Every day, New Yorkers generate about 11,000 tons of residential trash. Ever since former Mayor Rudy Giuliani (R) shut down the city’s only operating landfill, Fresh Kills, the city has been plagued by the question of what to do with its garbage. For the last year, trash has been hauled on trucks to incinerators and out-of-state landfills. Now Mayor Michael Bloomberg (R) has a new plan: to adapt out-of-use waterfront stations in each of the city’s five boroughs so that garbage can be taken off trucks, packed into containers, and carried away by barge. The plan leaves a lot of questions unanswered — such as, carried away to where? — but it would meet Bloomberg’s goal of reducing the truck traffic that clogs the city streets, damages its roads, and pollutes its air. Bloomberg hopes to have the plan in place within two years, even though he has still not offered an estimate of how much it would cost. “We are not going to continue to give our kids lung diseases, no matter what the cost is,” the mayor said. “That’s the bottom line.”