Colin Atagi

Palm Springs Desert Sun

A poorly managed traffic break and two sleep-deprived drivers were identified as the primary causes of a traffic collision that left 13 people dead last year near Palm Springs.

Details were disclosed Tuesday during a National Transportation Safety Board hearing, where investigators presented their findings from the Oct. 23, 2016 collision involving a tour bus and big rig on Interstate 10. And although part of the blame fell on local traffic officials, the bulk of Tuesday's discussion focused on commercial drivers operating on minimal sleep.

“We’re tired, yes we are tired, of seeing commercial drivers being tired,” NTSB chairman Robert Sumwalt said during the hearing, which was live-streamed from Washington DC. “Here’s a case where people just riding on a bus, just paying money to go to casino and back, they died because of destructive sleep apnea on two drivers in two separate vehicles."

ORIGINAL STORY:Thirteen killed in I-10 tour bus collision

The bus was on its way to Los Angeles from Red Earth Casino, near Salton City, when it collided with a big rig trailer on westbound Interstate 10 at Highway 62.

The bus driver, Teodulo Elias Vides, had only four hours of sleep from about 6 p.m. Oct. 21 to the time of the collision at 5:15 a.m. Oct. 23, investigators said. After working overnight, he slept three hours the afternoon of Oct. 22 before driving to Red Earth Casino. He slept one hour before beginning the trip home early Oct. 23.

The bus was moving 75 mph when it slammed into the big rig, which was driven by Bruce Guilford of Covington, Georgia. He's accused of falling asleep after stopping for a traffic break and blocking the road after traffic began moving.

Nearly two weeks ago, the Riverside County District Attorney's office filed vehicular manslaughter charges against Guilford, who is also accused of ignoring a mandatory 34-hour resting period between trips.

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He remained in custody Tuesday at the Newton County jail in Georgia and authorities are in the process of arranging his extradition to California, district attorney's office spokesman John Hall said last week.

Guilford told investigators traffic had stopped for about 30 minutes when it was actually just for four minutes, they said during Tuesday's hearing. Most drivers managed to avoid the big rig, but Vides crashed into it even though he should have been able to see it for about 20 seconds before impact.

The traffic break lasted seven minutes while Southern California Edison crews removed electrical wires that crossed the road from a wooden pole to a steel pole.

A California Highway Patrol officer performed the traffic break and the project wasn't significant enough to require safety measures, such as advance warning signs, officials said. The officer left without noticing a big rig was still in the road.

The effort was "inadequate" and led to a hazardous scenario, said Robert Accetta, who was the investigator in charge.

Caltrans has since implemented a new policy that requires signs and at least two officers participate in traffic breaks: One to conduct it and a second to park in the rear and make sure traffic flows properly once a break is lifted. Caltrans and CHP staff also are required to meet two weeks in advance to discuss planned traffic breaks.

Mechanical issues, drugs, alcohol, weather and distractions from cell phones were all ruled out as factors. Vides had un-diagnosed diabetes and Guilford may have suffered from obstructive sleep apnea.

This led to NTSB officials making recommendations that federal and trucking agencies become more strict when it comes to commercial drivers' health conditions.

Emergency crews responded to the collision in a timely manner, but it took them nearly three hours to remove everyone from the bus. This led to officials discussing whether a second door could have benefited the rescue process, but investigators said that was inconclusive.

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NTSB investigators concluded through their initial on-scene investigation that six of the eight bus tires were overly worn and out of compliance with federal regulations, but the report does not identify the tires as a contributing factor to the crash.

In the past year, at least 10 lawsuits have been filed by surviving victims or family members of the deceased and they're in the process of being consolidated.

Defendants include USA Holiday, Caltrans, Southern California Edison, Riverside County, Palm Springs and Desert Hot Springs. The civil suits mostly blame the defendants for not providing adequate lighting or signage for the roadwork. The accusations are all denied, according to court records.