The Nuclear Regulatory Commission on Wednesday accepted NextEra Energy Resources’ license amendment request as the company addresses concrete degradation issues, known as alkali-silica reaction (ASR), that have long plagued the Seabrook Station Nuclear Power Plant in New Hampshire.
The NRC can now conduct a detailed technical review of the application. Agency spokesman Neil Sheehan stated by email Friday that the review is expected to take about 22 months to complete, setting a finish line for August 2018. Now that it has accepted the license amendment request, the NRC will allow interested parties the opportunity to request a hearing on the application, as well as open the application up for public comment.
Since 2013, lawmakers have hammered NextEra and the NRC on the concrete degradation issue, which has crept into the nuclear facility’s foundation and vertical structures, including the containment building, which houses the plant’s nuclear reactor. The NRC has maintained that the 26-year-old facility is “degraded but operable.”
The license amendment request was filed for Seabrook Unit 1, and it would alter the plant’s updated final safety analysis report to better address the concrete issue. The NRC responded that NextEra’s filing lacked the detail needed for the regulator to carry out its review, so the company filed a package of supplemental information on Sept. 30.
In the supplement, NextEra provided the following information: the technical basis for testing correlation between concrete elastic modulus and through-thickness expansion; information on the company’s alkali-silica reaction deformation assessment program; and information on how concrete backfill may apply pressure to adjacent structures.
Massachusetts lawmakers – state Sens. Kathleen O’Connor Ives (D) and Daniel Wolf (D), and state Reps. Ann-Margaret Ferrante (D) and James Kelcourse (R) – penned a letter in May asking the NRC to withdraw NextEra’s operating license at Seabrook, calling the facility “an unacceptable threat” to the 4 million New Englanders living within 50 miles of the plant. The lawmakers maintain that the NRC does not have a firm grasp on the degradation issue. The regulator has acknowledged that “much work needs to be done” on the matter.
In its supplemental package, NextEra provided a building deformation assessment for Seabrook’s containment enclosure structure. The company referred to it as a “stage 3” deformation evaluation, which is the most complex of the three deformation stages.
“The process of evaluating each structure at Seabrook Station for deformation is ongoing,” the filing reads. “The process has initially focused on evaluating the structures with higher levels of observed deformation, higher ASR expansion measurements, and structures with low margin to structural design code acceptance limits. Because the process of analyzing all structures is ongoing, examples of structures that have been dispositioned using only a Stage One Screening Evaluation are not currently available.”
Additionally, NextEra provided an explanation on how it plans to address pressure in concrete structures created from concrete backfill. The company also drew up an outline for how it plans to address its alkali-silica reaction program. NextEra’s approach includes: review, acquisition, and assessment of deformation data; quantitative assessment of ASR demands; analysis of ASR-impacted structure; and establishment of monitoring threshold limits.
