RECYCLING

New Practices

Feed It To The Worms

On October 4, 2001, U-M Waste Manage-ment Services became the temporary home to over 50,000 red worms. Housed in a 6-foot by 8-foot unit equipped with an automatic heating and cooling system designed to maintain 65 degrees Fahrenheit, the red worms feast on 50 pounds of food waste three days a week. This vermicomposting unit is being piloted to determine its potential as an alternative method for handling food waste currently collected on campus.

Food waste collection began as a pilot in 1997 with a grant from the Washtenaw County Department of Public Works. With the cooperation of University Housing Dining Services, the staff at Mary Markley, East Quad and South Quad separated the non-meat “prep” waste into special green 32-gallon collection carts that were placed at the loading docks. The carts were then picked up by U-M Waste Management Services and delivered to the Ann Arbor Municipal Compost Center. The pilot ran from August through April and succeeded in diverting nearly 60,000 pounds of food waste. The program has expanded over the last four years to include West Quad, Betsy Barbour and Pierpont Commons. To date over 190,000 pounds of food waste has been collected for composting.

The increasing volumes of food waste collected created an interest in alternative methods for collecting and handling these organics, including vermicomposting systems. During Winter term 2001, as part of the course work for “Sustainability and the Campus”, a group of students with the support of U-M Waste Management Services staff researched vermicomposting options and drafted a paper describing the potential for using this method on campus. An agreement to pilot the Vermiscience unit designed in Fenton, Michigan, was made and one of the writers of the vermicomposting report, Jason Smerdon, agreed to be the “vermiscientist”. Three days a week, Jason, a doctoral candidate in the Applied Physics Program, prepared the food waste prior to placing it in the worm bin for processing. Weights, temperatures and other pertinent data continue to be gathered as part of the project. A harvest of the finished product, vermicompost, will occur in March. A final report of the pilot will follow.

Composting options are of great interest to the U-M community, especially as it relates to waste handling and sanitary water treatment systems. Most food service kitchens dispose of their food waste either by throwing it into the trash or by using a “pulping” process that min-imizes the particle size of the food waste for easy disposal down the drain and into the sanitary water system. Although the “pulping” method diverts the food waste from the trash, it essentially creates a waste problem at the end of pipe. Heavy deposits of food waste into the sanitary water treatment system stress the balance of good bacteria, thereby requiring increased use of chemicals in the water treatment process. Collecting food waste for composting removes these organics from the waste stream and the sanitary water treatment system. This pilot will provide valuable information as U-M Waste Management Services continues to investigate cost-effective methods for handling the many different wastes generated at The University of Michigan.

~ Sarah Archer
Recycling Coordinator