As workers and responders conducted a drill at Ginna nuclear power plant, a real situation arose at the Wayne County facility and it unexpectedly shut down when the generator went off-line during a test.
The generator problem triggered an automatic response that led to control rods inserting into the reactor at the 43-year-old plant in the town of Ontario, halting the nuclear reaction that creates the heat and steam used to generate electricity, said Neil Sheehan, a spokesman for U.S. Nuclear Regulatory Commission (NRC).
“All safety systems functioned as designed and there were no complications,” Sheehan said. “We don’t have any reports of damage at this point.”
Maria Hudson, a spokeswoman for plant owner Constellation Energy Nuclear Group, said the reactor shut down at 2:20 p.m. Wednesday. Plant workers were still searching for a cause of the generator problem in late afternoon.
“It’s an unfortunate thing but it’s not anything would cause any public concern,” she said.
Sheehan and Hudson said the plant was in “hot shutdown” mode, meaning the reactor and related systems remain heated and pressurized. That is an intermediate stage from which it is possible to return to service relatively quickly should that be prescribed — as opposed to a full cold shutdown, a stage from which it takes hours of ramping up before the plant can resume generating electricity again.
Hudson said late Wednesday afternoon she did not know if Ginna would proceed to cold shutdown.
Sheehan, who said an NRC on-site inspector arrived in the Ginna control room not long after the incident, said there was no immediate estimate of when the plant could return to full service.
The incident took place during one of the periodic mandatory and voluntary drills conducted by plant workers and outside responders to prepare for plant malfunctions, intrusion by outsiders, storms and other events that could compromise plant safety.