Developer Dwight T. Schar plans to continue his controversial push to build a commercial development on a 98-acre residentially zoned site at the Route 7 and Dulles road interchange despite negative reactions from the Fairfax County planning staff.

Schar, head of the McLean-based NV Land, has asked Fairfax to amend its land-use plan for the site on the northwest corner of the interchange from residential to commercial.

The proposal has come under attack from residents of the McLean-Vienna area because county policy dating back to 1974 has supported the Dulles road as the barrier against expansion of the commercial Tysons area west along the already heavily congested Route 7 corridor.

If the development is approved as planned, the county staff says traffic eastbound on Route 7 could be increased by as much as 30 percent during the peak evening rush hours. The county staff has recommended denial of Schar's proposal but did concede in its final report that the opening of the Dulles Toll Road "would qualify as a significant change in the area" that might affect the land use of the Schar site.

Marshall Coleman, attorney for the project, said that, in spite of the report, the proposal will not be withdrawn before it comes up for public hearing by the planning commission in late April. Dates and times of the hearings will be announced later.

"This is a good plan. This is a good chance to give more than 50 acres to the county," said Coleman, a candidate for the Republican nomination for lieutenant governor.

The comment represents a change from earlier statements by attorneys for the project, even though NV Land has said it plans to leave about 55 acres in open space and has proposed maintaining an existing horse farm on the site.

The development company previously had backed off at public meetings in saying it would be willing to give the land to the county for a park. However, the county is not likely to welcome the land as a park because a major regional park is scheduled to be built about a mile from the site within the next year.

The current development plan, produced by Christopher J. Glaister, a professor of architecture and planning at the University of Virginia, calls for construction of 4 million square feet of office space in low-rise buildings in the center of the 98 acres, which today is primarily open land with farmhouses.

The Fairfax planning staff reports that approval would not be consistent with policy banning "additional industrial or commercial uses" west of the Dulles road.

"The Tysons Corner and Reston areas are planned as major development centers along Route 7, with low-density residential uses planned between them," the staff said.

Approval of this change could "tend to encourage some more development along Route 7," the report said.

According to the staff report, approval of the development would have an "adverse impact" on nearby residential areas and have a substantial effect on traffic, increasing volume on roads well beyond the site.

Coleman said "the site is severely impacted by the Dulles Access Road and the noise problem." In recent public meetings, Coleman said those effects make the land unsuitable for residential development.