In our nationwide search for a speaker to discuss the compostability of paper-based food packaging and serviceware, your organization was one of very few instances we found that is actively promoting paper as a compost feedstock. Please can you describe how you entered into this sector?
Windham's food waste composting program started over ten years ago with a farm that takes food waste also including soiled paper and cardboard. Once the District decided to develop a facility closer to the Town of Brattleboro, the existing list of acceptable materials was continued.
WIST: I'm sure the winters must be pretty harsh up in Vermont. Is this a problem for the composting process and, if so, how do you maintain your paper composting operations throughout the winter months?
Bob Spencer: The Windham district composts all year, and in winter months we make the same mixes for food waste, paper, and other bulking agents. However, we construct larger piles to help retain heat, and turn the piles less frequently, also to retain heat.
WIST: We have heard differing accounts of the suitability of paper, paperboard and corrugate as feedstocks for composting operations. In your experience, what benefits and problems have these materials brought you?
Bob Spencer: Paper and cardboard are excellent sources of available carbon, but poor contributors as a bulking agent. We have found that we use approximately one-half as much sawdust/wood chips/leaves, our primary bulking agents, than if we did not have the paper in the food waste loads.
Sawdust and wood chips are commodities and can be expensive for composting operations. By reducing our need by one-half that helps our economics, and we get paid a tip fee for the paper and cardboard.
It also has the benefit of absorbing liquid from the household container, to the collection truck and on the compost pad, reducing leachate.