Over a half-eaten Greek salad and her third cigarette since lunch began, Andrea Weirich summed up her job of selecting garbage landfill sites in Montgomery County: "It's a painful process," she said bluntly. "It's painful for the citizens and it's painful for the government."

Weirich, who earned a bachelor's degree from Wellesley College and a master's degree from American University, holds one of the toughest, most publicized jobs in county government.

In Montgomery County, where residents balk at the advance of shopping centers, highrise apartments and sometimes fire stations, and protest against landfill has been heavy.

As a result of Weirich's recommendations, community residents have yelled at her, argued with her, picketed her and sometimes sympathized with her.

Her advice has caused grief and anxiety among hundreds of residents throughout the upper and midportions of the county whose communities, at different times last summer and fall, have been fingered as possible sites for landfill.

"You can't take it personally," she says often about the citizen protests directed at her. "We ARE the negative project.This is not like building a fancy office building that's going to win architectural prizes."

As chief solid waste planner for the county, Weirich oversees the day-to-day work done by geo-technical consultants studying possible sites. She and the consultants produced reports on preliminary sites for landfills - or, as the residents distastefully call them, garbage dumps.

From those reports, County Executive James P. Gleason chose last December the sites that would be studied further - two in Laytonsville and two in Potomac. Based on further studies and Weirich's recommendations, Gleason sometime in the fall will choose the final site or sites for landfill.

The landfill project is Andrea Weirich's baby as far as the county Office of Environmental Planning is concerned, and she embraces it enthusiastically. Weirich, who spent college days in student government, early working days in Frampton, Va., government, and free time as a civic activist in Rockville city government, said landfill is Montgomery County government at its most crucial and challenging.

"I like to take a subject and try to make the system work," said Weirich. "And the system hasn't been working." Landfill involves a lot of people, she explained. "It's the kind of thing everyone wants their finger in," Weirich said. "You say it's landfill, but it involves local citizens, planning officials and politicians."

Weirich deals with them all. "My job," she began, in the outline form her conversation takes, "is to a) get information out to the citizens, and b) get information back from them."

After countless meetings, more than 1,500 pieces of personally written mail, and a half year's worth of phone calls that came in at the rate of 50 to 75 a day, Weirich still likes her job.

"It challenges you on every front, but it's very wearying," she said ruefully. "You can't do it forever."

At 38, she is thin, blond, carefully made up and always well-dressed. She is pretty, but with a severity to her face. She is intense about her work, overprepared for business meetings.

In her funnier moments she has been known to tell new acquaintances that she is a garbage planner. She keeps a bright aluminium garbage pail with bright pink bow - a birthday gift from friends - in her office and tacks up on the wall the more creatively insulting letters from landfill protesters.

But the meetings with community residents are serious business. "I usually need a good drink when I come home after one of those meetings," said Weirich. "They're pretty rough."

Weirich discusses those meetings with the same cool, unflinching tone of voice that she uses at the meetings. She sounds official but sympathetic. Her soft gravelly voice is not commanding, but it is earnest. She stumbles sometimes, but she always knows what she has to say and she says it.

There is nothing harsh about her manner in meetings or in conversations. If she is unnerved, she hides it behind her straightforward manner.

"You sort of tighten up," she explained about the meetings. "You know everything you hear is going to be criticism. You know you're going to be hearing viewpoints from a certain advocacy position. You have to steel yourself for walking into a meeting when you know you're going to be beat about the head.

"You're being watched every second," she said. "Every misstatement you make, you're pounced on. When you write something it's taken out of context.

"What you feel from the citizens is total hostility, total emotion," she continued. "You say to yourself, 'Why can't I get this across?' I don't feel angry. I feel frustrated."

Her husband, Bob, an engineer, worries about her, she said. "After one bad meeting, I felt like I'd been out in a dark alley and beaten," she recalled. "When I got home I just said, 'Bob, that's the worst meeting I've been to.'"

Landfill plagues her life. "Your family gets uptight because you can't get your mind off the job," she explained. "That's why when I have time, I don't sit around the house. I'd just think about the project."

She and her husband play touch football and tennis in warm weather. This winter, they took their two children - Erica, 9, and Kurt, 11 - on a one-week skiing trip to Stowe, Vt.

Weirich brushes off any feelings of bitterness toward the citizens fighting landfill. "I understand the fears," she said. "I would have them too. I would worry about litter, about odors, about property values. Ninety-nine percent of them are honest, straightforward, sound people. We can agree on nothing, but I still like them personally."

Those she doesn't like are those peddling hysteria for effect - certain residents, certain politicians "who should know better. I had one politician stand up at a meeting and say "The staff don't know what they're doing. Don't believe them. Come to me.' I resent it. There're just a couple who are very demagogic. The vast majority are responsible.

"Emotions are a very important part of this," she continued. "But if someone says, 'I just don't want the dump, I don't want to discuss it,' fine. But meanwhile we have to get on with our work. We have to get through our analyses. What's useful is saying I don't want the dump because . . ."

Weirich gets that information sometime. "Another meeting was super," she said glowing. "It was so neat. We were giving our information to the citizens and the citizens were giving theirs to us."

Weirich says she wants to keep her word to all those citizens that she entreated to cooperate with her. "When the consultants are making plans, I tell them, 'I want you to specify what size trees and what size tree trunks,'" she said, her face set grimly. "Because I want to move this through the system. I want to see things get done that I say will get done."