The nation's nuclear power plants racked up 2,300 technical violations, mechanical failures and other glitches during 1979, and Virginia Electric & Power Co.'s North Anna I plant reported more than any other unit.

However, it is not clear just what that means.

Ralph Nader's antinuclear Critical Mass Energy Project, which today Nuclear Regulatory Commission, said the listing was distressing.

"It is a profile of an industry rushing headlong toward another Three Mile Island" nuclear accident, project director Richard Pollock said.

Industry members, however, said that reporting lots of events of this kind indicates more safety consciousness than danger.

"In reality, licensee event reports [LERS] are the least serious category of reportable incidents," said James T. Rhodes, manager of nuclear technical services for Vepco. The 130 LERs filed for North Anna I, he said, "indicate Vepco's commitment to scrutinize carefully every aspect of safe nuclear operation."

He called the Critical Mass report misleading and deceptive. Vepco spokesman August Wallmeyer added that North Anna's tally may be higher than those of other plants because Vepco reports each problem individually and because many LERs are "judgment calls that can be reported or not. Our policy is that we want to share the experience," he said.

At Surry II, however, there were apparently fewer experiences to share. The Vepco plant at Gravel Neck, Va., had the sixth fewest LERs, sending in only 11 during 1979.

Critical Mass said in its study that the reported events ranged from minor things such as a misplaced water sample up to serious hazards like cracks in the rods that control the nuclear chain reaction.

Although most LERs involved equipment difficulties, 25 percent resulted from human error. Valve leaks at the Prairie Island plant in Minnesota went unchecked because maintenance personnel were on vacation, the report summary said. Valves to the core cooling system of the Sequoyah I plant in Tennessee were found to be too heavy to open properly in the event of an accident.

The NRC was strongly criticized in its own internal study of the Three Mile Island accident last year for having no systematic procedure for evaluating and acting on the LER's. A special team to organize that was set up in Arpil, but will not recommend a procedure until February.