Federal officials toured Seabrook Nuclear Power Plant Friday in preparation for a hearing on degrading concrete at the facility.
Seabrook is the only nuclear plant in the country known to have a chemical issue causing cracks in its concrete foundations.
Watchdog group C-10 alleges the plant's owner, Florida-based NextEra, hasn't adequately studied the problem. Nuclear regulators have repeatedly disagreed. They approved NextEra's monitoring plans for the cracks and granted Seabrook a license extension from 2030 to 2050 earlier this year.
Separately, an administrative law panel at the Nuclear Regulatory Commission will hold a hearing on the concrete issues in late September. As part of the case, they took a private tour of the plant Friday with representatives from C-10 and NextEra.
This fall's hearing will include a chance for public input on Sept. 23. The proceeding could result in changes to plant operations. Seabrook is now one of two nuclear plants left on the New England grid, along with Millstone Station in Connecticut. That's after Pilgrim Station, in Massachusetts, closed last month.
Nuclear power makes up roughly a third of the region’s fuel mix at any given time, second only to natural gas.