HAMPTON — Officials with the Nuclear Regulatory Commission were back in the area Wednesday night to continue discussions about concrete degradation at Seabrook nuclear power plant caused by Alkali-Silica Reaction, or ASR.
Although ASR is not uncommon in other concrete infrastructure, it is the first time it has been discovered in a United States nuclear power plant, and has raised safety concerns among many in the community who spoke out at Wednesday's meeting.
NextEra Energy, owner and operator of Seabrook station, first notified the NRC of the ASR issue in 2010 and the regulatory agency has been reviewing their short and long term plans for addressing the issue, and determining how it could impact the plant into the future.
This is of particular importance as NextEra Energy pursues a 20-year license renewal for the plant. The current license expires in 2030.
On Wednesday, NRC officials heard a presentation from University of Texas-Austin professor Oguzhan Bayrak who is leading a long-term study at the Ferguson Structural Engineering Lab on how ASR could impact concrete.
The study has been commissioned by and is being paid for by NextEra Energy.
David Lew, deputy regional administrator of the NRC's Region 1 office, said they believe NextEra has demonstrated that safety-related structures at the plant remain operable and safe.
He added that no regulatory decision will be made on Seabrook's license renewal until the NRC feels confident about their long-term plans for addressing ASR.
All license renewals and new licenses are currently on hold anyway pending a Waste Confidence Decision from the Department of Energy regarding what to do with the nation's nuclear waste.
In addition to the testing being done in Texas, back in Seabrook, work to monitor ASR includes core boring, crack indexes and petrographic analysis.
The long-term testing being done in Texas focuses on the integrity of anchors in the contract, one-way shear strength, and rebar anchorage.
Bayrak said in tests done so far testing anchor strength, they saw similar load bearing capacities with low levels of ASR degradation as in control tests in terms of performance.
Concrete wall segments, beams and blocks are being conditioned in a sort of greenhouse to try and make the ASR happen at a faster rate.
Bayrak said they created a concrete that closely mimics that used in the initial construction at Seabrook, but can generate ASR much faster. Some in the audience do not feel that is good enough, and questioned why they were not using concrete from the unused unit two structure that sits unused. NextEra officials said there are technical and practical problems with using that concrete, which is why they chose not to, but did not go into detail.
The testing was originally scheduled to be completed in 2014 but Bayrak said it may go into 2015.
New Hampshire State Representative Peter Schmidt was one of few residents from the Granite State who spoke during the forum. He said it seems at least incredibly premature to think about extending Seabrook's license at this point.
The vast majority of those who spoke at the meeting hailed from coastal towns in Massachusetts that lie within the evacuation zone, including Newburyport, Newbury and Amesbury, and most asked that the plant not be re-licensed. Some even said it should be shut down today until the ASR issue is better understood.
David Wright with the Union of Concerned Scientists said they have some concerns about the integrity of the testing being done in Texas and the inspection process at Seabrook.
For now, the NRC will continue an ongoing structures monitoring program on site and will be visiting Texas to conduct independent monitoring and inspections there as well.