A 2,073-acre upscale golf course community near Haymarket got the blessing of the Prince William Board of County Supervisors on Tuesday, over the objections of neighbors who fear the development will mar the county's rural western end.

By a vote of 7 to 1, the board approved a series of zoning changes to the design for Dominion Golf and County Club, which will consist of 2,800 high-priced detached homes and town houses, a golf course, swimming pools and tennis courts, and 250,000 square feet of office and retail space, all on the one-time site of Disney's controversial theme park.

The developer, Pennsylvania-based Toll Brothers Inc., said it recently has made substantial accommodations to appease area residents. They worry that ground water irrigation for the golf course will suck their well dry and that the influx of families will swell traffic on nearby Route 15 and overburden schools and taxpayers. The developer has the right to build as many as 2,800 homes on the property.

John Elcano, a Toll Brothers vice president, said the recent proffers will enhance the company's ability to "build an upscale community that we think is necessary to attract the upper-level executives and, in turn, attract their businesses."

But neighbors at Tuesday's meeting urged the board to delay its decision, complaining that the company's measures were inadequate and might even worsen the situation by stealing open space for a larger golf course and moving the locations of several public facilities.

"Simply let the full [zoning] process unfold," entreated Fred Potter, 41, an adjacent land owner. "Time's our friend. Two thousand acres in its entirety essentially transforms the western end."

Only Ruth T. Griggs (R-Occoquan) voted against approving the changes. Supervisor Edgar S. Wilbourn III (R-Gainesville), in whose district the project is planned, praised the project's high-end housing, as well as proffers mandating transportation improvements and an extensive water study to test the effects of the development on the ground water supply. He said these additional measures constitute a step up from what would have been built under the bare minimum zoning requirements.

The developers "addressed a lot of the concerns to maintain the rural atmosphere in the community," Wilbourn said Thursday.

Development has not come easy to this tract of land, perched just north of Interstate 66 and west of Route 15. A subsidiary of Exxon sparked intense opposition in 1991 when it obtained a rezoning of the land--then known as Waverly--and tried to build a housing development of similar size to the current plan. That effort was put on hold because of a slump in the real estate market. In 1994, Disney sought to transform the parcel into a historical theme park, Disney's America, but abandoned the idea after county activists and preservationists rallied against it.

Last year, Toll Brothers purchased the bulk of the original 2,500-acre Exxon property and announced its plans for a luxury housing development amid protest from residents hesitant to accept the trappings of more growth.

But because of the existing zoning, houses on this land are inevitable, and Toll Brothers says a recent amendment setting aside 250 age-restricted homes should sweeten the deal by reducing the number of possible children who will live there. Supporters of the $700 million project also point out that the houses will be high-end, selling for an average of more than $275,000 and topping out at $500,000, according to a lawyer for the developer.

Changes approved Tuesday included adding land for nine holes to what will become a 27-hole golf course, possibly moving the locations of a fire station, library and recreational spaces, and making transportation and buffer improvements.

The public debate Tuesday shed light on long-running questions over water in western Prince William, where all the older communities depend on wells. Several area developments under construction, such as gated retired community Heritage Hunt and gated golf community Bellwood, will have water and sewer lines, as will the Dominion property.

Neighbors of the proposed development voiced concern over the accuracy of the pending hydrology study, even after the public outcry prompted an eleventh-hour agreement Tuesday night expanding the developer's responsibility for residents' well-water supplies.

"If our wells do have a problem, that's going to be our problem to pay to connect to city water when it comes," said Diana Nicholls, 54, of Gainesville.

Elcano said Toll Brothers plans to start basic infrastructural improvements next month and to have some houses finished and for sale in spring 2000. Well irrigation for the golf course will not begin until the hydrology study is completed, he said.