NewburyportNews.com, Newburyport, MA

November 21, 2012

Hearing planned to address concrete problems

staff reports
Newburyport Daily News

---- — SEABROOK — The Nuclear Regulatory Commission is hosting a meeting that will update the public on the status of degrading concrete in the Seabrook nuclear power plant, and what the plant owners need to do to meet the NRC’s demands.

The public hearing will be held Dec.11 at One Liberty Lane Conference Center, 1 Liberty Lane, Hampton, N.H. It starts with an open house at 5:30 p.m., followed by the NRC’s official meeting and hearing at 7 p.m. The public is invited to attend.

The degraded concrete, which has been found in some of the lowest subterranean portions of the plant, has become a major concern for the NRC as the plant seeks to have its operating license extended an extra 20 years, to 2050. The NRC has said it will not extend the license until the plant owners demonstrate that the problem is being adequately addressed. The plant will also have to clear other hurdles before a license is issued, but the concrete problem is considered to be a unique circumstance.

Neil Sheehan, regional spokesman for the NRC, noted that several months ago the plant received a “confirmation action letter” spelling out actions it must take.

“We’re still looking at what they did in response to that,” Sheehan said. “We are by no means done with our work on the concrete degradation issues.”

NextEra, the company that owns the plant, has been working on a number of solutions to halt the problem. They will be discussed in detail at the meeting.

The meeting will have several experts from the NRC, including staff that has been assigned specifically to investigate Seabrook’s concrete problem. Called Alkali-Silica Reaction, or ASR, it occurs when groundwater infiltrates concrete and causes it to crack and crumble.

Sheehan said the most degraded areas exist in the lowest of the two underground tunnels that house electrical wires connecting the control building to the rest of the plant. The tunnel is about 40 feet below ground level.

The two electrical tunnels are identical and are part of the plant’s redundant safety design. If one electrical tunnel is inoperable, the other is fully capable of running the plant’s functions.

Initial testing of the affected area in Seabrook Station indicated a 22 percent loss of the compressive strength of the concrete in the ASR-involved areas only, but not in the support capacity of the walls themselves. The walls contain steel reinforcement bars that bolster their strength.

Sheehan said no other incidences of concrete degradation have been found in the plant in the past few months.

The NRC has said numerous times that it considers the plant to be safe.