Plans to build a housing development on the Evans Farm property in McLean near Tysons Corner received the blessing of the Fairfax County Planning Commission last night, clearing the way for a final vote by the County Board of Supervisors next month.

Opponents of the plan, who have fought to preserve the 24-acre parcel as open space, vowed to continue, even as they conceded that the supervisors are likely to follow the recommendation of the Planning Commission.

"We're very disappointed but not very surprised," said Lynn McNulty, one of the leaders of the Coalition to Save Evans Farm. "We're concerned about the impact on our quality of life."

Planning commissioners said construction of 144 town houses, condominiums and single-family detached houses on the land would be consistent with the long-standing plan for that part of McLean. The 12-member panel voted 10 to 1, with one member absent, in favor of the proposal.

"This has not been one of the easier cases in McLean," said commissioner Judith Downer (Dranesville). "But growth is here. I would love to save the farm, but that isn't an option tonight."

Long a favorite spot for families and children who came to feed the ducks and pet the horses and other animals, the Evans Farm also is known for a picturesque pond, a copy of an old mill and a restaurant resembling an 18th-century farmhouse.

Despite its use as a community recreation spot for decades, the Evans Farm has always been private property. Its owner, Ralph Evans, says he has sold the property to the West Group, a development company that has designed an upscale, 144-home community. It has been estimated that Evans sold the farm for about $20 million.

"I'm delighted," Evans said after the vote. "It's a great plan, and I'm just glad the commissioners went along with it."

West Group, the largest developer of office buildings in the Tysons Corner area, has proposed making the project look like a 19th-century village. The company promises to keep some open space on the property and to try to save the most popular features, like old trees, the pond and the mill.

"We're pleased that the process worked," company spokeswoman Kathryn MacLane said. She said construction would likely begin during the first three months of 2000 if the supervisors give their approval.

Members of the Coalition to Save Evans Farm say the future of the property will be a political issue in the November elections. Democrat Barbara Phillips, an opponent of the development, is challenging incumbent County Supervisor Stuart Mendelsohn (R-Dranesville).

In December, the supervisors rejected a bid by the activists to discuss creating a special tax district in the McLean area. Activists had suggested that the money from a special tax on houses and businesses could pay for buying the property from the developer to save it.

The supervisors also turned down a proposal to amend the county's long-range planning documents to reflect a desire to see the Evans Farm turned into parkland. Supervisors said it wasn't right to change the planning documents against the owner's will and when a redevelopment case is pending.

After demonstrating several times during rush hour in front of the West Group's Tysons Corner headquarters, the activists also tried to negotiate a smaller development on the property. West Group officials rejected the proposed compromises.

The Board of Supervisors is scheduled to vote on the Evans Farm development proposal on July 26.