CHICAGO (CBS) — For the first time we’re hearing from a driver who survived the fiery crash that shut down the Eisenhower for hours.

CBS 2’s Jeremy Ross has the story from Melrose Park.

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Seven investigators from the National Transportation Safety Board are on site.

Their mission is to determine exactly why it happened and how to prevent it in the future.

“I just remember hearing truck trailer locking up the breaks hard,” says Todd Pasteur, who’s SUV was hit in a multi-car collision Thursday.

He’s physically unharmed. But emotionally shaken at what he saw.

“Tires started blowing and there were explosions. We tried to get that person out of that car,” says Pasteur.

That person was 37-year-old Christopher Follett who died in the collision.

Follett’s wife Megan calls him a committed uncle to six nieces, passionate about news and current events and a loving husband.

“I tell him every day ‘you’re so nice I don’t deserve you’,” says Follett. “And he would always shoot back ‘no you’re so nice. I don’t deserve you.'”

The NTSB on site at a tow lot reviewing what remains of the crash.

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Investigators say the chain of impacts began when traffic on I-290  slowed suddenly.

Two semis and a car were stopped.

The driver of a third semi didn’t slow down and hit the car, forcing it underneath the semi in front of it.

That semi hit the first semi.

At the same time, the second semi’s trailer veered into the middle lane causing a chain reaction crash with three more cars.

Pasteur with the help of a truck driver and others they were able to save one driver.

“”He came over and broke the back window. (I) opened my knife and I cut out her air bag so she could climb out,” says Pasteur. “That car went up in flames  probably 30 seconds after she got out.”

Two drivers were cited with failure to reduce speed.

The NTSB says it will be about a month before we could see preliminary results of their investigation.

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The full investigation may take about a year to look into.