WASHINGTON — Owners of at least two dozen nuclear reactors across the United States, including the operator of Indian Point 2, in Buchanan, N.Y., have told the Nuclear Regulatory Commission that they cannot show that their reactors would withstand the most severe earthquake that revised estimates say they might face, according to industry experts.
As a result, the reactors’ owners will be required to undertake extensive analyses of their structures and components. Those are generally sturdier than assumed in licensing documents, but owners of some plants may be forced to make physical changes, and are likely to spend about $5 million each just for the analysis.
Indian Point 2 and 3, in Westchester County on the east bank of the Hudson River about 24 miles from the Bronx border, are nearly identical. But the plants were previously owned by two different entities — Consolidated Edison and the New York Power Authority — and were analyzed separately over the years. Entergy says it believes the commission will accept Unit 3 as it is.
The earthquake reassessment has been a mixed bag; it showed that in many locations, the chance of an earthquake in which the ground shakes relatively slowly — the most damaging kind — was smaller than previously estimated. High-frequency earthquakes, in which the shaking back and forth happens more than 10 times per second, was higher for some locations. Those high-frequency quakes do not threaten big components, but some engineers say they can cause electric switches to change position, among other problems.
A second Entergy plant, Pilgrim, in Plymouth, Mass., will also require more analysis, Mr. Drake said. Two industry experts said that across the central and eastern United States, plants at 24 sites reported that the new earthquake threat was larger than what they were designed to face. The commission has not released a total yet.
But Scott Burnell, a spokesman for the commission, said many reactors fell into that category, so many that there were not enough engineers to analyze them all simultaneously. The commission will group them in priority, he said.
Read more at Under Revised Quake Estimates, Dozens of Nuclear Reactors Face Costly Safety Analyses