An alarming number of storage sites under Bay Area freeway underpasses failed state fire marshal inspections spurred by last year’s devastating blaze that shut down Interstate 10 in Los Angeles, according to new Caltrans reports that raise questions about the risks of leasing space under California’s highways. Inspectors found combustible trash, vegetation, tires and debris, stacks of wooden pallets and lumber, unsecured compressed gas cylinders, unsafe wiring, motor oil and obstructed fire safety access. “Inspections of these sites revealed several issues presenting fire or safety risks, as w…