In response to pressure from community residents and planning officials, a national development firm has modified its $38 million residential project in Arlington's Ballston area.

Trammell Crow Co., which submitted a request during the summer to build a 10-story apartment building on land near Washington Boulevard and Glebe Road, is now proposing a scaled-down apartment building and two smaller ones.

Neighbors of the project, who met recently with the developer to discuss the new proposal, said they are happy with the modifications, which they describe as closer to what was approved for the site five years ago.

"I'm pleased with how responsive they've been," said Sandy Keyes, president of the Ballston-Virginia Square Citizens Association. "Now they're in the ball park."

In 1982, the Arlington County Board approved a site plan request of the Oliver Carr Co. to build three office buildings, a medium-height apartment building and eight three-story apartment buildings on a nine-acre parcel bounded by I-66, Washington Boulevard, Glebe Road and property just north of Fairfax Drive. The board approved an additional five stories for one office building in exchange for a commitment from the Carr company for a variety of residential buildings on the site.

While work is under way on the office portion of the project, the Carr company contracted out the residential section of the site to Trammell Crow this year.

In late August, Trammell Crow applied for a site plan amendment that would have allowed the firm to build one 344-unit 10-story apartment building instead of the 260-unit apartment building ranging in height from four to 10 stories and eight 3-story residential buildings with a total of 84 units that were approved originally.

"They weren't asking for an increase in density, they were asking for a different type of structure," said Arlington planner Bob Klute. "As we interpret it . . . the issue was the idea that a deal had been made."

When Trammell Crow met with civic groups this fall, residents opposed the changes. And when the firm's amendment request went before the county's site plan review committee in late September, committee members directed the developer to restore the variety of structures contained in the original plan.

Jonathan B. Cox, a development associate with Trammell Crow, said the firm's revised proposal will include a 293-unit apartment building six to 10 stories high and 2 three-story residential buildings with a total of 51 units. The tapered apartment building will stand along the western edge of the site near I-66, and the two smaller buildings will be near the eastern border of the property next to Glebe Road.

Cox said the plans call for significant landscaping on the property with a small park on the northeast edge. The project will have 400 spaces of underground parking with some surface parking for visitors.