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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.
Dong H. Nguyen, Lawrence M. Grossman
Nuclear Science and Engineering | Volume 30 | Number 2 | November 1967 | Pages 233-241
Technical Paper | doi.org/10.13182/NSE67-A17334
Articles are hosted by Taylor and Francis Online.
The space-dependent ion production rate by fission fragments escaping from a fuel plate is studied using: 1) the Bohr stopping equation with the Thomas-Fermi approximation of the effective charge Zeff; 2) the Alexander-Gazdik (A-G) semiempirical velocity-distance relationship for fission fragments. The assumptions are: a) no scattering during slowing down; b) the nonionizing energy loss in nuclear recoils can be taken into account by increasing the w value for fission fragments over that for α particles; c) a delta-function mass distribution for the light and heavy group; and d) a monoenergetic source. The energy current carried by the fragments at a point in the outer medium is first derived, and the energy deposition per unit volume per second is obtained by taking the gradient of the energy current. Dividing the energy deposition by the w value for the medium yields the ion production rate by fission fragments in that medium. The results show that the semiempirical velocity-distance relationship gives a higher ion production rate than that given by the velocity-distance relationship derived from the Bohr stopping equation with the Thomas-Fermi approximation of the effective charge Zeff. The volumetric, spatial average ion production rate is also obtained. For a fuel plate containing 20% 235U and 80% Pt and for a flux of 6 × 1010 n/(cm2 sec), the velocity-distance relationship based on the Bohr stopping equation gives an average ion production rate of 2.0 × 1013 ion pairs/(cm3 sec) in a mixture Ne + 0.1% Ag. Using the same values for the fragment ranges, the semiempirical velocity-distance relationship yields an average volumetric ion production rate in neon higher by about 18% for the light fragment and by about 20% for the heavy fragment. According to existing experimental results on plasmas induced by fission fragments, an ion source of 2.0 × 1013 ion pairs/(cm3 sec) would yield a conductivity of about 1 × 10−3 (Ωm)−1 in the gas mixture Ne + 0.1% Ag, at 200-mm Hg and 400 °K and at an electric field of 560V/m.
