Rescue work takes patience. Just ask Pat Cornell.
Since noon Wednesday, the Jersey City firefighter has been shoveling through the ash, picking up each piece of debris, passing it back assembly-line fashion, from the 70-foot pile of rubble that's still smoldering next to the gaping hole that was the World Trade Center.
Acrid smoke and dust, laced with fiberglass and asbestos, billow around the nearby skyscrapers, some dangerously unstable, that hover over the rescue effort. Through the noise of the fire engines, bulldozers, pickaxes, and blowtorches, workers still pause to listen for signs of life.
"If you could picture the end of the world and the people around you are the only survivors, that's it," says Mr. Cornell. "It's havoc."
His yellow firefighter's slicker is covered with dust. He's had two hours' sleep in the last 30. Otherwise, Cornell has been digging through the rubble, "pulling out whatever or whoever, listening for voices. It's not pretty."
He is one of thousands of emergency personnel undertaking the biggest rescue-and-recovery effort in the nation's history. The round-the-clock work is urgent but monotonous - and occasionally, there's hope.
Through the crackle on his radio, Capt. Bill Bokowski heard reports of gunfire at a nearby staging area. At first, they thought it was just ammo exploding in the smoldering debris that sometimes bursts back into flames.
"But it was two cops who were shooting their guns off. That's how they got noticed, and I heard they got 'em out," he says.
They were two of the handful survivors that as of this writing have been pulled from the wreckage. With each day, however, hope of finding more people alive grows dimmer - but not one rescue worker spoken to was willing to stop until they were sure.
And some engineers are fueling their determination to dig through what the Army Corps of Engineers now estimates is the 450,000 tons of debris left from the two towers.
"The steel in the bottom is the heaviest, and that may have helped protect people," says Jack Lebduska, an architect at New Jersey Institute of Technology in Newark, N.J. "There could possibly be many survivors in the subway tunnels."
But danger is present there as well. The subway and train tunnels go as many as three stories down. They're intertwined with gas lines that may still be volatile and water mains and sewers that may have jet fuel in them.
"Gasoline could have washed to the bottom of the building. It floats on water," Mr. Lebduska says.
That's just one of many dangers. On Wednesday, Mr. Bokowski and his crew were working on a part of the building complex that before the planes hit had been in the midst of an asbestos-abatement project.
"We're just covered with the stuff," he says matter-of-factly.
Mike Texter, from Wall Township, N.J., was working near what had been the south tower. He and his fellow police officers were minutes from freeing a body. They'd been down in a hole, using saws, torches, and whatever other equipment they could, when they heard three blasts of a horn - the signal for immediate evacuation. One of the nearby buildings was on the verge of collapse.
"What do you think?" he says, turning to his friend. "Ten more minutes and he would have been out?"
When asked if he himself was afraid of getting hurt, Texter just shrugged.
Indeed, most of the rescue workers had a similar response when asked what motivated them to come and volunteer.
"I don't know. I've wanted to do this all my life, and this is what I've been doing for 10 years," says Cornell.
"Good question!" Bokowski says, laughing. "I don't know."
Some rescuers emerging out of the smoke appeared dazed and just wanted to be left alone. Others stayed close to their colleagues, while they made small jokes and shared sandwiches.
"The hardest thing to gauge is your own response. People react differently," says officer Michael Tomich, who'd just arrived from Irvington, N.J., to help out. "It may be a pain in the neck, it may be monotonous, but your training just kicks in, and you do your job. Then a couple of days later, it hits you what you're doing and what you did."
Federal Emergency Management Agency (FEMA) officials estimate it could take up 60 days - four times as long as the rescue-and-recovery efforts at the Alfred P. Murrah Federal Building in Oklahoma City, which was bombed in 1995. And this is a far more complex operation.
The Murrah Building was mostly concrete, a government office building with hundreds of employees. The World Trade Towers were steel monuments to the financial prowess of America, where 40,000 people worked. Each of the two towers had 35,000 steel columns that are now twisted, mixed with concrete boulders, spread for blocks from the crater.
When the recovery effort is officially over, the cleanup process begins. In Oklahoma City, it took five years to redevelop the area. "There are still buildings down there that are clearly damaged, that you can see," says Maj. Brian Stanaland with the Oklahoma City Fire Department. "Within the last month, the YMCA building was torn down, but it just sat there until last month and was vacant."
When the twin towers were originally built in 1966, the structural steel - all 250,000 tons of it - was trucked in at night over four years' time to avoid tying up Manhattan's traffic. Now, even working around the clock, it's estimated it will take many months - perhaps as long as a year - just to clear the debris.
No one has ventured estimates yet about how much the cleanup will cost. To start, Congress is looking at appropriating $20 billion, some of which would be used for cleanup.
Elizabeth Armstrong contributed to this report.