A proposal to build housing for the elderly on a 12.4-acre site partially occupied by a satellite Fairfax County government office trailer has stirred strong opposition in the McLean-Tysons Corner area.

Landowner Kenny Thompson had asked Fairfax County to change the land-use plan for the site to allow for construction of five-to-eight dwelling units per acre. The land use currently would allow two-to-three units per acre but Thompson wants to build housing for the elderly. If the land-use density were increased, he would benefit from Fairfax County's formula for allowing developers of housing for the elderly to multiply the maximum density allowed on a residential site by four.

The site is located on the northwest corner of Lewinsville and Balls Hill roads, across Balls Hill from the Fairfax Dranesville District office building and police precinct. The site in question is occupied by a trailer used as a satellite tax assessment office while the nearby governmental center undergoes renovation.

Thompson has leased the corner to the county in keeping with regulations, according to a county spokesperson who said such use should not play a role in the current attempt to get Fairfax to approve a higher residential density use of the land.

The proposal calls for construction of housing for the elderly and total life care (nursing home) facilities.

But local residents of affluent nearby subdivisions are upset about the plan, and a large number attended a public hearing to officially oppose it.

The landowner could build elderly housing on the site as zoned but would be unable to build as many units as he would like.

Several residents said they were "not opposed to elderly housing" as long as it is built somewhere else. One woman in the audience who asked not to be identified looked up and said, "I hope those people never get old."

A resident of nearby McLean Knolls, a subdivision of $250,000 houses, said, "I moved here in 1975 because it was a residential area. We want to maintain our residential community. There are a hell of a lot of people here who oppose this. Now they referring to the county have got that damned trailer over there on the site," he said.

Attorney Barnes Lawson said his client is willing to leave the land use under its current designation unless the site is developed for elderly housing. He was speaking to more than 300 people attending a town hall meeting sponsored by the McLean Citizens Association's planning and zoning committee.

"The land will be two-to-three per acre with an option to go higher to five-to-eight if it were for housing for the elderly," Lawson said.

"The current land plan shows two-to-three, but my client wants five-to-eight only if we use it for the elderly," Lawson said.

Lawson said his client would be able to build 240 units at the higher density. He said that is the "ultimate needed for full-service facilities with full life care services." (Full life care services means nursing home care facilities.)

Residents questioned the need for the facility in the particular location, which is opposite the PRC headquarters and the Farm Credit Bureau building along Lewinsville Road. Lawson said it was important for the facility to provide total life care so that residents who develop health problems could continue to live within the same environment.

There are two other elderly residential facilities nearby. They are The Lewinsville near the Presbyterian Church at Great Falls Street and Chain Bridge Road, and inside the renovated former Lewinsville elementary school.

"We are talking about three- or four- story units near $250,000 homes," said Joe Manelski. "Lewinsville Road has got to be the barrier against denser development."

Under the present zoning, the landowner could build approximately 130 units for the elderly depending upon the topography and conditions imposed by the county. Lawson told the crowd he was seeking a change in the land-use plan, not asking for a rezoning and therefore did not have detailed drawings of what the facility might look like.

Even if he had produced such renderings, they would not be binding on either the landowner or the attorney because promises made during a land-use change process are not binding. In Fairfax promises, or proffers as they are generally called, are binding in zoning cases.

When the vote was taken on the plan only about half of those attending voted to oppose the motion, but nobody raised their hand in favor of the motion.

Later, the McLean Citizens Association Board of Directors voted to go along with the zoning committee's recommendation to deny the land-use change on the site.

The housing for the elderly proposal is only one of 300 land-use changes being proposed and talked about in community meetings across Fairfax. The MCA Board voted to oppose 12 of the 14 applications pending in its general area.

Following a close vote by the planning and zoning committee, the board of directors voted to oppose a land-use change in the middle of McLean's central business district, which, if approved, could lead to construction of a luxury hotel complex on a site now occupied by a warehouse and a fast food restaurant.

The full board voted to support the proposed consolidation of five acres in the middle of the central business district near a planned new fire station.

According to Stephen Hubbard, chairman of the zoning committee, his group supports "a comprehensive mixed use of retail/commercial/residential comprised of individual town houses on a residential scale" if the land north of Whittier Avenue, west of Emerson and south of Chain Bridge Road can be assembled.

Also winning MCA approval was a plan by developer Larry Reid to build a small town house development along Dolley Madison Boulevard, near the Summitt Road intersection. The site is surrounded by densely developed detached houses, almost all of which have been built in the last six years.

The board strongly opposed 11 proposals that also have been the subject of a series of public meetings in recent weeks. A citizens' task force, appointed by Dranesville Supervisor Nancy Falck, is holding hearings during the next two weeks on the proposals in her district.

The MCA voted to oppose the following applications:

* A controversial proposal by NV Companies to change the land use of 98 acres along the Leesburg Pike, west of Tysons Corner from residential to commercial. That proposal perhaps has generated the strongest public opposition to any proposed change in the current amendment process.

* A proposal to allow dense commercial development on 10 acres near Dolley Madison Boulevard and Elm Street.

* An application to build a hotel without a restaurant, bar or swimming pool on 3.5 acres at Rte. 7 and Magarity Road, adjacent to the Pimmit Hills community. The applicant wants the land-use plan changed from town house construction to hotel construction. The Pimmit Hills Civic Association this week strongly opposed the plan, saying that construction would severely affect their neighborhood and possibly lead to further commercial encroachment into the residential neighborhood, which is east of Tysons Corner near Marshall High School.

* An application to expand the central business district of McLean by adding 13 acres in the Bryn Mawr and McLean Manor area. Robert Nelson, an area resident seeking to have the land plan changed, said the speculative value of the land is in excess of its residential value; he said that was a justification for changing the acreage from its present residential to commercial designation. Almost 300 residents of the neighborhood have signed petitions opposing the commercialization of their neighborhood. An application by Hazelton Laboratories, which operates under a special-use permit on the corner of Rte. 7 and Towlston Road, to expand its present facilities to allow construction of corporate headquarters. The company, which has offices both in Germany and London, said it would like to double the size of its present facility in order to build a corporate headquarters in a campus environment in Fairfax.

* An application by developer Jim Comparato who is seeking to change the plan for 17 acres along Old Dominion Drive near Spring Hill Road from residential to allow for construction of a neighborhood shopping center and town houses. Part of his site is now occupied by a junk yard. Adjacent land is zoned residential-estate. Home prices in the area easily reach the $450,000 range.

* An application to construct town houses in the $300,000 range on a four-acre site along Dolley Madison Boulevard, adjacent to The Madison of McLean town house development. The site now is occupied by an historic house known as Merry Hill. The house would be preserved under the proposed town house plan.