The immediate goal was to rescue survivors and retrieve bodies from the rubble of the destroyed and damaged buildings.

Joe Allbaugh, head of the Federal Emergency Management Agency, flew to New York on Wednesday with New York's two senators, Charles Schumer and Hillary Rodham Clinton, for his first look at operations at the ruined Twin Towers of the World Trade Center.

FEMA has deployed 3,000 workers at the disaster sites, including 12 search-and-rescue teams helping to treat victims and find remains. Displaced families and survivors were being cared for at 27 shelters in the New York City area, and two near the Pentagon in the Washington suburb of Arlington, Va.

After briefing President Bush and congressional leaders on relief efforts Wednesday, Allbaugh said he was ''gravely concerned about victims, brave firefighters and emergency and police personnel who are working so hard in such extremely difficult conditions.''

Veronica Stephens, a liaison to FEMA for the Department of Health and Human Services, estimated that 1,600 people had been treated for injuries as a result of the Trade Center crashes. Forty bodies had been pulled out by afternoon.

FEMA officials would not give estimates for the Pentagon disaster.

Because of the sheer magnitude and nature of the top-down collapse of the Twin Towers, and the size of the debris pile, FEMA operations director Bruce Baughman estimated crews could be on scene for at least 30 days, maybe 60. FEMA crews were on scene for more than two weeks after the 1995 Oklahoma City bombing.

It was unclear how much the two disasters will cost the government. President Bush asked for emergency spending authority Wednesday, and one participant in congressional discussions said the final figure could range between $5 billion and $25 billion.

As of today the 1994 Northridge earthquake was the largest and most costly disaster to which FEMA has responded. Local damages were estimated at $25 billion while federal expenditures were estimated at $12.5 billion including $8 billion from FEMA.

The urban search-and-rescue teams include engineers, medical personnel and specially trained search dogs. One team in New York concentrated on finding victims in the maze of tunnels and shopping corridors beneath the Twin Towers, while two teams were above ground. Five other crews waited nearby to be mobilized, Baughman said. An additional four teams have been deployed to the Pentagon.

As of Wednesday afternoon, officials from Pennsylvania, where a fourth plane crashed Tuesday, had requested no FEMA help. Sixteen other emergency search-and-rescue teams were on standby nationwide.

At least one FEMA mortuary team in New York helped prepare bodies for burial. Experts from the U.S. Army of Corps of Engineers were waiting for clearance to get closer to both disaster sites to help assess structural damage and plan the arduous task of clearing the rubble. FEMA coordinates around 30 federal and volunteer agencies that will back up state and local governments, Allbaugh said.

''FEMA is and will be there to support their needs and will deploy whatever resources are necessary to deal with this tragedy,'' he said before leaving for New York.

FEMA notified government agencies to react to the highest-level emergency, a ''level one'' like those declared after the 1989 Loma Prieta earthquake in California, the 1995 Oklahoma City bombing, hurricanes and severe flooding.

---

On the Net: FEMA: http://www.fema.gov