SEABROOK, N.H. — A Nuclear Regulatory Commission report detailing the results of an inspection of the concrete degradation at NextEra Energy Seabrook indicates the nuclear power plant’s staff is taking the needed steps to ensure structural integrity and operability, as it continues to delve into the problem.
The report details the findings of a recent three-week on-site inspection by agency regulators, according to NRC Division 1 spokesman Neil Sheehan, as well as four months of in-office reviews to assess the adequacy of actions taken by NextEra to address the plant’s alkali-silica reaction issues. Discovered in June 2009 in some of the 2-foot thick walls of the plant’s subterranean tunnels, ASR is a slow chemical reaction that can happen when moisture interacts over a long period of time with the alkaline cement and reactive silica found in some aggregates used to make concrete. ASR forms a gel that expands, causing micro-cracks that affect concrete properties, but which can take five to 15 years to show up.
While repeatedly assuring the public that Seabrook Station is safe, the NRC has stated it will make no final decision on NextEra Energy Seabrook’s request for a 20-year extension of its operating license until the commission is satisfied that all its concerns have been addressed and is assured the plant can continue to operate safely. The results of the inspection will be the topic of discussion on Tuesday, when the NRC holds a meeting in nearby Hampton to update the public on the ASR situation at Seabrook Station. While Cape Ann is not included in the 10-mile evauation zone in the event of a Seabrook reactor failure or other emergency, the plant sits just 17 miles as the seagull flies across the water from Rockport’s Halibut State Park, and is visible on a clear day from there or from Gloucester’s Folly Cove and parts of Lanesville. The NRC issued a Confirmation Action Letter in May listing actions the plant will take in regard to monitoring the current ASR conditions. That includes a lengthy analysis currently being done by the University of Texas to evaluate ASR’s possible future impact on the structure’s physical integrity. That study is expected to continue into mid-2014.