No damage or injuries at area nuclear power plant

By Steve Mocarsky smocarsky@timesleader.comStaff Writer

SALEM TWP. – If the nuclear power plant near Berwick was just 30 miles closer to the epicenter of Tuesday’s earthquake, the 5.8-magnitude tremor would have exceeded the plant’s safety design specifications.

Diane Screnci, a regional spokeswoman for the Nuclear Regulatory Commission, said all nuclear power plants are designed to withstand the most severe earthquake ever recorded within a 200-mile radius of each plant.

The Susquehanna Steam Electric Station, about seven miles from Berwick, is about 230 miles from Louisa County, Va., the site of the earthquake’s epicenter, according to the U.S. Geological Survey.

Joe Scopelliti, spokesman for the PPL Susquehanna Steam Electric Station, said seismic activity at the plant was well below levels it was designed to withstand. The plant’s two seismographs detected ground movement comparable to a magnitude 3.5 quake. The plant is designed to withstand a quake of at least a 5.6 magnitude, he said.

Plant officials declared an emergency after the earthquake tremors reached Salem Township, but an operating reactor was not shut down. The 700-ton turbines in the reactors are designed to automatically shut down if vibrations exceed a certain level, he said.

“At 2:05 p.m., we did declare the lowest-level emergency – an unusual event,” Scopelliti said. “We walked down the plant from top to bottom to detect any damage and none was found. There were no injuries to employees reported.”

Reactor Unit 1 continued to operate at full power, Scopelliti said, but the quake led staff to postpone the start-up of Unit 2, which shut down Friday “as it was designed to do” after “a single-point failure in wiring” was detected.

Plant staff had been testing a new digital control system that was recently installed when Unit 2 automatically shut down because the failure was detected. Unit 2 was in the process of being restarted Tuesday, but because of the earthquake, start-up was postponed as staff continued inspecting the plant, he said.

“We are taking prudent steps to check the condition of our plant,” Scopelliti said. “The safety of our plant neighbors and employees is our primary concern.”

PPL ended the emergency alert at 9:10 p.m. after a walk-down of the plant resulted in finding no damage, Scopelliti said Tuesday night, adding that start-up of Unit 2 had resumed.

Two nuclear reactors at the North Anna Power Station in Louisa County, Va., were automatically taken off line by safety systems around the time of the quake.

After shutdown, the Dominion-operated power plant was being run off three emergency diesel generators, which supplied power for critical safety equipment. A fourth diesel generator failed, but it wasn’t considered an emergency because the other generators are working, according to the NRC.

Dominion said the reactors were shut down safely and no major damage was reported. The quake also caused Dominion’s newest power station, Bear Garden in Buckingham County, Va., to shut down automatically.

Screnci said North Anna declared the second-lowest of four emergency alert situations.

Dominion spokesman Jim Norvelle said the plant was designed to withstand an earthquake of up to 6.2 in magnitude.

Plants in addition to Susquehanna declaring unusual events, which indicate a potential decrease in plant safety, include Peach Bottom, Three Mile Island and Limerick in Pennsylvania; Salem, Hope Creek and Oyster Creek in New Jersey; Calvert Cliffs in Maryland; Surry in Virginia; Shearon Harris in North Carolina; and D.C. Cook and Palisades in Michigan. They all continue to operate while personnel examine their sites.

In addition to having its resident inspectors conduct inspections at those plants, Screnci said the NRC was monitoring them from its Incident Response Center in King of Prussia and commission headquarters in Rockville, Md.

The Associated Press and Reuters news agency contributed to this story.