LAKEWOOD, Colo. — First, it’s important to remember that investigators have not said what they believe caused Thursday’s crash on Interstate 70 that killed four people.

But after reviewing video, some truck drivers and Commercial Drivers Licence (CDL) instructors familiar with the area where the crash occurred have expressed concern about the semi-truck driver’s speed and whether the driver from Texas had much experience driving in and out of Colorado’s high country.

Four people were killed and several others were injured in the pileup on I-70 and the Denver West interchange that caused a fire so intense that it melted the roadway and metal off of cars. Police said the crash involved at least 28 vehicles, including 24 cars and four semis. 

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Lakewood police said semi-truck driver Rogel Lazaro Aguilera-Mederos, 23, of Houston, Texas, caused the crash. He has been taken into custody on four charges of vehicular homicide, police said. 

Rogel Lazaro Aguilera-Mederos
Rogel Lazaro Aguilera-Mederos
Lakewood Police Department

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The crash happened after the truck dropped out of the mountains, headed eastbound on I-70 toward the Denver West exit. Highway signs miles ahead of the crash site warn truckers of “steep grades and sharp curves to go.”

“If you’re coming down the mountain properly, brakes never get hot,” said Jason Emery, CEO of EXCEL Driving Services in Henderson. “If you’re coming off the mountain it should be boring. You should barely be touching your brakes. It should be holding its way through.” 

Video from moments before the crash shows the semi barreling toward the Denver West Exit, speeding by traffic. Investigators say the driver from Texas did not and could not stop. Emery wonders about his training.

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“If he didn’t get training, I feel bad for him. Because the mountains are nothing to mess around with,” Emery said. “If you do everything right you’re going to be fine. If you don’t you’re really taking a significant risk.”

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At EXCEL students repeatedly practice various driving scenarios in a simulator and then again out on the road. Repetition, Emery says, is the name of the game and Colorado’s mountains are a far cry from the Texas flats.

Emery said he will look out for what investigators find. What kind of training did the driver have? How much experience did he have navigating mountainous terrain?

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St. Anthony's Hospital said it treated 10 people for injuries following the crash. The people who died have not been identified yet.

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