The Fairfax County Board of Supervisors clashed yesterday over a major development proposed by the Army at Fort Belvoir, debating whether to limit its size or try to block its construction.

Board Chairman Audrey Moore suggested the Army not develop the land at all because of the development's potential effect on traffic in the area.

"We ought to be preserving it as a park. We cannot take any more traffic in that area," Moore said.

Supervisor Joseph Alexander (D-Lee), whose district includes the part of Fort Belvoir involved, said Moore's suggestion was not an option.

"There is no question the density the Army is asking for is too great. They know that and we know that," Alexander said. "But the Army can do with {the land} what they want."

The Army, which leases 3 million square feet of office space in the Washington area for more than $42 million a year, has proposed building offices on 820 acres it owns along Interstate 95 and Rolling Road in a project sometimes called Crystal City South.

The Army's preferred proposal is to develop 20 million square feet of office, hotel and residential projects on that land, which would create a project about two-thirds the size of Tysons Corner, according to a county staff report.

The county planning staff believes the Army is proposing too much development on the site and has criticized the potential effects on the region's traffic congestion, economy, schools and environment.

The area is largely residential. The Army's proposal would require an amendment to the county's comprehensive plan and a zoning change.

Through a county process called the proffer system, builders routinely agree to build or pay for public improvements in exchange for permission to develop land at higher densities. The federal government, however, cannot be compelled to provide public improvements to ease the impact of its development.

The Army proposes to give land to a developer in exchange for building the project, which would include both private offices and new facilities for the Army.

Yesterday, Moore called for a meeting of Northern Virginia's congressional delegation, a task force of residents and county staff members to discuss the development, but the board said it is too early to get the congressional delegation involved.

In other action, the board requested that staff members study a more aggressive program for collecting delinquent property taxes, modeled after an Arlington program.

The board also voted to use $32 million of the money set aside for construction of the now-shelved Lockheed-Van Dorn Connector highway through Huntley Meadow Park for other county road projects. The money would be used for construction of segments of the Fairfax Parkway between Pohick Road and Rolling Road and between the Dulles Toll Road and Sunset Hills Road.

Staff writer Whitney Redding contributed to this report.