"In many municipalities around the country, the days of sorting your recyclables for curbside pickup are long gone, replaced by a system called "single stream" recycling. But what happens after all those bits of plastic, paper, glass and metal get put in the bin? Because it's often collected by the same workers who pick up the garbage, it's easy to wonder if the recyclables make their way to the dump, too. But single-stream recycling ends up at a place called a materials recovery facility. An MRF is part warehouse, part industrial plant; a single facility can process hundreds of tons every day, using workers and high-tech machines."