It will be the fifth go-around since 1967 for residents of Arlington's Colonial Terrace neighborhood who have discovered to their dismay that developers covet their tree-framed neighborhood on the fringes of Rosslyn as much as they do.

One after another, major developers have come into the county with blueprints for skyscrapers that would radically transform the tiny Colonial Terrace enclave of single-family homes and low-rise garden apartments and condominiums by extending Rosslyn's high-rises another two blocks west.

And one after another, the County Board has rebuffed the developers, reasserting its firm resolve to draw the line on high-rise encroachment into residential areas along the Rosslyn-Ballston Metrorail corridor. Despite the attraction of the proposed project that will add to the county's housing stock in Rosslyn, the board is not expected to approve the plan.

"I don't see any rush on the part of the board to change our past policy," said board member Ellen M. Bozman of the latest proposal from an Alexandria developer to erect a 12-story, 256-unit rental building.

"This place has had a long public record, which should be quite clear to anyone reading it, that the county expects to keep a low profile on Colonial Terrace," she added.

The 5.5 acre site is located at the northeastern intersection of Colonial Terrace and N. Ode Street, in a neighborhood sandwiched between Rosslyn and the low-rise Colonial Village residential complex.

If approved, the project would displace the students, young professionals and retirees who now live in the three single-family homes, a 32-unit garden apartment complex and a four-unit building that occupy the site.

But Martin D. Walsh, an attorney with the law firm representing the developer, wrote the board that it would also add to the county's low stock of rental units.

Crow, Terwilliger and Michaux Inc., the developer, had asked for County Board action this Saturday, but is now seeking a deferral until Aug. 17 in order to revise its plans and meet again with Colonial Terrace residents who have been flooding the board with letters opposing the project. Representatives of the firm did not return several telephone calls.

"There's enough land in Arlington where people can build high-rises without forcing the little neighborhoods out," said Charles Gander, who has seen many changes in the 27 years he has lived at 1593 Colonial Ter. "Anything like that project will be the downfall of the Terrace."

"That building would be just too big a monstrosity for this little area," Gander added, and would result in "one big, huge, wide, thick high-rise corridor all the way up to" Ballston.

Under existing county zoning and land use designations for the area, the developer has a right to build up to six stories at Colonial Terrace. Any greater height requires approval from the county, which has invested about $635,000 in community improvements in the area since 1979.

Nan Terpak, an attorney with Walsh's law firm, said it would be "economically unfeasible to do anything shorter" than the current proposal, which calls for the "terracing" of the building from seven to 12 stories.

Because the project would be a rental building, the developer hopes to get about $25 million in tax-exempt financing, which would reduce overall costs and allow for lower "This is a distinctive little neighborhood which somehow, miraculously, still exists in Rosslyn . . . . If this project is approved, it would disturb the tranquility of the neighborhood . . . . It would absolutely signal the demise of our community. There would be no sense of neighborhood left." -- Resident Melinda Zimmerman rents for low- and moderate-income tenants, according to Edward B. Brandt, the county's housing director. Monthly rental prices, projected for 1988 when the project is targeted for occupancy, are estimated to run from almost $600 to $1,500, he said.

Preliminary plans call for the developer to borrow the money through a cooperative agreement Arlington has with the Alexandria Redevelopment and Housing Authority to provide financing for privately sponsored projects in the county.

Some tenants would be charged the higher rents for the units with scenic views of Washington "to balance the project out, to make it work economically," Terpak said.

Because of objections from Colonial Terrace residents, the county's planning staff and a county commission that reviews plans for development sites, the proposed project has been scaled back, Terpak said.

The units have been cut from the original 262 to 256 and the number of parking spaces has been increased from 271 to 306, including 13 surface spots. An adjacent parcel at 1504 Colonial Ter. would be set aside for a park.

But the revisions have done little to appease residents there, who are fearful that the county will extend the boundary for high-rises into their block as a previous board did when it approved the 14-story Atrium condominium on Key Boulevard.

In that case, the high-rise boundary was moved from Wilson Boulevard to the south side of Key Boulevard because the Atrium's developer agreed to buy and give the Arlington Housing Corporation a low-rise residential complex across the street for low-income residents.

"This neighborhood is going to look like Crystal City or [downtown] Rosslyn in a matter of months or years if they keep tearing down green space," said Terrace resident Melissa Hollis, citing the intrusion of the Atrium on the neighborhood.

Melinda Zimmerman, one of the organizers of neighborhood opposition, said, "I choke on the idea of another high-rise. This area has old, old shade trees, lush trees as far as the eyes can see."

"This is a distinctive little neighborhood which somehow, miraculously, still exists in Rosslyn," said Zimmerman, who has helped collect 220 signatures on a petition against the proposal. "If this [project] is approved, it would disturb the tranquility of the neighborhood . . . . It would absolutely signal the demise of our community. There would be no sense of neighborhood left."

Neighbors say they are also concerned about the extra traffic the proposed project would bring. The county's staff has estimated that peak-hour vehicle trips there would increase from an average of 30 to 131.

Previous proposals for development in the Colonial Terrace neighborhood have been rejected, including a 1972 plan from the Atlanta-based Portman and Associates for a $70 million complex there that would have included a 17-story hotel.

Just as that rejected proposal focused countywide attention on development policies then, resident Gander said he expects this most recent one will also: "The whole of Arlington will be looking at what the board does because of what it will mean for [containing high-rise growth] in the rest of the county."