Fairfax County officials are considering possible changes that would alter dramatically the way the county establishes development patterns.

The county planning staff has produced three alternatives for changing the method officials now use to update the Fairfax comprehensive land-use plan.

Members of the county planning commission have scheduled a special meeting on Sept. 10 to go over the proposals. County planners and elected officials said they would like to see some changes in the process implemented before mid-December. That is when, under existing procedures, amendments to be considered during 1986 would have to be filed.

The Fairfax Planning Commission's chairman, George Lilly, said the review "may give us some way to clean up the process."

He called for a better definition "of the fine line between a plan amendment and a rezoning."

The process for amending the land-use plan, the governing document for land-use decisions and rezonings, has come under harsh criticism from county officials, residents and developers this year. Fairfax officials were confronted with more than 350 proposed changes to the land-use plan this year.

Far too many of those requested changes amounted to virtual rezoning applications, county planners said. Planners said that people seeking amendments to the master plan often dealt with details of a particular project, rather than whether the land in question already was planned, or set aside, for the best long-range use. Under county regulations, specifics of a project must be dealt with in a rezoning application rather than in a change to the county's master plan.

In addition, action on more than 75 of the 350 changes was deferred pending the outcome of several special studies that still are under way. For example, the county has not acted on 26 proposed changes in the Route 50/I-66 area known as Fairfax Center because planners are reviewing the existing land development plan for that section of the county. The county also deferred all proposed changes in areas near Metrorail stations pending approval by the board of supervisors of development plans for the land adjacent to each station.

While planners are examining ways to change the amendment process itself, they are also working on proposed amendments left over from earlier this year.

The process, which has been the subject of much public debate in recent weeks, is known as the annual plan review (APR). The system basically operates on a triennial cycle. This was the third year in the cycle and every proposed change to the plan filed was given an automatic public hearing by the planning commission. Only items approved by the commission were sent to the board of supervisors for action.

Under the existing system, applications for changes in 1986 and 1987 will considered only if they meet strict criteria established by the county. This is a factor that has angered developers, landowners and homeowners in the past two years as they have watched the county building boom continue.

"Two of the three proposals" for changing the process "would change the APR as we know it. They would totally alter the plan review process," a top county planner said.

One option would revise the process and criteria for submission of proposed amendments. The alternative plans would use existing studies of particular areas as the basis for land-use decisions, officials said.

The planning commission recently received an overview detailing the three options. Lilly said the timetable the staff wanted then was a bit too fast for many planning commission members to work with.

Planning staff members are expected to present pros and cons of the three alternatives at the Sept. 10 meeting. What county planners are calling a "blue-ribbon commission" would then study the alternative proposals, which would have to be approved by the planning commission and the board of supervisors before going into effect. Members of that commission will be appointed this fall.

Now is a good time "to look over the process again," Lilly said. "That is not to say a major change in the process is necessary. Undoubtedly, there are improvements that could be made."

County officials said developers have complained they did not have adequate time to make their cases before decision makers. Homeowners seeking changes have also complained about the process.

Lilly said one major problem in the present system is that anybody can propose a land-use change for any site -- even people who don't own the property -- without notifying the owners.

County leaders said homeowners complain that the notice of proposed amendments often is insufficient to allow them time to organize opposition.

This year, Fairfax posted bright yellow signs on every piece of land for which an amendment was proposed. In addition, every household in the county received a newspaper-like pamphlet listing all proposed changes. But many residents say those two procedures are not enough, and officials readily admit that posting visible signs on large construction sites is difficult, especially when property may include several hundred acres.