POULSBO — A Chimacum man was killed as the result of a single-vehicle crash Wednesday in unincorporated Kitsap County, the Kitsap County Sheriff’s Office said late this afternoon.

Traffic investigators believe that Wayne Dennis Stewart, 41, of Chimacum was driving the 2003 Ford Windstar van that was traveling southbound at a high rate of speed on Columbia Street NE at about 9:30 p.m. Wednesday when the vehicle left the roadway, the agency said in a prepared statement.

The van crashed through a fence and hit a large tree, shearing off the left front end.

The impact partially ejected Stewart and completely ejected a 24-year-old male passenger who was not identified by the Sheriff’s Office.

Stewart was airlifted to Harborview Medical Center in Seattle, where he died, the Sheriff’s Office said.

The passenger was airlifted to Harborview with life-threatening injuries.

His condition was unavailable this afternoon.

Neither occupant was wearing a seat belt, the Sheriff’s Office said.

“Excessive vehicle speed and the consumption of alcohol by the driver of the vehicle appear to have been contributing factors in this crash,” the agency said.

An autopsy on Stewart will be conducted by the King County Medical Examiner’s Office.