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San Onofre Nuclear Generating Station
Tubes inside a new steam generator at San Onofre Nuclear Generating Station are showing unusual and potentially dangerous signs of deterioration, federal regulators announced on Thursday.
"The amount of wear that we are seeing on these tubes is unusual for a new steam generator," said Nuclear Regulatory Commission spokesman Victor Dricks.
More than 800 tubes of the San Diego County plant showed a 10 percent thinning in the tube wall, officials said. 69 others had at least 20 percent thinning. And two tubes needed to be plugged and taken out of service because a third of the wall was worn away.
"If you have that kind of thinning anywhere along the length of the tube, you have a problem because it degrades the integrity of the tube, which can contribute to leaks," explained Dricks.
Safety implications could be "very severe," warned Joram Hopenfeld, a retired NRC engineer and researcher, as the tubes are one of the primary barriers to radioactivity