WASHINGTON -- The nation's nuclear power plants hummed into the new millennium Saturday without interruption of electricity or safety compromises, but some nagging glitches, though not safety-related, caught public attention.
"None of the plants experienced problems that compromised safety systems or disrupted the performance of the plants," said Bob Jasinski, a spokesman for the Nuclear Regulatory Commission.
No sector of the energy industry attracted greater scrutiny among federal planners for the Y2K rollover as the country's 103 commercial reactors. Ninety-nine of the reactors were operating as the new year began.
Energy Secretary Bill Richardson made clear he was worried about the performance of reactors in former Soviet states, especially those in Ukraine, the site of the Chernobyl catastrophe in 1986.
But the transition came without incident in Russia and Ukraine, and almost error-free in the United States.
Nevertheless, officials said Saturday that Y2K-related glitches were reported by at least seven of the American reactors overnight, all involving computer systems used for support functions and not plant operations of safety devices.
"They were very minor glitches," said Carl Pateriello, the NRC's deputy director for operations. "Most of them were corrected by rebooting the system." He said they reflected the low threshold the NRC is using in requiring Y2K incidents to be reported.
According to the NRC:
--At the Palo Verde nuclear reactor in California, a clock controlling noncritical data displays did not synchronize properly with global positioning satellites at midnight. It was quickly reset.
--At the Arkansas nuclear plant near Russellville, Ark., a post-midnight check found a problem with computers that automatically track movement in and out of radiation-controlled areas of the plant. A spokesman said the system quickly was shifted to manual and corrected by a software change.
--At four reactors at three plants -- Indian Point and Nine Mile Point, both in New York, and Millstone in Connecticut -- computers tracking weather data failed briefly. There was no impact on operation of the plants.
--A display failed to portray monthly trend data at the Pilgrim plant in Massachusetts. The problem was corrected within 2 minutes.
Federal regulators and industry representatives said the fact that such incidents would get as much attention reflects the smooth Y2K transition of the industry.
"The Y2K computer bug has been rendered harmless," Ralph Beedle, a senior vice president at the Nuclear Energy Institute, the industry trade group, proclaimed in a statement Saturday.
During the 30 hours preceding the new year, two reactors unexpectedly shut down for non-Y2K reasons. The Catawba reactor in South Carolina had a turbine problem, and the Limerick reactor in Pennsylvania had a transformer malfunction, officials said. The two D.C. Cook reactors in Michigan previously had been shut down.
Although federal officials in Washington described the Catawba problem as turbine-related, a spokeswoman for plant operator Duke Power said late Saturday that the cause still had not been determined conclusively. Plant officials were "investigating to determine if it is indeed a turbine-related problem," Guynn Savage said.
Another reactor, the Vogtle Unit 2 near Augusta, Ga., resumed operation on Friday after having problems restarting. It had been shut down Dec. 27 to make some repairs.