Carefully guarded contract discussions between teachers and administrators in Fairfax County got under way this week and will continue through mid-December.

Although formal contract negotiations and collective bargaining are banned by Virginia law, representatives of the two groups said salary increases and working conditions are among the major topics to be discussed during the meetings.

The two groups are not bound to reach an agreement during the meetings, but both sides indicated they are optimistic about coming to some sort of consensus before recommendations are presented to the school board in December.

"I'm always optimistic and I think our requests are reasonable," said Bill Costello, president of the Fairfax Education Association (FEA), which represents about 6,400 of the 7,000 county teachers. "We went a long way last year in making the community aware of the justification of what we were asking for and I think this will be reflected in the talks."

Last year, the first time established discussions were held since the court ban in 1977, some members of the community and school officials protested what they considered unreasonable salary demands made by teachers.

"This year, we won't have as many problems convincing people that we are just as interested in the way we do the job as well as how we are compensated for doing it," Costello said. "Everyone said we would need a property tax increase to raise teachers' salaries, but it never happened."

A similar reaction was expressed by Warren Eisenhower, assistant superintendent for personnel and a member of the team representing the school system.

"We've been able to come to a consensus in the past, and I'm optimistic we'll able to reach an agreement again this year," Eisenhower said.

While both spokesmen were unwilling to outline details of the talks, Costello said salaries are a major concern.

"We've lost quite a lot to inflation and before we can keep up, we've got to catch up," Costello said.

Costello said teachers and school administrators have been meeting informally during the summer and have tentatively agreed on a few minor issues that do not involve economic questions. Costello said one issue was making sure teacher aides do not work as substitute teachers.

Costello said he also expects teacher representatives to discuss the amount of influence teachers should have on instructional decisions, class size, special education programs and the availability of information about vacancies within the school system.

The school administrators and FEA have set six dates through October for the meetings. The next meeting will be tomorrow. The meetings are not open to the public.