A developer has tentatively proposed constructing a nine-story apartment building on a wooded portion of the Tregaron estate in Northwest Washington, prompting opposition from neighbors in surrounding Cleveland Park and Woodley Park who helped defeat an earlier development plan.

The developer, Roy Demmon of San Francisco, presented his plans to community leaders at a meeting late last month. But Demmon stressed that his plans are flexible and that he has not yet talked with the tract's owner, said several residents who attended the meeting.

"The reaction was very negative," said Peggy Robin, chairman of the Advisory Neighborhood Commission in Cleveland Park who lives near the estate. "It's fairly much out of keeping with the neighborhood . . . . It would just tower over the Tregaron mansion, and it would lose its scale."

The estate, at 3100 Macomb St. near Connecticut Avenue and Rock Creek Park, was once owned by Joseph E. Davies, United States ambassador to the Soviet Union before World War II. In 1980 his heirs sold it for $4.6 million in a court-ordered settlement.

The Washington International School acquired the estate's Georgian-style mansion and about six acres, and a group named Tregaron Limited Partnership bought the remaining 14.6 acres. The partnership's major owner is Shaul Eisenberg, an extremely wealthy Israeli financier, said one of his Washington attorneys.

Lawyers for the property's owners confirmed that they had not been approached to sell the property, but added that it is inevitable that the prime real estate will be developed. "At some point the property will have to be" developed, said Whayne S. Quin, a real estate lawyer representing Eisenberg's interests. "A person is not going to continue to pay taxes" on the property "and lose money year after year."

Demmon could not be reached for comment. Local developer Eugene Ford, who jointed Demmon at the meeting and expressed interest in joining the development team, also could not be reached.

Angela Vallot, a lawyer representing Demmon, said the proposal for an apartment building for the elderly was "a very preliminary plan . . . . It could be an apartment complex, cooperatives, or rental."

Residents at the meeting added that the developers said their preliminary plan calls for an apartment building -- with some health care services -- designed for the wealthy elderly who have moved out of homes or apartments but are not ready for nursing homes.

The proposal called for at least 200 residential units, said residents at the meeting.

Vallot said the meeting was designed "to get some ideas from" residents and to gauge their response to various plans.

"We don't want the citizens to get up in arms and form coalitions" against the proposal, she said. "We aren't there yet . . . . We realize the importance of feedback from the community."

Lisa Koteen, a Woodley Park activist and local advisory neighborhood commissioner, said "the group was cordial because we didn't want to discourage a developer from meeting with us. But people told them straightforwardly, 'This is too much. It's more than we can accommodate.' "

Three years ago neighborhood coalitions helped persuade the D.C. Zoning Commission to reject a proposal by Tregaron Limited Partnership to build 120 expensive town houses, with proposed prices of up to $330,000 apiece, on the historic site. The commission sided with the opponents who said the development was too large, would cause traffic problems and would injure the character of the land.

But one commission member, National Park Service representative John G. Parsons, said then that instead of building detached houses, the project could be limited to clusters, and maybe built in mid-rise structures, to preserve the natural setting.

The current R-1-A zoning would allow a developer to build about 80 detached single-family homes on the hilly property, which abuts Klingle Road. But several persons knowledgeable about the property said that because of the hilly terrain and the limits placed on development because of the property's historic nature, it is doubtful that detached homes would be built there.

Vallot said the proposal for a high-rise apartment building was in part an effort to respond to the city's and the community's position that the natural setting should be maintained. A high-rise "would go up instead of out," she said.

She added that Demmon's representatives have met informally with officials of the D.C. Office of Planning, who were said to prefer a high-rise to single-family homes scattered across the site. City officials could not be reached.

Demmon is "very sensitive about the environment and landscape design," Vallot said.

The Zoning Commission, in addition to several other advisory agencies, would have to approve any proposal for the site.

"One lesson that came out last time was it's not worthwhile taking this forward in the face of opposition from the community and the other agencies," Robin said. The developers "would just be wasting their time. The developers know this, and that's why they asked to meet with us first." CAPTION: Picture, The Tregaron estate in a file photo taken in 1980, the year the heirs of Joseph E. Davies sold the property for $4.6 million. By John McDonnell -- The Washington Post; Map, Tregaron Estate