CHICAGO (AP) -- The Federal Aviation Administration gave the go-ahead Friday for a $15 billion expansion of O'Hare Airport, a project that could ease some of the nation's worst flight delays but cost 2,600 people their homes.
The project -- championed for years by Mayor Richard M. Daley -- calls for new and reconfigured runways, another terminal and parking for oversized planes.
''O'Hare is now cleared for takeoff,'' FAA Administrator Marion C. Blakey said in Washington.
The city had been expecting final approval and had equipment already in place and ready to begin work.
One opponent immediately filed an emergency request with the FAA to halt construction. Critics have fought the project for years because it will require the razing of nearly 500 homes and the relocating of nearly 200 businesses and a cemetery in the suburbs of Bensenville, Des Plaines and Elk Grove Village.
The FAA said the expansion would let O'Hare handle 1.2 million landings and takeoffs a year, 300,000 more than now. Average delays would go from 17.1 minutes to 5.8 minutes, according to agency projections. And it said safety would increase because the new layout would cut in half the number of planes crossing open runways.
The eight-year plan calls for reconfiguring the intersecting runways so that there are six parallel and two diagonal runways. The first runway would open in 2007.
Rep. Jesse Jackson Jr., a Democrat whose district includes Chicago's South Side and southern suburbs, criticized the O'Hare plan, saying it could ''saddle a generation of Chicago taxpayers and travelers with billions of dollars of debt and an airport that's as overcrowded and delay-prone as today's.''
He called for the building of a third Chicago-area airport in cornfields about 35 miles south of the city.
The Becket Fund for Religious Liberty filed the emergency request with the FAA on behalf of St. Johannes Cemetery, which has 1,300 tombs dating back to the 1800s.
''The FAA has done nothing less than authorize the desecration of St. Johannes Cemetery and promote the careless disregard for the First Amendment and federal religious freedom law,'' said Jared Leland, the fund's legal counsel.
Opponents argued the expansion should be stopped because it would desecrate a cemetery with 1,300 tombs dating back to the 1800s.
Chicago has promised that its $14.7 billion plan virtually will eliminate late and canceled flights during bad weather.
Mayor Richard Daley said construction would begin immediately after the FAA gives final approval for the plan, which is expected by September.