By SARA WIDNESS

In spring 2005, Castleton State College (CSC) Professor Paul Derby taught a class on anthropology and the environment. Recycling came into the picture, as the students became aware that Castleton’s recycling efforts could be transformed into a model program.

When the semester ended, the class presented its vision to CSC President Dave Wolk and his cabinet. They suggested first-year students could take an active role in the environment by harvesting recyclables from classroom buildings and residence halls, and delivering the recyclables to a central recycling place on campus.

They then enlisted Casella Waste Systems (CWS) of Rutland, which already was collecting the college’s trash, as a partner in an ongoing sustainability project. Two years later, John Casella, the company’s founder and president, delivered the college’s 2007 commencement address on the theme of sustainability.

“This is a real partnership,” said Ennis Duling, college communications director, noting four classes have now gone through a regimen that’s “now a part of our culture.”

This year, the partnership project has evolved in yet another direction. Before, numerous bins were used to hold waste items of plastic, paper, glass and other materials. Now, just one container will be used, because the college is working with Casella’s trademarked single-stream recycling process, which sorts the containers of multiple bins at the recyclable’s final destination, a Casella facility in the Burlington area.

This process of sorting is called Zero-Sort™ Recycling. Rather than using multiple bins, all recyclables are tossed into one huge container to be hauled to the Burlington repository.

Since the green campus initiative began in 2005, Duling said the college has recycled approximately 100 tons of items, or a volume of slightly more than 2,000 cubic yards. The recyclables have included 3.13 tons of aluminum, 10.5 tons of glass, 10.1 tons of plastic, 6.98 tons of newspaper, 6.2 tons of paper and 63 tons of cardboard.

Duling said students calculated that 100 tons (or 2039 cubic yards in volume) of recycled material has saved 367,350 kilowatt hours; 906.21 barrels of oil, which is equivalent to 20,843 gallons of gas; 975.9 cubic yards of landfill space; and 1296 trees.

Now, the campus community can co-mingle all paper, cardboard, aluminum cans, plastic bottles, tin cans and glass bottles in one bin for collection. When the recyclables reach Casella’s material recovery facility in Burlington, they are sorted by high-tech equipment that uses screens, magnets, blowers and optical devices.

Joe Fusco, vice president of Casella Waste Systems, said single-stream recycling “is a new way to recycle.” Businesses and homeowners have been waiting for a long time for a system that makes it less of a chore to recycle, he said.

“Instead of seven little bins in the garage or mud room, now folks will have one large bin and throw everything recyclable into that bin,” Fusco said. “All of that is then separated mechanically at the recycling facility, rather than being sorted by hand by the consumer or truck driver.”

Fusco said the new technology is “significant in the life of recycling as an activity. If it is so easy, more people will do this and do more recycling.”

The only hitch in this technology is its current availability throughout Vermont, Fusco said, because a municipality needs to have enough residents and business to support investment in new recycling infrastructure.

“We are as a company building or retrofitting these recycling facilities throughout our service area in 13 states from Maine to Florida and as far west as Wisconsin,” Fusco added. The company currently is investing in more densely populated areas such as Boston, Charlotte, NC and Rochester, NY. It currently has eight Zero-Sort facilities companywide, mainly in the eastern U.S.

The sorting process, he explained, involves sorting matter on a conveyor belt, and using machines such as magnets for some metals, or a series of screens that screen out certain things and let others pass by. Also used is an optical sorting system that uses a high-speed camera; a series of high speed air jets based on what the camera sees triggers jets of air at the material, sending milk cartons in one direction and cans in another.

A key to sustainability, he said, is that “recycling has to work at both environmental and economical levels.”

“We’re paddling as fast as we can. This is such a great strategy for increasing the amount of material people recycle,” Fusco said, underscoring the need make it work economically in smaller communities.

Individual towns and communities need to start thinking regionally regarding resource management that can include recycling, police protection, road maintenance and materials purchasing, he noted.