Oyster Creek Back Online After Latest Unplanned Shutdown

by Patricia A. Miller

The Oyster Creek Nuclear Generating Station was back to full power this morning, more than a week after the plant shut down due to a problem with an electrical monitoring system, Exelon spokesperson Suzanne D’Ambrosio said.

The plant went back on line at 6:50 a.m. on Friday morning. It automatically shut down on May 7, when monitors detected an ”electrical disturbance” on the non-nuclear side of the plant, she said.

“The monitoring system was modified, inspected and tested before operators returned the

unit to service,” D’Ambrosio said. ”Residential energy supply was not affected by the brief outage.”

Oyster Creek’s latest problem came little more than two weeks after the federal Nuclear Regulatory Commission announced that it would ramp up scrutiny and conduct additional inspections at the plant after the discovery of past problems with electromatic relief valves, which help keep the reactor fuel covered and cool during a plant shutdown.

The NRC also issued a ”yellow” classification about problems with the valves, which indicates ”substantial safety significance.” The federal agency also issued a ”white” inspection finding - of low to moderate safety significance - dealing with the maintenance of an emergency diesel generator at the plant in Lacey Township.

“These enforcement actions underscore the need for plant owners to be vigilant when it comes to maintaining essential safety equipment,” NRC Region I Administrator Dan Dorman said on April 28. “In the case of these issues, two components that can play an important role during a reactor shutdown either experienced or may have experienced material failures that could have prevented them from performing their functions when needed.”

Oyster Creek was already under additional NRC oversight in 2014 because of a “White” (low to moderate safety significance) performance indicator that stemmed from four unplanned shutdowns, or scrams, in 2013 and 2014.

The NRC ’s performance indicator for unplanned scrams for each 7,000 hours of operation changes from green to white if a nuclear plant has more than three unplanned shutdowns. Oyster Creek crossed the green/white threshold on July 11, 2014, when the plant had a fourth unplanned shutdown, the NRC has said.

Oyster Creek is the oldest nuclear plant in the United States. It went online on Dec. 23, 1969.