SEABROOK — The Nuclear Regulatory Commission will hold a public meeting next month to discuss the testing program related to the alkali-silica reaction concrete problem at the NextEra Energy Seabrook nuclear power plant. The meeting will be held on Oct. 9 at 6 p.m. at the Inn at Hampton in Hampton, N.H.
In June 2009, staff at Seabrook Station reported to the NRC the discovery of areas of alkali-silica reaction in some subterranean concrete walls at the power plant, such as the area of an electrical tunnel that holds wiring. Alkali-silica reaction, or ASR, is a slow chemical reaction between the alkaline cement and reactive silica found in some aggregates used to make concrete.
The phenomenon can occur when moisture is present and is commonly found in dams and structures like highways and bridges. ASR forms a gel that expands, causing micro-cracks that can affect concrete properties. It can take five to 15 years to show up.
The NRC has continually assured the public that this problem does not impact the safety of Seabrook Station and that affected walls still meet federal standards for load-bearing capacity. Primarily in locations below ground, ASR-affected areas are in 2-foot-thick walls reinforced with a lattice of steel rebar that allows the walls to maintain their physical integrity currently, according to NRC reports.
The new finding, however, caused significant controversy among anti-nuclear advocates, as well as state and federal officials when NextEra filed an application with the NRC requesting a 20-year extension from 2030 to 2050 of Seabrook Station’s operating license.
Worries grew after a March 2011 magnitude-9 earthquake rocked the East Coast of Honshu, Japan. The quake, and the tsunami that followed, devastated the area. The resulting loss of electrical and backup power resulting from the combined disasters caused the meltdowns of three of the nuclear cores at the region’s Fukushima Daiichi nuclear power complex. The event caused many to raise concerns as to the seismic stability of U.S. power plants, leading the NRC to take related action within the nation’s nuclear industry.