Pilgrim nuclear plant shut down after condenser problem

By Colin A. Young, Globe Correspondent

Power production at the Pilgrim Nuclear Power Station in Plymouth was halted this afternoon when a condenser at the station lost vacuum pressure during a cleaning, forcing operators to shut down the entire plant, officials said.

Operators shut down the plant, which was operating at about 30 percent power at the time, according to Neil Sheehan, a spokesman for the Nuclear Regulatory Commission. Plant operators initiated a manual “scram,” which “involves the control room operators inserting all of the control rods into the reactor core to halt the fissioning process,” according to Sheehan.

The condenser uses water from the bay to cool and convert into water the steam that was produced in the reactor and then used to spin the turbine to generate electricity, Sheehan said. The condenser operates in a vacuum to maximize efficiency, he said.

NRC inspectors at the plant “did not identify any safety concerns or performance issues,” Sheehan said. “They will follow the company’s efforts to troubleshoot the cause of the loss of condenser vacuum and any corrective actions.”

Rob Williams, a spokesman for Entergy Corp., the Louisiana-based company that has run the plant since 1999, said that the incident, which happened at 1:11 p.m., took the station off the power grid. The plant will remain shut down until investigators determine what caused the problem, Williams said.

“The technicians are now investigating the cause of that reduced condenser performance,” he said. “As we do with every shutdown, there will be a comprehensive investigation to look into what caused the condenser performance issue.”

Multiple failures by the control room staff at the station last spring sparked the power plant’s first emergency shutdown in years, according to a report released in September by the NRC, which issued a finding that the problems were likely serious enough to warrant a rigorous year-long review of the plant’s safety procedures.