Excerpts from the Globe’s environmental blog.
US Representative Edward J. Markey wants the Nuclear Regulatory Commission to deny Seabrook Station and other nuclear power plants license extensions if they are requested too early in the plant’s operating life.
In a letter sent to the NRC’s chairman, Greg Jaczko, Markey, a Massachusetts Democrat, noted that inspections at Seabrook uncovered structural weaknesses in concrete surrounding a safety-related tunnel only two decades into the plant’s 40-year license.
Seabrook applied for relicensing last year and is hoping to receive approval soon to operate another two decades. Its license expires in 2030.
“If safety structures that are supposed to help cool the Seabrook nuclear power plant are experiencing such alarming degradation during the reactor’s ‘adolescence,’ there is simply no way that the NRC can guarantee that it will remain safe until it enters its ‘golden years’ almost 40 years from now,’’ Markey wrote.
The letter was also signed by another Democratic congressman, John Tierney, also of Massachusetts.
The NRC allows plants to apply for relicensing up to 20 years before their 40-year licenses expire. That gives the commission at least two decades of plant history to consider. Spokesman Neil Sheehan also noted that it can take years to receive a license extension, which is “why we urge plant owners to apply with at least five years remaining’’ on a license.
Seabrook’s owner, NextEra Energy Resources, said it is not requesting relicensing too early.
“License renewal approval at this stage of Seabrook Station’s operating life will allow us to do the very best job possible planning our maintenance activities and expending funds for new equipment and systems to ensure that our plant is in top condition at the end of our original license period and fully ready for an additional 20 years of safe and reliable operation,’’ spokesman Al Griffith said in a statement.
Construction began on Seabrook in the 1970s but lawsuits, public opposition, and other problems delayed it from ramping up to full power until 1990. It received a 40-year license in 1986; that was later extended by more than three years to reflect a testing period when it operated at low power.
Many plants have had licenses extended, but critics say the aging plants are becoming increasingly compromised.
Seabrook and other plants have come under increasing scrutiny since the earthquake and tsunami in Japan caused a nuclear crisis.
Last week, an NRC inspection report noted that concrete surrounding an electric tunnel at Seabrook has lost almost 22 percent of its strength because it has been saturated with groundwater for more than a decade.
The problem, reported by NextEra last year, is believed to be the first confirmed instance of such degradation in a safety-related concrete structure at a US nuclear plant. Still, the NRC said it found no effect on electrical systems, piping, or any other components.
The concrete walls are performing well above design specifications, it said.
Markey’s office says that since 2009, the NRC has begun license renewal applications for eight reactors more than 10 years before their current operating licenses expire — and some for almost 20 years.
Markey and Tierney said there is little reason for such early consideration. There are exceptions: the Pilgrim nuclear plant has been waiting since January 2006 to renew its 40-year license before it expires next year.