What is single-stream/commingled recycling? Why does Mason have a multi-stream recycling system?

Single stream, or commingled, recycling is a process of collecting recyclable goods (paper, plastics, glass, etc.) into a single container. In some remote, smaller campus locations (i.e. the Science and Technology campus), Mason follows that process. However, at the larger Mason campuses, Mason requires all students, faculty, and staff to sort white paper; colored paper; cardboard; and glass, cans, and plastics into separate containers. The university has a multi-stream recycling system for several reasons: the university receives revenue for clean recyclable materials where there is a market demand; it keeps contamination low; and it increases the overall environmental benefit of recycling. Mason reviews this practice on a regular basis to determine whether to change it based on environmental and market conditions.