As the sun rose this morning over Virginia Electric and Power Co.'s massive North Anna nuclear power plant, a series of alarms sounded. Frantically, technicians began a complicated procedure to shut the plant down. f

Within minutes, Vepco officials -- operators of the 934 megawatt North Anna Unit 1 reactor -- had placed calls to the governor's office in Richmond, to 13 state agencies and to local officials in five counties, alerting them to the possibility of a nuclear accident from a power plant gone out of control.

But here on the streets of Mineral (population 403), five miles south of the plant life went on as usual. Pete Michael Ansel, 59, assumed his customary pose on the steps of an unused train station and announced: "Hell it's just a test . . . nothing to get excited about."

It was a test, VOPEX-80 (Virginia Operation Planned Exercise), the largest simulated radiological accident at a nuclear power plant in the United States and the first since the Three Mile Island accident in March 1979. More than 300 federal, state and local personnel participated in the eight-hour exercise designed to test Virginia's response to a reactor emergency.

"The exercise was designed to confront the state and the communities within a 10-mile radius of the plant with situations that might occur as the result of an emergency," said Mike La Civita of the state's Office of Emergency and Energy Services.

For Vepco officials and their customers, the test was of special significance. Two weeks ago the Nuclear Regulatory Commission denied the utility an operation license for its long-completed North Anna Unit 2, pending the successful outcome of today's exercise.

Last June, North Anna 2 became the first new nuclear reactor to achieve a self-sustaining nuclear chain reaction since the Three Mile Island accident. But an NRC moratorium on new reactors that followed that accident has kept the Vepco unit idle.

Today's test brought a number of top state officials to North Anna, including Virginia Gov. John N. Dalton, a champion of nuclear power, who has repeatedly attacked federal authorities for delaying the startup of the second plant here. Vepco President William W. Berry, who greeted Dalton, said his participation was "another sign" of the state's commitment to push for nuclear power.

The test came complete with a news center, on the second floor of the Mineral Fire Station, where utility officials briefed newsmen on how serious the mock disaster was. At one point spokesman Tom Jarvis told reporters that a cloud of steam that escaped from the plant had sprinkled radioactivity over people within a 10-mile radius of the site.

And the news was filled with jargon of the industry. "At a distance of 1.75 miles from the plant, the dosage was 1,020 millirems per hour," said Vepco's Ashby Baum. "This means that people within that range are receiving the maxium average dosage allowed a (Vepco) station worker in 36 days."

At 10:50 a.m., teams of state and local police evacuated 60 people from homes in a two-mile radius of the plant and took them to two high schools out of the immediate area for decontamination procedures, La Civita said. In a real emergency about 6,000 people would have to be moved from the area, he said.

"I thought they handled it very well," said 80-year-old Mrs. Lewis Foster, one of the 60 residents who volunteered for the evacuation test. Each resident was checked with a Geiger counter at the schools and loaned new clothes as part of the exercise.

"I didn't know what they were doing, but I let them do it," Foster said. "I even shook hands with the governor," who visited the evacuated residents at both schools.

The test also simulated a fire inside the reactor building during which a member of the Vepco fire crew broke a leg. He and a busload of residents suffering simulated radiation contamination were flown by a National Guard helicopter to the Medical College of Virginia Hospital in Richmond. g

At 2 p.m. Baum announced, "The state of emergency has ended." But both Vepco and state officials were reluctant to declare the test a success until they hear from federal officials who monitored the exercise, probably next week.

The utility officials were optimistic, nonetheless, that they had passed the inspectors, scrutiny and they said they hope that the North Anna Unit 2 would be allowed to begin commercial operation next week.

Today's test, which involved a five-county area, was being graded by 21 members of the Federal Emergency Management Agency as well as officials from the Nuclear Regulatory Commission, according to Vepco spokesmen.

"The FEMA team will have their report finished and submitted to the NRC by early Tuesday," said John MdConnell, an FEMA executive.He said the agency hopes to hold similar tests at all other nuclear plants in the nation.