Speed and not wearing seat belts appear to be factors in two fatal crashes along Interstate 82 that occurred about 11 hours apart this weekend, officials said.
Alcohol also is believed to play a role in one of the wrecks.
A 24-year-old West Richland man and a 21-year-old from Pasco died when they were thrown out of the vehicles they were in during the separate rollover wrecks.
Autopsy results for Trevor Petersen and Michael Hernandez show they died of blunt force trauma to the head, said Benton County Coroner John Hansens. Both suffered fractures to the base of their skulls. Petersen also suffered a spinal fracture, he said.
The autopsies were completed Monday by Dr. Daniel Selove, a forensic pathologist from Everett.
Alcohol appears to be a factor in the death of Hernandez, said Washington State Patrol Lt. Roger Wilbur.
Hernandez was a passenger in a Honda Accord driven by Favian Castro, 21, of Pasco. There were four people in the car.
Castro was driving eastbound on I-82 near Locust Grove Road at 10:30 p.m. when he left the roadway for an unknown reason and rolled down the median. Wilbur said the eastbound lanes of the highway are elevated about 50 to 75 feet above the westbound lanes in that area, which is just east of Kennewick.
Castro's car rolled down the median, onto the westbound lane and ended up on the right shoulder. Hernandez, who was not wearing a seat belt, was thrown from the car and pronounced dead at the scene, Wilbur said.
Another passenger, Lucio M. Mendoza, 22, of Pasco, was treated at Kennewick General Hospital for broken bones. He also was not buckled up, Wilbur said. The third passenger refused treatment.
Castro was treated at Kadlec Regional Medical Center in Richland. Once he was released Sunday, he was booked into the Benton County jail on suspicion of vehicular homicide and vehicular assault.
Earlier Saturday, Petersen was driving near Richland on Interstate 182, taking the interchange to eastbound I-82, when his Chevrolet Blazer went off the road and rolled.
Speed is likely a factor, but Wilbur noted Petersen might not have been speeding, but he was driving faster than he should have been to safely take the curve.
Petersen also was not buckled up, he said.
Both crashes remain under investigation.
Troopers in the region, which stretches from Yakima to Asotin counties, also had to investigate a double fatal head-on crash in Asotin County late Friday.
The collision occurred when two Jeeps tried to pass another car that was driving eastbound on Highway 12 from Pomeroy when they came upon a car in the westbound lane, Wilbur said.
The driver of the first Jeep was able to swerve onto the shoulder to avoid the car, but the second driver had no time to react and slammed into the car. Both drivers were killed. The driver of the Jeep is suspected of being under the influence of alcohol, Wilbur said.
Wilbur said motorists need to follow three basic rules to prevent deadly wrecks on the highway: "Don't drink and drive, slow down and wear your seat belt," Wilbur said. "It's the same old mantra, I guess, but some people aren't paying attention."
-- Paula Horton: 509-582-1556; firstname.lastname@example.org