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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.
Min Lee, Jiing-Huae Wu
Nuclear Technology | Volume 98 | Number 3 | June 1992 | Pages 289-306
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34660
Articles are hosted by Taylor and Francis Online.
Operators need to initiate feed-and-bleed (F&B) cooling to depressurize and cool down the reactor coolant system (RCS) of a pressurized water reactor (PWR) in the event of a loss of all feedwater. Long-term responses of the RCS and containment of a PWR in the loss-of-all-feedwater event with and without F&B cooling are analyzed with the Modular Accident Analysis Program (MAAP) computer code. Results of the MAAP analyses are compared with those from the RELAP5/MOD2 code. Results of the MAAP analyses show that the execution of F&B cooling at 48 min, as the steam generator secondary-side water level reaches a 6%-wide range, could depressurize the RCS along the coolant saturation curve with an average cooldown rate of 13 K/h. The conditions of the RCS reach the entry point of the residual heat removal system at ∼7 h. The RCS could still be depressurized if the execution of the F&B cooling operation is delayed to 70 and 100 min, i.e., ∼6 min after steam generator secondary-side dryout and 2 min after core uncovery, respectively. The average RCS cooldown rate, however, is above the limit specified in the technical specifications. Delaying execution of F&B cooling to 133 min can still depressurize the RCS. That, however, is too late to prevent the core from melting. Plant characteristics that are important for the responses of the RCS to F&B cooling are the flow capacity and the setpoints of the pressurizer power-operated relief valves, the flow rate, and the shutoff head of the high-head safety injection system. Results of the MAAP calculations need to be interpreted carefully because of the simplified nature of the MAAP code. Benchmark exercises of the MAAP input deck against the sophisticated system analysis code are essential for the validity of the MAAP results.