ST. CHARLES COUNTY — A 29-year-old man accused of causing a fatal accident on Interstate 70 Thursday was drunk and driving at least 100 mph at the time of the crash, police said.

The crash killed Robert J. Wood, 51, of Wright City. Wood, a father of five, worked at Boeing as an engineering manager.

Chad E. Frazer, of the 200 block of Mondair Drive in O'Fallon, Mo., is charged with involuntary manslaughter and leaving the scene of an accident.

Police said Frazer's blood alcohol level was 0.27 — more than three times the legal limit — an hour and a half after the wreck.

The crash happened about 12:15 a.m. Thursday as Frazer drove east on Interstate 70 near Bryan Road.

Frazer was driving a 1991 Ford Mustang — going at least 100 mph — in the center lane, said Sgt. Al Nothum of the Missouri Highway Patrol. Wood was driving his 1990 Mercury Topaz in the right lane. Frazer was behind a tractor-trailer and wanted to get around it so he switched to the right lane. That's when he struck the back of Wood's car, west of Bryan.

Wood's car ran off the right side of the interstate. He was pronounced dead at the scene.

Frazer's car ran off the left side of the interstate and hit the median wall. After he crashed, Frazer ran away. He was arrested in a residential area about a half-mile away, Nothum said.

Frazer was treated for moderate injuries at St. Joseph Health Center in St. Charles. He is being held at the St. Charles County Jail in lieu of $100,000 cash-only bail. In 2001, he pleaded guilty of speeding and was fined.

Wood was wearing a seat belt, the patrol said.

"My husband was obeying the law, he was always a conservative driver," Alicia Wood said. "And he was hit by a driver going 100 to 120 miles an hour. They believe the actual impact killed my husband."

Wood's children range in age from 12 to 27. Wood also had a 3-month-old granddaughter.

He was a triathlete, participating in several events a year. He won first place in his age group last year in the Ultramax in Innsbrook.

"He knew the Bible very well, he was quite the Bible scholar," Alicia Wood said of her husband. "He was very fond of rocking his granddaughter."

Joel Currier of the Post-Dispatch contributed to this report.

kbell@post-dispatch.com 314-340-8115