DENVER -- Authorities said it may be days before investigators sort out the chain of events in a fatal pileup involving up to 75 vehicles.

The accident on Interstate 70 left one person dead, injured 22 others and closed the highway for nearly eight hours. Five people remain hospitalized Monday.

Colorado State Patrol Trooper Gilbert Sullivan said the accident happened Monday afternoon during snowy weather.

He said a semitrailer jackknifed and a man driving a Kia Sonoma couldn't stop and slid underneath the semi, shearing off the top of his car. The patrol said Lance Melting, 39, was the driver of the Sonoma. He died from injuries Monday.

From there, it was chain reaction after chain reaction as cars continued to crash into the wreckage. Two hours later, cars were still skidding into the wreckage and the total count of damaged vehicles had climbed to about 70, according to the state patrol.

"The conditions were just horrible at that time," said Master Trooper Ron Watkins with the Colorado State Patrol. "There were white out conditions, the roads were slick and there was poor visibility."

The accident forced travelers to find lodging in the mountain communities on either side of Vail Pass. Authorities spent the evening busing drivers caught in the pileup to nearby towns and clearing the dozens of tangled vehicles from the westbound lanes of the highway.

Kenny Griffin was one of the last people to make it over Vail Pass when he saw the crash.

"It was just a big pinball wreck," Griffin said.

Griffin said he saw six semitrailers-- two of them jackknifed -- at the front of the wreck with at least a dozen of cars jammed in-between. There appeared to be a second group of crashes farther behind, he said, with cars upside-down and pinned under one another.

The interstate was reopened in both directions Monday night.

This year is shaping up to be a costly one for CDOT. CDOT spokeswoman Stacey Stegman said I-70 has been partially closed for about 298 hours this season. It was closed 203 hours last year.

"I have chained up 18 times this year, actually 17," said truck driver Phil Port. "Last year, I chained up once." "I haven't seen a winter like this in ages," he said.

Stegman said CDOT anticipates spending $71 million on snow and ice removal. It had budgeted for $43 million.

"We have never had a winter like this," she said.

The crash occurred at about 1:20 p.m. I-70 wasn't fully reopened until 9:50 p.m.

Because of the magnitude of this episode, CSP said it will take investigators at least two days to sort out the change of events and generate a complete report.