Police said they expected investigators to complete an inspection of the bus and an inventory of personal property and documents on Tuesday.
Oregon State Police identified one of the nine victims as a 57-year-old Washington man. Authorities said Dale William Osborn of Spanaway was killed in Sunday's crash and his wife, Sue Osborn, remained hospitalized in Pendleton.
His daughter, Jennifer Sherman of Colorado Springs, said she was told her father was hit in the head by a rock while her mother was thrown into a river bed.
She last spoke to her father two weeks ago.
"He was very happy," Sherman said. "He's a very good man."
Authorities have not yet released the names of the other eight people who died, but police said the four men and four women were of Asian descent and one female victim may be a juvenile.
The bus was carrying tourists, including some who had been living in Canada, on the final leg of a nine-day tour of the western United States.
State Police Lt. Gregg Hastings said it could take a month or more to determine whether the driver, a 54-year-old man from Vancouver, will face any charges.
State police revised the number aboard the bus to 47 from 48 on Tuesday and confirmed 39 people were transported for treatment of injuries and at least 14 of them remained in hospital.
The Red Cross said some of the survivors were too terrified to get on another bus, so a nearby Ford dealer offered to drive them in smaller passenger vehicles. Some were expected to begin the trip on Wednesday.
Chris Huxoll, sales manager at Legacy Ford in La Grande, Ore., said the dealership will probably use new sport-utility vehicles with four-wheel drive to be sure survivors can safely make the trip to Vancouver.
"We are extremely sensitive to the fact that these kids and adults don't want to get on a bus," said Casey White-Zollman, a volunteer spokeswoman for the Red Cross.
Hastings said Monday that investigators were still trying to confirm the citizenship of the victims but a majority were of South Korean background and lived in British Columbia, Washington state, Oregon and even Idaho.
Police said Tuesday they were working with the Korean Consulate Office in Seattle to make positive identifications, next of kin notifications, and property identification.
A list of injured released by police named seven Canadian residents, including the driver, identified as Haeng Kyu Hwang.
The bus was travelling westbound in the left lane of Interstate 84 when it hit a concrete barrier, veered across both westbound lanes and went through the guardrail before plunging about 60 metres down the embankment, Hastings said. The National Transportation Safety Board said the bus rolled at least once.
When the tour bus came to a rest, terrified passengers looked for their loved ones.
"People screamed and yelled," said Jaemin Seo, a 23-year-old student from Suwon, South Korea, who has been studying in Vancouver. "Some mothers screamed to find their son or daughter."
Seo said he was awakened by screaming and was ejected from a broken window as the bus careened down the hill. He suffered a broken ankle, a gash in his arm and shallow scratches across his face.
The crash occurred near a spot on the interstate called Deadman Pass, at the top of a steep, 11-kilometre descent from the Blue Mountains. Though there were icy spots where the crash occurred, that was nothing unusual for this time of year, said Tom Strandberg, a spokesman for the Oregon Department of Transportation.
He said a sanding truck had applied sand a few hours earlier and was behind the bus making another run when the crash occurred. The sand truck driver was among the first at the scene.
Berlyn Sanderson, 22, of Surrey, B.C., said she also was thrown from the bus.
"It's kind of like one of those dreams you have of the world ending," Sanderson told reporters.
Rescuers faced the challenge of bringing survivors up a steep cliff, Pendleton fire Chief Gary Woodson said. They descended the hill and used ropes and baskets to help retrieve people from the wreckage in freezing weather.
Some survivors were carried on backboards by six or eight rescuers. Others were hoisted in baskets, and an all-terrain vehicle arrived toward the end of the operation, Woodson said.
Yoo Byung Woo, a 25-year-old survivor, said it was snowing and foggy at the time. She told the Oregonian newspaper that one passenger was frightened and asked if they could take another route. Some passengers were dozing when the driver slammed on the brakes.
Yoo said rocks smashed through windows after the bus crashed through the guardrail and rolled down.
Umatilla County Emergency Manager Jack Remillard said the bus was owned by Mi Joo Tour & Travel in Vancouver. A bus safety website run by the U.S. Department of Transportation said Mi Joo has six buses, none of which have been involved in any accidents in the past two years.
— With files from The Canadian Press
Also on HuffPost