National Geographic : 2004 Jun
a vacuum bucket for testing. "The refineries say things are getting better," says Hilton Kelley, at left, "but the numbers don't reflect it." By-products of the U.S. car culture (below) rise from a private dump that the state of Ohio is cleaning up. Until recently the site held 20 million tires, each manufactured with seven gallons of oil. At a California rest stop (below left) truckers save fuel by connecting to IdleAire's yellow tubes for comforts such as AC, phone, and Internet access. Without the hookup they'd have to leave their engines running to get power.