The Nuclear Regulatory Commission (NRC) said on Sept. 2 that it was increasing its oversight of the Pilgrim Nuclear Power Plant as a result of an inspection finding stemming from an unplanned shutdown in January. The action moves the plant into the Repetitive Degraded Cornerstone Column, indicating multiple problems in meeting one of the NRC’s plant performance criteria.

“The most recent finding highlights the continuing weaknesses in the implementation of Entergy’s program for identifying, evaluating and resolving problems at Pilgrim,” NRC Region I Administrator Dan Dorman said. “Our increased oversight will focus on understanding the reasons for those weaknesses and the actions needed to achieve sustained improvements.”

Repeated Failures

The January 2015 shutdown occurred during a blizzard when the plant was forced offline after two distribution lines failed. Several hours after the shutdown, the plant reported a failure of the high-pressure coolant injection system due to an equipment malfunction. The incident came on the heels of similar problems during 2013.

Entergy’s repeated inability to correct the plant’s problems led to the downgrade, the NRC said.

According to the statement announcing the decision, the finding stemmed from performance of the plant’s safety relief valves during the January 2015 event. The NRC noted that Entergy could have prevented the problem, “if it had properly identified, evaluated and corrected a condition that caused one of the valves to fail to operate correctly after a plant shutdown on Feb. 9, 2013. This failure to identify and correct the valve condition also constituted a violation of NRC requirements.”

The move came a little more than a week after another unplanned shutdown on Aug. 22. That event reportedly resulted when a broken air-nitrogen line caused a main steam isolation valve to close.

Official Alarm

The NRC announcement alarmed officials in Massachusetts and prompted Gov. Charlie Baker to send a letter to Entergy demanding that the company correct the underlying problems. Baker urged Entergy to “take all steps necessary to perform an appropriate root cause analysis of the shutdowns and to complete all necessary repairs and corrective actions.”

U.S. Sen. Edward Markey (D-Mass.), a long-time foe of the nuclear industry and Pilgrim in particular, was more blunt.

“Pilgrim has had long-standing and repetitive safety problems and unplanned shutdowns that require this increased level of NRC oversight, especially since it is the same design as the reactors that melted down during the Fukushima nuclear disaster,” he said in a statement. “NRC must continue this aggressive oversight until Entergy can prove unequivocally that it has dedicated the resources, manpower and training to guarantee the safe and secure operation of this reactor.

An Entergy statement said the company would “review the details of the NRC’s decision to consider what actions we need to take to enable Pilgrim Station to return to normal NRC oversight.”

Pilgrim joins Arkansas Nuclear One—also owned by Entergy—as the only plants in the Repetitive Degraded Cornerstone Column.

—Thomas W. Overton, JD is a POWER associate editor.