Hurricane Sandy tests the U.S.'s nuclear facilities as New Jersey's Oyster Creek declares a rare "alert" while half a dozen other plants slow or shut down operations.
Oyster Creek—which is located on the coast of Barnegat Bay about 60 miles east of Philadelphia on the New Jersey Shore—is the country's oldest nuclear power plant. The facility was theatened yesterday after a disasterous combination of the rising tide, the direction of the wind and the tidal surge caused water levels to rise 6.5 feet above normal within the plant, according to a spokesman from the U.S. Nuclear Regulatory Commission (NRC), "potentially affecting the water intake structure" that pumps cooling water through the plant."
The plant had previously been shut down for scheduled refueling and maintanance and so the cooling pumps were not essential yesterday at the time of the flood. However, the NRC warns that a further rise "could submerge the service water pump motor that is used to cool the water in the spent fuel pool, potentially forcing it to use emergency water supplies from the in-house fire suppression system to keep the rods from overheating," a situation reminiscent of that which followed the Fukushima disaster last year.
According to the NRC, the 43-year-old nuclear facility remains at alert status after being upgraded from an "unusual event" at about 9pm Monday night. The second-lowest in a four-tiered warning system, the "alert" indicates that conditions are not catastrophic but signals a "potential substantial degradation in the level of safety."
In addition to the concerns in regards to the spent fuel pool, small outages also plague the facility. In a statement made on Tuesday, Governor Christie said the facility "lost a portion of its warning-alarm system Monday night, but other warning signals continued to function." The plant's owner, Exelon Corp. added that "power was also disrupted in the station's switchyard, but backup diesel generators were providing stable power, with more than two weeks of fuel on hand."
The Associated Press writes:
Although nuclear plants are built for resilience, their operations get more complicated when only emergency personnel are on duty or if external electricity gets knocked out, as often happens during hurricanes.
“When external power is not available, you have to use standby generators,” said Sudarshan Loyalka, who teaches nuclear engineering at University of Missouri. “You just don't want to rely on backup power.”
Oyster Creek is not the only nuclear facility at risk because of the storm. One of the units at Indian Point, a plant about 45 miles north of New York City, was shut down Monday because of external electrical grid issues. In a press release (pdf) issued Tuesday, the NRC writes that Salem in Hancocks Bridge, NJ was manually shut down early Tuesday due to a "loss of condenser circulators due to the storm surge and debris." Also, Constellation Energy Nuclear Group's Nine Mile Point 1 reactor in upstate New York underwent an automatic shutdown after an electrical fault in an event that was "likely storm related."
The storm also caused power reductions at both units at the Limerick nuclear plant in Pennsylvania and one unit at the Millstone plant in Connecticut.
According to the NRC, conditions are still safe at "Oyster Creek, Indian Point and all other U.S. nuclear plants."