The truck's driver was going too fast, officials said, which caused the truck to jack-knife at the Red Narrows, one of the canyon's sharp turns. The truck tipped over, skidded across the pavement and started a fire on the mountainside.
The flames reached the explosives and sparked a massive explosion just before 2 p.m. Wednesday, leaving only the truck's engine block and a mangled axle. The blast carved a hole in the road 30 feet deep and about 70 feet wide and propelled concrete barriers into the Spanish Fork River hundreds of yards away.
The force of the blast also sent out concussion waves that shattered windshields and crumpled car frames and left many of the witnesses with temporary hearing loss.
Motorists who stopped to help the driver out of the burning truck began running or driving away after one driver told people at the scene that the semitrailer truck was carrying explosives. At least 10 people were injured when the truck exploded.
The truck had picked up its load shortly after 1 p.m. at Ensign-Bickford Industries, an explosives company in Spanish Fork, and headed up the canyon with a shipment bound for Oklahoma.
Troy Lysfjord of Blackfoot, Idaho, a passenger in the truck carrying the explosives, was transported via helicopter to Utah Valley Regional Medical Center in critical condition. He was later upgraded to fair condition and is expected to be released today.
The truck's driver, Travis Stewart of Rexburg, Idaho, was flown by helicopter ambulance to University Hospital. He was in fair condition Wednesday night.
The exact number of injuries is unknown because some of the individuals drove themselves to hospitals with minor injuries, such as cuts or bruises, said Utah Highway Patrol trooper Jay J. Przybyla. In addition to UVRMC, patients were treated at LDS Hospital, the University of Utah Medical Center and hospitals in Payson and Price.
Six were at Castle View Hospital in Price. All were treated for minor injuries and released. At LDS Hospital, the driver of a car behind the truck, Art Rigoli, was treated for minor injuries and released.
Lysfjord was the co-driver and has been professionally driving a truck more than five years. The driving partners have gone through the canyon numerous times, Lysfjord said. He was trying to get some sleep in the back of the cab when the truck rolled.
"I could feel it lean to the right . . . ; the next thing I knew I was being slammed" against the cab, he said. That's when he received most of his injuries, which were cuts and scrapes.
He found Stewart, whom he calls a friend, and helped get him out of the seatbelt. Stewart ran from the truck and Lysfjord followed.
Lysfjord estimates that about 3 minutes passed between the rollover and explosion. He was about 75 yards away. He was in and out of consciousness in the canyon but said he tried his best to warn people to get away, maybe at the expense of his own safety.
"I spent way too much time trying to get people to move. They didn't move fast enough," he said. "That's hard to do when people don't listen. They're just curious, I guess."
Mapleton resident J.D. Herbert, who was treated for injuries at UVRMC, was traveling through the canyon and was thrown off his motorcycle by the explosion. He tried to seek shelter behind a minivan.
"The mom was screaming and her kids were crying," Herbert said. "Shrapnel (was) hitting the forest and crackling like bacon."
In all, eight people sought treatment at the Provo hospital, said Janet Frank, spokeswoman for UVRMC.
"The blast was hard enough to blow out windows," Utah Highway Patrol Sgt. Al Christianson said. "That's pretty significant."
He compared the blast to a war-zone-type incident, and the site was still being monitored for undetonated explosives into the evening.
The explosive devices that were in the truck small orange tubes nearly 10 inches long are used in seismic exploration and are normally safe. However, the intense heat of the fire was too much, and all but 60 pounds exploded, said UHP Lt. Kenneth B. Peay.
The truck was following federal regulations, according to the Utah Department of Transportation and company officials.
"It is up to the United States Department of Transportation to regulate and issue permits, but as far as we know, this truck had the necessary permits to carry whatever it was carrying," said Nile Easton, spokesman for the UDOT. He said rules and regulations pertaining to the transport of hazardous materials are left up to the federal government to ensure uniformity across the states where big rigs travel.
Because of the blast, the highway is impassible, and nearby railroad tracks were bent like pipe cleaners. There is no timeline yet as to when the tracks will be ready again. The line is used by Union Pacific Railroad, Amtrak and for coal transportation.
Amtrak officials said they are holding a passenger train in Grand Junction, Colo., that would have had to pass through Spanish Fork Canyon.
Paul Crespin, manager of track maintenance for Union Pacific Railroad, has been working on the line for 34 years and said he had never seen anything like this accident.
"It's not good," he said after returning from the blast site. "Not good at all."
Construction crews were on the way up the canyon by early evening with the goal of opening the road by this weekend, said Brent Wilhite, Utah Department of Transportation spokesman.
"Our number 1 goal is to make sure the area is safe," he said. "We will work around the clock to get this road open ASAP."
UDOT will use its emergency funds to repair the road, but once everything is fixed, Wilhite said, there will be talks with the company's insurance group about restitution.
However, construction crews will not just be focusing on clearing, refilling and repaving the road. They also must create support for the side of the mountain.
The blast shaved the mountainside, sending car-size boulders down on the road, and ignited several small fires.
On top of the mountain, the blast also knocked down three power poles, disturbing phone service for the surrounding area. Scofield was the largest town affected.
Helicopters circled the area Wednesday afternoon, giving county crews a different look at the devastation. UHP pilot Steve Rugg had recently returned from serving as a pilot in Afghanistan and said this damage was incredible, much more damaging than anything he saw during the war.
"I never saw bomb craters as big as that one," he said.
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