(Portland, OR)  --  A 19-year-old man is facing multiple charges after allegedly crashing into a semi trailer and then fleeing the scene, leaving his injured passenger behind.  Police Julio Bautista Montella was high on marijuana when he crashed into the semi trailer in Gresham earlier yesterday morning.  He then allegedly fled the scene on foot, leaving a woman trapped inside the wrecked car.  First responders extricated her from the vehicle and took her to a hospital with possible life-threatening injuries.  Police arrested Montella for hit-and-run, DUII and several other charges.