She is sitting in the long brown grass, her left hand gently passing over the two phone numbers written in blue ballpoint on the right knee of her dirty khaki Levi's: 544-2386 and 544-0397, the numbers of the lawyer, the numbers to call from jail.

"I'm supposed to read the names of our group off as fast as I can and then hand the phone to someone else. I figure they can take everything away from us, but I hope they don't take my pants." Her name is Diane Ross. She is a former art gallery owner, a teacher of ceramics. Her well-cut blond hair is now straggling; the face tanned on tennis courts now weathered from four days in the San Luis Obispo sun. "Do they have showers in jail?"

Just now, just an hour before the final decision to start the blockade, Ross' "affinity group," known as the Reactors, is meeting to discuss final strategy. Above them are the power lines and towers leading to the Diablo Canyon Nuclear Power Plant, invisible behind the soft, rolling hills of the California coastal range. Just down the road, newly installed on a telephone pole, is a warning siren to screech the alarm if something should go wrong at the plant and send the residents of this farming community running.

"We're going to get in a line, lock arms and sit . . . is that what we're doing?" asks Vida, the children's bookseller. She started an underground newspaper when she was in the seventh grade, called We the People.

"I think locking arms produces struggle. I like holding hands. It feels good. It feels safe and caring, but it doesn't feel locked," replies Janice, the owner of a computer business.

"And we couldn't scratch or pick our nose," adds Jim, the newspaper truck driver.

The meeting goes on for 20 minutes until all 11 blockaders agree. They will go in holding hands. Two-by-two. They will sit down in a circle before the main gate into Diablo. They will not go limp. They will give their names.

As one of the members stands up, Bonnie, the house painter, asks him if he is going into town. "Find out what's going on at my house. If the kids are all right."

In 1977, 11 years after Pacific Gas and Electric broke ground on the coast halfway between Los Angeles and San Francisco for a new nuclear power plant to heat the homes and brown the toast of the populace, a small group met at a county camp just outside the town named for St. Louis, bishopking of France. Sam Lovejoy from the Clamshell Alliance was there, and Raye Fleming from Mothers for Peace and Liz Walker from the American Friends Service Committee. And there were others, gleaned from the ranks of disarmament, anti-Vietnam war activism and civil rights who met in the brown cabins and decided to take on Diablo. They named themselves the Abalone Alliance, after a small, delicious mollusk, thousands of which were killed by copper poisoning when Diablo tested its cooling system in 1975.

(Raye Fleming had been fighting the plant since 1973, when an earthquake fault was discovered running right along the coast, just 2 1/2 miles from the plant. California is riddled with earthquake faults; PG&E has had to shut down two of its plants and abandon the site of another because of the danger of the shifting ground.)

The Abalone Alliance began to organize its first Diablo sit-in to take place in August. It is a mistake to think of the Abalone as a stratified organization. It is rather a huge, multicelled creature, its basic unit being an "affinity group," 15 to 20 persons who join with others during "an action" to make a "cluster" or a "wave." During the Spanish Civil War, there were grupos de affinidad; at Whyl, West Germany, where 28,000 blocked construction of a power plant in 1976, there were affinity gruppe; there is the Hard Rain in Boston and Yellow Life Rose in Texas and the Rocky Flats Truth Force in Colorado.

An affinity group is at once a large, playful family -- in San Luis Obispo, it includes a section named No Nukes and Hold the Anchovies -- and a deadly serious, purposeful unit of nonviolent combat.

"You don't know if there's going to be tear gas, dogs, whether tall people are intimidating, whether you look too vulnerable on the ground," says Vida, twisting a piece of grass between her fingers. ". . . You have to try to go over and over it until your responses become automatic, because once you're in the blockade, it's like a roller coaster, you don't realize what's happened until it's over."

At the heart of the nonviolent training is the role play, first taught to the Abalone by Quakers is the role play. Over and over, the Reactors have imagined themselves to be police ("maintain eye contact"); in jail ("I wanna get out of this. I can't stand this."); facing attack dogs ("Don't move. Try to put your hands behind your back."). The exercises have been refined so much that one trainer is writing his master's thesis on them.

Robert Blake, star of the TV series "Baretta," who stands in the middle of the Abalone encampment in a black T-shirt and straw Panama hat, has taken the training along with his affinity group, the Celluloid Heroes. Around him, the encampment sprawls over 30 acres of cow pasture under the California sun, a gathering of tents and lawn chairs, sleeping bags and balloons over which the sweet, spicy smell of cooking curried rice drifts and wanes. If it were a medieval tournament, the emblems of royalty would be the Magic Marker-painted sheets tacked to the red, green and orange tents: "Concerned Cal Poly Faculty and Staff," "Acorn Alliance," "One Love." A man is juggling chartreuse tennis balls. Over by the medical tent, a group is singing: "Ain't gonna let Diablo turn me around, turn me around, turn me around, turn me around. Gonna keep on walking. Gonna build a new world."

A professor of architecture at California Polytechnic State University, Paul Wolff, who plans to hike into the plant, speaks softly: "In Germany, where I was born, apathetic people allowed the government to take over . . . You have to decide the consequences of doing something and know that the consequences of not doing something are worse."

The alert went out last Wednesday, just when Diane Ross had called Janice Weisman. It was on the radio, the official words: The Nuclear Regulatory Commission's appeals board had just approved Diablo Canyon's security plan, the last step toward clearing the way for low power testing at the plant.

