State troopers say they found a man passed out on the Interstate 5 shoulder in Mountlake Terrace Thursday morning with a blood-alcohol level at six times the legal limit.

State Patrol dispatchers fielded a call from a witness about 10:22 a.m. reporting a silver Volvo traveling erratically on northbound I-5 near North 145th Street in Shoreline. A trooper in the area searched for the vehicle and found one matching its description in a grassy area off the shoulder of I-5 at 236th Street Southwest, reports indicate.

The trooper found that the driver was unresponsive and left the vehicle running, his foot on the brake and his gear in drive. He put the vehicle in park, turned off the ignition and removed the keys while the driver remained passed out. The trooper called fire department crews, who took the driver to Northwest Hospital, State Patrol reports say.

The hospital later alerted the responding trooper that the driver's blood-alcohol level was measured at .48 percent -- six times the legal limit of .08 percent, according to the STate Patrol.

The driver was identified as a 31-year-old Shoreline man. The trooper found open alcohol containers in his vehicle and took the driver into custody for investigation of DUI.