2 | February 2021 | Pages 299-315
Technical Paper | doi.org/10.1080/00295450.2020.1747839
Articles are hosted by Taylor and Francis Online.
A proton therapy facility based on an isochronous superconducting cyclotron is under constructed at the Proton Therapy Facility of the Huazhong University of Science and Technology. Due to the limitation of minimum energy extracted by the energy selection system in the upstream beamline, a range shifter is installed at the end of the nozzle to further decrease the proton beam energy so that the shallow-seated tumors can be treated. In this paper, the physical structure, energy degradation scheme, and material optimization selection of the range shifter are discussed and analyzed by Monte Carlo simulation software Geant4 and FLUKA. At the same time, the treatment outcome on the energy degradation process and its influence on the synthesis of spread-out Bragg peak (SOBP) in the treatment plan system after the application of the range shifter are analyzed. The results show that by using a high-density polyethylene energy-degrading plate with a thickness of 42.35 mm, combined with two 30-mm copper collimators, the range shifter can achieve a good energy-degradation effect while significantly reducing the beam horizontal penumbra at the edge of the radiation field. At the same time, the addition of the range shifter can reduce the number of the energy level required to form the SOBP and shorten the treatment time, but it will inevitably lead to a slight increase in the longitudinal penumbra.