The story...

The passport of one of the hijackers was found at the WTC. It's clearly impossible for any personal effects to survive the impact and explosion, therefore it must have been planted.

Our take...

Our first reaction is why would they bother? What does it add to the story? There was no need to “plant passports”. We’ve never seen anyone say “they must have been on the planes because look, the NYPD found that passport”. It’s completely unnecessary, and is only ever used as evidence of an “inside job”.

But could the passport have escaped destruction? Explosions are unpredictable things, it’s surprising what can survive, and there are accounts of personal effects being retrieved from other passengers. Here’s one from Flight 175.

"Orange County, CA., Sept. 11 - Lisa Anne Frost was 22 and had just graduated from Boston University in May 2001 with two degrees and multiple academic and service honors. She had worked all summer in Boston before coming home, finally, to California to start her new life. The Rancho Santa Margarita woman was on United Flight 175 on the morning of Sept. 11, 2001, when it became the second plane to slam into the World Trade Center...

Her parents, Tom and Melanie Frost, have spent two years knowing they will never understand why.

A few days before the first anniversary of our daughter's murder, we were notified that they had found a piece of her in the piles and piles of gritty rubble of the World Trade Center that had been hauled out to Staten Island. It was Lisa's way, we believe, of telling us she wasn't lost.
  
In February, the day of the Columbia tragedy, we got word they'd found her United Airlines Mileage Plus card. It was found very near where they'd found a piece of her right hip. We imagine that she used the card early on the morning of Sept. 11 to get on the plane and just stuck it in her back pocket, probably her right back pocket, instead of in her purse. They have found no other personal effects".
http://216.239.59.104/search?q=cache:tI2PQRqfJiIJ:www.msnbc.com/local/MYOC/M324557.asp

It’s a card rather than paper, and wasn’t ejected from the building, but this does demonstrate that not everything was incinerated. And it’s not alone. There are similar reports from the other crash scenes, including a drivers licence and luggage tag recovered from Flight 77 and even more from Flight 93.

United Airlines Flight 93 slammed into the earth Sept. 11 near Shanksville, Somerset County, at more than 500 mph, with a ferocity that disintegrated metal, bone and flesh. It took more than three months to identify the remains of the 40 passengers and crew, and, by process of elimination, the four hijackers...

But searchers also gathered surprisingly intact mementos of lives lost.

Those items, such as a wedding ring and other jewelry, photos, credit cards, purses and their contents, shoes, a wallet and currency, are among seven boxes of identified personal effects salvaged from the site.
http://www.post-gazette.com/headlines/20011230flight931230p3.asp

There’s some support for the idea from other crash sites, then, but of course surviving the initial impact is only one problem. Others ask how could one passport be recovered so quickly from the rubble of the trade centre collapses? Fortunately the answer is a simple one. It wasn’t. Here’s the official account of what happened.

The passport was recovered by NYPD Detective Yuk H. Chin from a male passerby in a business suit, about 30 years old. The passerby left before being identified, while debris was falling from WTC 2. The tower collapsed shortly afterwards. The detective then gave the passport to the FBI on 9/11.
Page 40
http://www.9-11commission.gov/staff_statements/911_TerrTrav_Ch2.pdf

The suggestion here is that the passport was found amongst the debris on the street. 
Other accounts certainly suggest some parts of the plane were left outside the building.

On the ground, they saw an odd shape. Reiss looked closer: It was the nose gear of an airplane...

A part of the landing gear landed five blocks south
Page 20, “102 Minutes”
Jim Dwyer and Kevin Flynn

After the first crash, the debris, plane parts and body parts were all over the area. 
http://zibili.com/sept11/91103.htm

This photo is particularly interesting.


(Download the full-size version by clicking here).

As you can see, there’s debris on the ground, but not piles of it. A passport would stand out.

Better still is the caption of the photo on its original page: “On Albany Street, two blocks south of WTC 2, Two men examine a seat cushion from AA Flight 11. 8:52 a.m”. A cushion, from Flight 11? An eminently flammable object that was passed through the building, still recognisable, rather than burned to ashes? Plainly we can’t prove the caption is correct, although it would explain why two passer-bys have stopped to look (an ordinary cushion from the building probably isn’t going to attract the same attention). 

Meanwhile another story in the New York Times said at least two items of mail on the 9/11 planes were recovered:

On Oct. 12, it arrived inside a second envelope at Mrs. Snyder's modest white house on Main Street here, and the instant she took it out and saw it, she says, ''chills just went over me.'' It was singed and crumpled. A chunk was ripped out, giving the bottom of the envelope she had sent the look of a jagged skyline. Mrs. Snyder's lyrical script had blurred into the scorched paper. The stamp, depicting a World War II sailor embracing a woman welcoming him home, was intact.

Along with the letter was a note: ''To whom it may concern. This was found floating around the street in downtown New York. I am sorry if you suffered any loss in this tragedy. Sincerely, a friend in New York!''

Since then, Mrs. Snyder, a customer service representative at a grocery store, has discovered that she has one of only two pieces of mail known to have been recovered from the planes that crashed into the World Trade Center. At least one auction house has contacted her, saying she could sell the letter for tens of thousands of dollars.

One Letter's Odyssey Helps Mend a Wound
New York Times
December 20, 2001

What else was on the street, and why couldn’t a passport have made it intact?

If you’re still not sure, preferring to go with intution and say survival was impossible, then consider this story from the Columbia Space Shuttle disaster. The craft broke up on re-entry, 40 miles about the earth, and debris fell over a wide area. Amongst this was one of the experiments involving tiny worms.

The worms and moss were in the same nine-pound locker located in the mid-deck of the space shuttle. The worms were placed in six canisters, each holding eight petri dishes.

The worms, which are about the size of the tip of a pencil, were part of an experiment testing a new synthetic nutrient solution. The worms, which have a life cycle of between seven and 10 days, were four or five generations removed from the original worms placed on Columbia in January.
http://www.space.com/missionlaunches/sts107_worms_030501.html

Remarkably, not only were the canisters retrieved, but the worms were still alive (the above link tells you more). Who would have believed that? Not the scientist in charge of the experiment, who said in the same story:

``It's pretty astonishing to get the possibility of data after all that has happened,'' Sack said. ``We never expected it. We expected a molten mass.''

 In fact if we wanted to start a “Columbia space shuttle crash never happened” conspiracy site then that would make great “evidence”, because it goes against what you’d expect. And there’s a great quote, too. But then maybe intuition doesn’t tell the whole story, and more can survive explosions than you think.