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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.
Ivars Neretnieks
Nuclear Technology | Volume 71 | Number 2 | November 1985 | Pages 458-470
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT85-A33698
Articles are hosted by Taylor and Francis Online.
The diffusivities measured by various investigators of several species in compacted bentonite clay have been compiled and analyzed. Small anions diffuse slower than an uncharged molecule such as methane. Large anions move orders of magnitude slower still. The actinides thorium, uranium, plutonium, neptunium, and americium are considerably retarded by sorption effects. Their movement can be explained by pore diffusion with retardation. Cesium, strontium, and protactinium move considerably faster than can be explained by these effects. The faster mobility is probably due to surface migration. A simplified model is presented by which the importance of the backfill barrier in retarding the radionuclides can be assessed. It is based on the computation of the evolution of the concentration profile of the diffusing nuclide in the backfill. Using this model, the flow rate out from the backfill to the flowing water can be compared to the inflow into the backfill due to leaching. A second model treats nuclides with solubility limitations in a similar way. A diagram is presented where the maximum outflow or concentration of a nuclide from the backfill can be determined as a function of barrier thickness and nuclide diffusivity and decay constant. Using the experimentally obtained diffusivities, it is found that a 0.375-m-thick backfill will eventually let through practically all 129I, 99Tc, 226Ra, 231Pa, 234U, 235U, 238U, and 237Np. The maximum release rate for 137Cs, 90Sr, 239Pu, 240Pu, and 243Am will decrease by one to three orders of magnitude compared to the leach rate. Americium-241 will decay to insignificance in the backfill.
