In October 2009, contractors cut into the containment building at the Crystal River nuclear power plant in Florida, in order to replace aging steam generators. The containment building cracked and began to fall apart during the operation. Work ceased, and the reactor has been shut down since that time.
Now, Progress Energy, owners of the plant, have attempted to pass the costs of repairs, now estimated at $2.5 billion, to its customers, arguing that they didn’t know that the procedure used was untested and unsafe.
An investigation by the St. Petersburg Times says that the company had warning about the dangers involved. Charles Hovey, an experienced construction foreman who at worked on similar projects at other nuclear power plants, sent a series of e-mails to Progress. According to the Times, one of the e-mails warned:
“I have never heard of it being done like this before and I just want to express my concerns to you one last time.”
Hovey’s concerns had to do with the number and order of “tendons” Progress intended to loosen in the procedure. Tendons are metal rods inside the concrete designed to reinforce the structure.
According to the Times:
Hovey’s concerns centered on how many tendons Progress planned to loosen and in what order.
At other nuclear plants, engineers usually loosened 70 to 80 tendons.
Progress hired Sargent & Lundy to determine how many tendons on which to focus. The company had never performed such an analysis for a nuclear containment wall, according to documents obtained by the St. Petersburg Times. The engineering firm first recommended 97.
Too many, Progress said.
“We said, ‘Hey, that’s a lot of tendons,’ ” John Holliday, a contract employee for Progress in charge of the work on the containment building, recalled in a recent deposition. “Can you go back and take another look at this?”
The next proposal: 74, within the range loosened at other plants.
Holliday wasn’t satisfied. “De-tensioning the tendons is a very expensive and time-consuming effort,” he said.
The engineers were told “to put on their thinking caps and determine if there is an alternative method of analysis that we could pursue that would result in a lot less tendons being de-tensioned,” Holliday said.
The final result: 65 tendons would be loosened.
The work did not go well:
In October 2009, Mac & Mac Hydrodemolition cut into the containment building. Holliday noticed a break in the concrete but decided to continue, thinking it predated the ongoing work.
An hour later, water began pouring through the wall. And the scene was not like what they had imagined.
“Hydro-demolition resulted not in the small pieces (you) would expect, (but) big chunks falling off the wall,” Holliday told analysts from Performance Improvement International.
PII concluded that the tendon de-tensioning, particularly the sequence Progress used, and removal of the concrete caused the building to crack.
“A primary factor was the number of de-tensioned tendons that were located in a row,” the analysts noted in their report.
Hovey’s was not the only warning Progress received:
“Why are we doing tendons different here than all other jobs?” site supervisor John Marshall asked in an e-mail sent to Sam Franks, another Bechtel supervisor.
Gary Goetsch, a supervisor with the company hired to prepare the containment building for cutting, had worked on 11 similar jobs. He said the Crystal River job was “the first and only one” to use the procedure adopted by Progress officials, according to notes of his interview with analysts from Performance Improvement International, the firm hired by Progress to determine what went wrong.
Link: http://www.tampabay.com/news/progress-was-warned-about-cutting-into-nuclear-plant-building/1200304
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