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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.
Ashok K. Agrawal, Sidney Yip
Nuclear Science and Engineering | Volume 37 | Number 3 | September 1969 | Pages 368-379
Technical Paper | doi.org/10.13182/NSE69-A19113
Articles are hosted by Taylor and Francis Online.
The incoherent neutron scattering cross section of molecular liquids is evaluated using correlation function descriptions of molecular translations and rotations. The calculation is based on the Gaussian approximation for the intermediate scattering function, and the analysis is specifically directed at the energy region of thermal and cold neutrons. Physical models are used to calculate the translational and rotational effects in the mean-square displacement (width) function, or equivalently, the generalized frequency distribution, and it is assumed that translation-rotation couplings can be ignored. The description of center-of-mass motions properly includes the short-time vibrations as well as the long-time diffusion. Different rotational models are discussed, and a simple expression is suggested which relates the rotational correlation function to the Fourier transform of a near infrared vibrational absorption band. Explicit calculations are carried out for liquid methane, and the results are in quite satisfactory agreement with both thermal- and cold-neutron measurements. The results also indicate that inelastic scattering effects are mostly due to rotational motions. Total cross sections are computed and found to agree with experiment (to within 3%) in the range 1-50 × 10−3 eV.