"I put the phone next to the radio and I screamed, 'We're going. We're going.' "

After two months of meeting every week, the Reactors went into action. Diane Ross canceled her Greek dancing date, her planned float in a Samadi relaxation tank, went down to Mrs. Gooch's health food store to buy dried apricots and sesame seeds, called up the people to look after the four calico cats. Vida Sculley packed up "Walden," "A Room of One's Own" and "The Charlotte Perkins GillmanGilman Reader" and took the dogs to the kennel. Diane Ross washed her yellow International truck and, because she feared roadblocks, removed all the antinuclear bumper stickers. By Friday, they were driving up from the San Fernando Valley to meet just beyond the "Pepper, Corn and Tomatoes" sign out on Los Osos Road.

It had taken a year to get this far. Ever since September of last year, when it began to look as if the NRC would license Diablo, the Abalone Alliance, now made up of 58 antinuclear groups across the state, had said it would blockade it. In June this year, it printed a 60-page "Diablo Blockade Encampment Handbook," which included everything from descriptions of the possible legal charges against the blockaders ("criminal trespass," "unlawful assembly," "resisting arrest," "conspiracy") to a quote from the I Ching, "One must resolutely make the matter known at the court of the king."

It had been 15 years since PG&E had started to build Diablo and run smack into the antinuclear era. At stake is PG&E's $2.3-billion investment, which they cannot pass on to consumers in the form of rate increases until the plant is on line. At stake is the Abalone Alliance's promise to stop it, by land and by sea, with fewer numbers than it had hoped for. The blockaders will sit down on the road before two entrances, swim off the Greenpeace rubber raft into Diablo Cove or march overland to encircle the plant.

Waiting for them, at last count, were 162 highway patrolmen, 500 National Guardsmen as backup, 20 Justice Department agents and an assortment of deputies from the San Luis Obispo sheriff's department. The sheriff's department has had two staff persons working full time on the blockade for six months. "We've got a book full of plans," said Capt. James Wood. They borrowed a computer from Santa Barbara to process arrests, and at one time considered using the San Luis Obispo Public Library as a holding cell.

In mid-afternoon Monday, the Abalone Alliance decided it was ready. By evening, almost 100 blockaders had begun to hike toward the plant under a fine full moon.

At 1:15 yesterday afternoon the Reactors left the parking lot at Avila Beach, 20 miles south of San Luis Obispo, 1 1/3 miles from the main entrance gate at Diablo. About 20 minutes later, the San Luis Obispo sheriff's deputies who had been standing behind the chain link fence next to the gate, wearing green helmets with plastic face shields, carrying gas masks on their thighs and plastic handcuffs in their belts, got into trucks inside the gate and, inexplicably, drove away, toward the plant and out of sight.

Diane Ross, carrying her blue pack and sleeping bag, walked along Avila Road over the bridge from the town, toward the port of San Luis Bay. A Greenpeace black rubber Zodiac boat chugged along in the harbor beneath her, its passengers waving. It was a clear, brilliant day. The fishing boats graced the water like slim watercolor sketches.

Around her waist, Ross wore a Marine Corps olive drab jacket that had once belonged to her husband, a colonel and professor of geography, now dead 10 years.

They were quiet as they walked, occasionally waving at cars that drove by, many of whose riders waved back at them.

Ahead in the long line, the first affinity groups got to the main gate. They carried three scaling ladders built like fold-up stiles; they put them against the gate and climbed over easily, lifting the packs over. The smell of kelp hung heavy in the air. No one tried to stop them.

When the Reactors got to the gate, they sat down in a circle and sang:

"No Diablo,

No Diablo,

No Diablo over me.

Before I'll be oppressed I'll stand up and protest,

For the love of the human family."

They cheered as other blockaders lifted a young man over the gate. His wheelchair followed him. A fourth and fifth ladder arrived and were put up; perhaps 40 people were inside the gate by this time. They sat down on the road.

The Reactors sat on the ground outside the gate, inside the blue line that marked the "No Trespassing" area. They were entertained by the Greedi Killowatts, in white jump suits, who sang:

"I'm sick of them complaining,

The waste is only dangerous for half a million years."

Diane Ross ate a carrot and waited to go over the fence.

Later, the Reactors decided not to climb the fence but to stay seated against the main gate on the outside. The first arrests began at 5 o'clock in the afternoon inside the main gate.

A tall PG&E man came forward and suddenly there was a loud buzz and blue smoke as he whipped a chain saw through each of the five ladders laid by the blockaders along the fence. The demonstrators caught them as they fell. Sheriff's officers came forward and gently took each blockader by the elbow -- some helped with a pack here, some carried a sleeping bag there. Then there was nothing left inside but water jugs in small groups where the blockaders had been.

They were "field booked" at long tables, then loaded into a yellow school bus. A sheriff's department spokesman said they would be taken to a site within the plant's property.

The Reactors moved until they were seated solid against the gate, and held hands.

Diane Ross was crouched, a change of underclothes in her pocket. She pulled out her compact and checked her face. Janice leaned over and joked, "Who knows when you might meet someone, say inside."

"Who knows," said Diane with a touch of gallows humor, "when Mr. Right is going to come along."

A sheriff's officer from San Luis Obispo ordered them to disperse. When they did not, he said: "It is 6:50 p.m., Sept. 15, 1981. You are all under arrest under California Penal Code, Sections 602 and 409."

They began pulling the gates open and away from the blockaders. "Damn," said Diane, "we were suckered. The gates open both ways."

These police from Pismo Beach and San Luis Obispo were rougher than the sheriff's people. Arms were twisted. Water jugs were thrown against the fence. They pulled them by the elbows back through the gates toward a waiting bus.

As Andy of the Reactors took out his small green Bible and began to read from Corinthians, they took him.

When they took Robert, Vida began to cry.

At 7, Diane was the last one left. As the deputies took her arms, she smiled up at them, a proud, polite smile, and was led away.