By Angeljean Chiaramida
---- — HAMPTON, N.H. — A representative of nuclear watchdog group C-10 urged the Nuclear Regulatory Commission this week not to allow any “short cuts” concerning the alkali-silica reaction concrete degradation problem at the NextEra Energy Seabrook nuclear power plant.
C-10 staff member Debbie Grinnell said the situation at Seabrook Startion has to be investigated thoroughly to ensure its safety not only until 2050 — when an extended operating license that the plant has requested would expire — but now.
“As Seabrook (Station) is the first in the nuclear industry to demonstrate extensive and marked ASR concrete degradation and the NRC had no technical or regulatory basis for ASR, the NRC must require a comprehensive extent of condition on all of Seabrook (Station’s) buildings and structures with actual, not virtual, data from concrete at Seabrook (Station) using appropriate acceptance criteria ... ,” Grinnell told the panel.
Grinnell was among 120 area residents and members of watchdog groups who turned out for an information session Tuesday night organized by the NRC to offer an update on the status of the ASR problem, which was discovered two years ago on areas of several subterranean cement walls at Seabrook Station, as well as details of the most recent inspection of the plant.
Alkali-silica reaction is a slow chemical reaction that can occur when moisture is present and causes an interaction between the alkaline cement and reactive silica found in some aggregates used to make concrete. ASR forms a gel that expands, causing micro-cracks that affect concrete properties, but which can take five to 15 years to show up. The aggregate used when Seabrook Station was built has been discovered to be vulnerable to ASR.
Although ASR is commonly found in dams and transportation structures like bridges, roads and airport runways where it has been successfully mitigated, Seabrook Station is the first nuclear power plant in the U.S. to discover and report the presence of ASR.
The ASR problem, which came to light on the heels of Seabrook Station’s announcement that it was seeking to extend its operating license by an additional 20 years, sparked immediate controversy.
Many of Seabrook Station’s opponents turned out Tuesday night to question not only the status of the ASR and the plant’s safety, but also the NRC’s handling of the situation.
NRC officials ensured that in spite of the ASR, Seabrook Station is structurally sound and well within its physical margins to operate safely. The NRC has repeatedly confirmed the plant is safe, but Tuesday’s update came after the issuance of a lengthy report following a recent substantial review of the situation, which included a three-week on-site inspection.
Newburyport resident Bruce Skud of No More Fukushimas told the NRC officials that although he was “thrilled” to hear that the recent inspection showed Seabrook Station is safe, he found himself quite angry with the agency for not shutting down the plant when the problem was first discovered in the late summer of 2010.
Christopher Miller, director of the NRC’s division of reactor safety, assured Skud that there had been a number of reviews of the situation prior to the recent one. All those reviews determined the ASR-affected concrete at the plant retained its physical integrity and was assessed as operable but degraded, meaning the plant was safe.
For Herb Moyer of the Exeter, N.H.-based Seacoast Anti Pollution League, the problem refueled his long-held displeasure with having a nuclear power plant in Seabrook. Moyer told NRC officials he’d been fighting the plant since 1969, when its construction was first floated. He opposed the approval of the plant’s first operating license, he said, and is now fighting the approval of the extension.
Moyer, a teacher at Winnacunnet High School in Hampton when the plant was under construction during the 1980s, said stories he heard from his students at the time made him worry there could be future problems with the concrete at the plant. Moyer said his students recounted parties they had near the plant where they tossed empty beer bottles into the concrete.
During the presentation, NRC senior project manager Richard Cook said that most of the concrete walls at Seabrook Station are 2 feet thick, with a tight lattice of 2-inch thick reinforcing steel bars within the walls. Cook, who led the team that recently inspected Seabrook Station’s ASR issue, said concrete provides compression strength for walls, while the web of steel reinforcing bars provides tensile strength.
There are two walls surrounding the nuclear reactor in the containment building, Cook said, a 4-foot-thick inner wall and an outer wall that’s 30 inches thick.
Although some spoke in support of NextEra Energy Seabrook at the meeting, most were there to ask questions about the ASR problem, according to NRC Region I spokesman Neil Sheehan. He added that the questions asked by those who spoke indicate they had “a good grasp” of the ASR issue.
To keep information flowing, the NRC has created a page on its website — www.nrc.gov/info-finder/reactor/seabrook/concrete-degradation.html — to consolidate information on the ASR situation at NextEra Energy Seabrook. Postings include slides from a 2012 public meeting on the topic with graphics illustrating the condition. The site will also carry all the related reports, letters and other documents concerning the ASR situation.
According to Miller, the site, which went live on Monday, is the NRC’s continued attempt to respond to the public’s desire for information on the problem.
Miller said the last inspection report is far from the end of the NRC’s attention to the situation at Seabrook Station. Another inspection is already scheduled for early 2013, he said, and NextEra is continuing to monitor the problem as well as research the possible future impact ASR could have on the structure through its project at the University of Texas.
The NRC has also put together an agency-wide team of experts on the topic as well as reached out to its foreign counterparts who have experienced ASR in their nuclear power plants in other countries.
Both Miller and Cook insisted the review of Seabrook Station’s ASR issue is ongoing because “there’s more that needs to be done” to determine the impact of degradation on the concrete structures there.
“More to be done by Seabrook Station,” Cook said. “And more to be done by the NRC.”