Inspectors from the U.S. Nuclear Regulatory Commission (NRC) found deterioration of concrete in below ground-level structures at the 1,245 MW Seabrook nuclear power plant in New Hampshire, according to Seacoast online.
The inspectors discovered groundwater infiltration, calcium carbonate deposits, corroded steel supports, base plates and piping, corroded anchor bolts, pooling of water and a 21.7 percent reduction in the compressive strength of the concrete, according to a May 23 NRC report. The inspections are part of the review to extend the plant’s operating license until 2050.
A plant spokesperson was quoted as saying that plant officials have been dealing with and controlling the groundwater infiltration for years and that parent company NextEra notified the NRC about the problem.
Two “non-cited violations” NRC inspectors found during the plant's annual review earlier this year and mentioned in a May 12 agency letter to plant officials reportedly had to do with how NextEra handles reviews of concrete deterioration and alleged inadequate monitoring of the plant’s intake and discharge transition structures.
The NRC considered both violations as very low (green) level because the issues were not design or qualification deficiencies, did not result in an actual loss of safety function, did not represent a loss of barrier function and were not potentially risk-significant for external events, according to the May 12 letter.
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