A report yesterday quoted Loudoun County Supervisor Steve W. Stockman as saying that the Piedmont Environmental Council favored the 5,000-home Ashburn Village project approved by the Board of Supervisors Monday. Arthur B. Larson, an attorney for the council, said yesterday that the council has taken no formal position on the project but has expressed reservations about some aspects of the proposal.

The Loudoun County Board of Supervisors yesterday, in a 6-to-2 vote, approved a controversial 5,000-home development north of Dulles International Airport, the largest such project ever approved in the county.

The Ashburn Village project, which also would contain 2.9 million square feet of commercial space at the site's 1,580 acres near Ashburn, has divided the board because it lies directly under the takeoff and landing patterns for jets at Dulles.

The vote ended two years of debate over the project and followed a compromise between developers and county officials over areas that the Federal Aviation Administration has determined will suffer the largest amount of aircraft noise.

The board's action approves all parts of the Ashburn Village that fall outside current FAA noise zones and approves development in other areas contingent on an FAA decision that noise in these areas will not be as great as expected.

Supporters of Ashburn Village heralded the project as the ideal development, specifically designed to halt suburban sprawl. The developers' proposal called for building homes densely together and agreed to provide several million dollars for road construction and for other services.

"I think it's a good project," said Supervisor Steve W. Stockman. "Everything we've asked them to do, they've been cooperative," Stockman said before the vote. Stockman noted groups that traditionally oppose such development, such as the Piedmont Environmental Council, were in favor of the project.

But Supervisor Ann B. Kavanagh, a consistent opponent of Ashburn Village, said the county's approval of the project sets a grim precedent for the future by allowing developers to build too densely and by leaving open the possibility of development in noise corridors.

Future developers, Kavanagh said before the vote, "can come in and say, 'You gave it to this developer, therefore we want this and this.' "

Much of the Ashburn Village controversy centered on the highly technical concept of LDN, standing for "Loudness Day Night."

LDN measures the total amount of noise a residential area is subject to from aircraft traffic. The Loudoun Board has banned residential development in areas over 65 LDN.

In a study conducted earlier this year by a consulting firm for the FAA, the 65 LDN line dissected Ashburn Village. Morton H. Levine, a spokesman for Ashburn Village, a joint development of Associated Investments Co. Inc. and Richmarr Construction Corp., said that if housing were banned in the 65 LDN area, Ashburn Village would be killed. "It simply would be economically infeasible to make the development smaller," Levine said yesterday.

The developers further contended that the FAA's noise areas were drawn unrealistically, failing to take into account changes in aircraft technology and making unrealistic assumptions about air traffic at Dulles.

"Those lines are ridiculous . . . . They make no sense," said Rosser H. Payne Jr., another developer.

FAA officials, who have sought to discourage residential growth around airports in order to avoid controversies over noise maintained that their estimates of future noise at Dulles were based on the best evidence available.

Kavanagh added that it is virtually inevitable that future residents in the Dulles North area would start to complain about aircraft noise in a fashion similar to controversies at Washington National Airport.

*The developers said yesterday they intend to commission their own study to present the FAA and that they are confident that when new lines are drawn they will be in Ashburn Village's favor.

Voting in favor of the project were Chairman Frank Raflo, Vice Chairman James F. Brownell, Andrew R. Bird III, Frank I. Lambert, Stockman and Betty Tatum. Voting against the project were Kavanagh and Thomas S. Dodson.