As the decommissioning process continues at the San Onofre Nuclear Generating Station, a scenario similar to the one that led to the power plant’s demise is unfolding about halfway between Orlando and Miami.
In 2007, Florida Power & Light installed two new steam generators at its St. Lucie Nuclear Power Plant at a cost of $140 million (a fraction of the nearly $700 million spent at San Onofre). The new generators were supposed to remain in service until the reactor's scheduled retirement in 2043.
When the plant shut down in 2009 for maintenance and refueling, however, 2000 of the 18,000 metal tubes that compose the generators showed damage at over 5800 locations. Because each tube is 70 feet long, they may have abnormal wear or damage observed at more than one location.
The damage observed was at the time the worst on record for the nuclear industry — until a tube burst at San Onofre's Unit 3 generator, releasing a small amount of radiation into the atmosphere. Inspectors there found 10,284 damaged tubing sections along 1806 total damaged tubes. San Onofre's Unit 2 generator, which was shut down for maintenance at the time, was also inspected and found to be heavily damaged.
Florida Power & Light took a different approach than San Onofre operator Southern California Edison — they put the reactors back online and turned up the juice, generating even more power than before. In 2011, the Florida plant again shut down for maintenance and inspection; the damage was 46 percent more severe, with nearly 3000 tubes showing damage at over 8600 locations.
Officials at Florida Power & Light argue that their design should not be compared to San Onofre (St. Lucie's generators were supplied by the French firm AREVA; San Onofre's by Mitsubishi Heavy Industries), though that's exactly what Edison did during their ultimately unsuccessful attempt to gain permission to resume operations in San Diego. St. Lucie was identified as "the next closest plant with a high number of wear indications," according to a Tampa Bay Times report.
Power generation at St. Lucie has been bumped by another 12 percent since generators there were last inspected in November 2012. The next shutdown and inspection is scheduled for next month, when experts fear they could find even further deterioration in the steam generators that are hoped to last for another three decades.