"Bulk transfer/terminal system" means the motor vehicle fuel distribution system consisting of refineries, pipelines, vessels, and terminals. Motor vehicle fuel in a refinery, pipeline, vessel, or terminal is in the bulk transfer/terminal system. Motor vehicle fuel in the fuel tank of any engine, or in any railcar, trailer, truck, or other equipment suitable for ground transportation is not in the bulk transfer/terminal system.
Ca. Rev. and Tax. Code § 7310