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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.
Hangbok Choi, Myunghee Choi, Ryan Hon
Nuclear Technology | Volume 205 | Number 3 | March 2019 | Pages 486-505
Technical Paper | doi.org/10.1080/00295450.2018.1495001
Articles are hosted by Taylor and Francis Online.
Calculations have been conducted for the KRITZ-2 (KRITZ-LWR-RESR-001/002/003) and the Fast Flux Test Facility (FFTF) (FFTF-LMFR-RESR-001) Nuclear Energy Agency benchmark problems using the PARCS reactor simulation code with lattice parameters generated by the DRAGON reactor physics code and with the MCNP6 Monte Carlo code. The benchmark analyses examined the DRAGON cross-section library, PARCS energy group structure, DRAGON fuel assembly modeling, and nuclide self-shielding effect. For KRITZ-2, the PARCS 2-group core calculations with a DRAGON 361-group library based on ENDF/B-VII.1 reproduced the benchmark keff with a root-mean-square (rms) error of 0.19% δk. DRAGON/PARCS also predicted the fission rates within 5%. The MCNP results are consistent with the DRAGON/PARCS results but with a small underestimation when compared to the benchmark value. For FFTF, the PARCS 33-group core calculations underpredicted the benchmark keff by 0.19% δk while the MCNP calculation overpredicted the benchmark keff by 0.23% δk. The neutron spectrum distributions calculated by PARCS and MCNP are consistent with measured data. Since the energy boundary values of the measured neutron spectrum are not available, the calculated spectra could not be directly compared to the measured value. The DRAGON/PARCS solution to a numerical benchmark of a gas-cooled fast reactor (GFR), i.e., the Energy Multiplier Module, predicted the keff and assembly power with 0.46% δk and 3.7% rms error, respectively, when compared to the MCNP simulation. The benchmark calculations of the selected thermal and fast reactors have shown that DRAGON/PARCS simulates small reactor cores with good accuracy.
