Traffic was backed up for miles due to a Big Rig over the embankment of highway 49 northbound south of Lime Kiln road shortly before 9 o’clock Monday morning. The driver of a large tractor/trailer hauling long sections of drain pipe was traveling northbound on 49, south of Lime Kiln Rd. The driver allowed the truck and trailer to drift off the roadway and drop down a 40 foot embankment. The driver, who believes he may have fainted prior to the collision, was transported to Sierra Nevada Hospital with minor injuries. Due to the size and location of the tractor trailer, three tow trucks and the use of the northbound lane was required to retrieve the vehicle from the ravine. As a result, the CHP established alternating one lane traffic control on 49 which lasted about 4 hours. Cal-TRans is handling the cleanup of a small amount of diesel fuel which had spilled from the vehicle. The collision remains under investigation.