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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.
D. C. Leslie, A. Jonsson
Nuclear Science and Engineering | Volume 23 | Number 1 | September 1965 | Pages 82-89
Technical Paper | doi.org/10.13182/NSE65-A19261
Articles are hosted by Taylor and Francis Online.
In a previous paper Leslie, Hill and Jonsson put forward a method for the rapid evaluation of the Dancoff factor in regular arrays of fuel rods. They also showed how extended rational approximations to the fuel nonescape probability could be used to improve the form of the equivalence theorem based on Wigner's rational approximation. This form of equivalence asserts that the resonance integral is a function of the geometry through the excess potential scattering 1/N only, where N is the number density of the absorber and is the mean chord. In the modification proposed by Leslie, Hill and Jonsson, this function is generalized to a/N; the Bell factor a is found to vary with coolant density. By making use of an approximate analytic method for the calculation of collision probabilities in geometries more general than regular arrays, the present authors extend this work to cluster-type fuel elements. The basic procedure is the same as in the work referred to above. An analytic expression for the fuel-to-fuel collision probability is derived using arguments about its behavior in the black and white limits (i.e. in the limits of high and low cross sections). The Dancoff factor is derived from the behavior in the black limit. It is shown, by comparison with exact calculations, that for two types of cluster geometry of current interest in fuel element design, the proposed Dancoff factor is in error by at most 2%. Improved equivalence relations for cluster geometry are also considered. It has been customary to assume that the cluster is equivalent to an isolated rod of diameter dp/Γ, where dp is the diameter of a single pin in the cluster and Γ is the Dancoff factor. Such a procedure implies that the Bell factor of the cluster is constant and equal to its value for an isolated rod. It is shown in this paper that the Bell factor is a function of coolant density and that, in a particular case, the cluster is almost equivalent to an isolated rod at low density. As the density increases, the Bell factor drops rapidly by 6% and then increases slowly.
