A big rig loaded with office supplies flipped over on a tight turn on Highway 152 (Hecker Pass) Thursday afternoon, dumping its load down a steep ravine. The California Highway Patrol said there were only minor injuries in the 3:15pm incident that forced them and a crew from Caltrans to close the highway to traffic in both directions for more than six hours. The Freightliner truck was traveling west when its right tires slid off the right shoulder. Then the entire trailer flipped onto its side. A crew from Auto Care Towing managed to upright the truck and trailer using a 50-ton and an 80-ton rotator. Cleanup took several hours. CHP officer Israel Murillo said big rigs are not allowed on Highway 152 between Gilroy and Casserly Road, and violations can result in substantial fines.