Florida Power & Light made major safety modifications to its St. Lucie 2 nuclear plant without proper federal and public review, the Southern Alliance for Clean Energy said Tuesday. The facility continues to show alarming steam generator problems.
In a filing late Monday with the U.S. Nuclear Regulatory Commission, the Tennessee environmental group argues that documents show FPL made a "substantially changed safety design" of the facility's steam generators when the units were replaced in 2007 without public hearings and NRC approval, as required.
FPL, for instance, installed supports in the plant's steam generators that the utility initially told federal regulators it would not use because of safety concerns, the Southern Alliance said during a media teleconference Tuesday.
In addition, FPL used steam generators without what are called "stay cylinders," and in their places installed tubes to generate more power. Two California reactors had their stay cylinders removed and replaced with more tubes, which the Southern Alliance and other critics say contributed to steam generator problems that led to the permanent shutdown of the plants last year.
In February, the Tampa Bay Times first reported on the unusual tube wear problem at St. Lucie 2, a plant that came online in 1983 about 50 miles north of West Palm Beach. The article documented that the plant had the highest incidence of tube wear of any active nuclear plant in the country.
Each of St. Lucie 2's steam generators contain about 9,000 alloy tubes that help transfer heat and keep the reactor cool.
From 2007 through 2012, St. Lucie 2's steam generator tubes had sustained more than 11,000 dents and worn spots, far more wear than nearly every other plant with new steam generators. Some plants across the country with replacement steam generators have shown no signs of wear at all.
St. Lucie 2's wear is the result of the tubes vibrating and hitting against antivibration bars. Though federal regulators say the problem poses no safety concern, the unusual wear could shorten the life of the steam generators and cost hundreds of millions of dollars to replace, if the generators don't last until 2043 as intended.
FPL took the plant offline for a planned refueling outage and inspection of the tubes in March. The reactor returned to service about two months after the outage began and after sustaining damage from errant metal from a suspected tool found inside the steam generator.
Stephen Smith, Southern Alliance's executive director, said St. Lucie 2's sister reactor, Unit 1, did not have the same kinds of modifications to the steam generators and has had no problems.
"They followed the book at St. Lucie 1," Smith said. "St. Lucie 1 is not having problems. They are having unprecedented damage (at St. Lucie 2) because of the fact that they didn't follow proper procedures."
FPL spent about $146 million replacing the steam generators at St. Lucie 2 in 2007 and $600 million increasing the plant's power.
Michael Waldron, an FPL spokesman, said all of the issues regarding St. Lucie 2 have been thoroughly vetted by federal regulators and independent experts. He said the Southern Alliance, a regular fixture before state regulators in utility matters, simply continues to push an "antinuclear" agenda. "This is simply a willful misrepresentation of the facts designed to achieve a political objective,'' he said.
"There are neither tube integrity issues nor tube-to-tube wear," he said. "The rate of wear is less than we predicted it would be after this operating cycle. … There continues to be plenty of safety and operational margin."
FPL has yet to release its inspection report of the steam generator tubes. Federal regulators give utilities up to six months after the inspection to file the report.
The Southern Alliance is asking the NRC to hold public hearings on St. Lucie 2. Joey Ledford, an NRC spokesman, said: "The NRC will review any new information to ensure that the plant continues to meet the agency's requirements."
Ivan Penn can be reached at firstname.lastname@example.org or (727) 892-2332.