Scores of residents of the Vienna area flocked to a Fairfax County Board of Supervisors hearing yesterday to protest a developer's "smart growth" plan to build what amounts to a small city near the Vienna Metro station. They contended that the project would overwhelm nearby roads and crowd classrooms.

Under the proposal, Pulte Home Corp. and Clark Realty Capital would replace a 56-acre suburban enclave of single-family homes with two office buildings of roughly 12 stories, some shops and roughly 2,200 apartments, condominiums and townhouses.

Some environmentalists and planners have praised the plan as smart growth because it would focus the overflowing demand for homes in Fairfax County on a relatively small piece of property.

It also would place the new homes and workers within walking distance of the Vienna Metro stop, the western terminus of Metro's Orange Line, offering the possibility that many would take the train rather than travel the region's jammed roadways.

But neighbors to the site west of Fairlee Drive and north of Route 29 have objected. While the project might offer regional advantages, they say, it would create problems in its immediate vicinity, straining roads and schools. Not everyone at the so-called Fairlee development will always take the train, they noted.

The opponents also fear a "domino effect" in which other similar properties near the Metro station would be redeveloped in a like manner and collectively ruin the remaining leafy neighborhoods in the area.

"We still have no area-wide traffic study -- or for that matter any traffic study that has not been bought and paid for by someone else," Doug Stafford, a neighbor, told the Board of Supervisors. "This might be funny if it weren't so tragic for some of our neighborhoods. . . . Stop this train wreck of a plan now."

"Our roads and schools will be overwhelmed," said Mark Tipton, another neighbor. "The costs to all of us in terms of a lower quality of life will be immeasurable."

Two members of the Vienna Town Council, Laurie Genevro Cole and Michael J. Polychrones, also registered their objections.

The county supervisors heard complaints late into the night. The board was not expected to rule on the proposal until later this year.

The project appears to have considerable political momentum. The county Planning Commission unanimously recommended the plan's approval Thursday night, and several environmental activists are lobbying on its behalf.

By contrast with other parts of the Washington region -- most notably in Arlington County -- Fairfax County has taken only small tentative steps toward clustering development around its Orange Line stops, largely deferring to the wishes of residents who prefer fewer new neighbors.

The rhetoric surrounding the Fairlee proposal suggests that Fairfax County leaders believe that they are at a crossroads in the county's development, with vacant land in short supply and the number of workers growing, and that it is time to permit denser development around the Orange Line stops.

"If it is true that growth will continue on a fixed amount of land, and also true that our traditional dependence on cars and roads for transport is approaching its limits, then the pattern of this continued growth must be changed," said Kenneth A. Lawrence, the planning commissioner for the area. "We must change the paradigm of our growth."

In a striking contrast to the neighbors objecting to the project, some residents of the nearby Poplar Terrace neighborhood approve of the proposal. Most of them have banded together in an effort to sell their property to a developer if the county gives permission for more homes in the area.

"Once they go [at Fairlee], it'll make it easier for us," said Pete Young, one of the leaders of the Poplar Terrace area neighbors. "It's the right thing to do for the county. There are 2.5 million people moving to the area over the next 20 years, and they'll need a place to live."