Community and Municipal Composting

On account of the confluence of a number of ecologically and economically limiting factors along with considerable social pressures, a number of urban municipalities have taken the steps to begin city food waste collection and composting programs.  A considerable range of approaches have been taken to address the need for municipal composting.  These have included large waste handling corporations such as Waste Management expanding the range of their services, mid-range haulers bringing food scraps to regional composting facilities, and “micro-haulers” or community-based composting initiatives working primarily within ciy limits on small parcels of land (Schaffer, 2016).

Despite its importance the importance of composting, however, many cities (particularly smaller and less affluent municipalities) have been slow to act in implementing city-operated programs.   In response to the inaction of municipal governments, and from a desire to prevent large corporations from dominating the composting industry, a number of community-based, citizen sponsored compost collection initiatives have begun.  Collecting food wastes from both residents and businesses, these groups are utilizing vacant lots and community gardens to transform food wastes into soil (Herrmann, 2016 ).

Community-based composting has many advantages over larger scale municipal compost collection and mid-range haulers.  Perhaps the most significant of these is the amount of energy and greenhouse gases that are spared by handling the collection and processing of compost locally.  Transporting food wastes long distances increases the “food miles” travelled by foods, a metric used to measure the benefits of eating locally (Weber, 2008).  When food waste is collected and then transported many miles out of a city to a large commercial composting facility, commonly with diesel powered trucks, enormous amounts of carbon-based fuels are combusted.  Depending on the total distance driven, this energy consumption could negate the reduction in greenhouse gases achieved by separating organics in the first place.  If micro-hauling operations move food wastes with bicycle carts or electric or biofueled vehicles, it may be possible to even further reduce greenhouse gas emissions associated with composting.  Small-scale composting techniques employed by micro-hauling operations also do not rely on the large energy intensive turning or tumbling machinery employed by large composting facilities.   Adding to the benefits of community-scale operations is the fact that even more energy and carbon are saved again when finished compost is used within city limits, rather than transported back into the city from a distant facility.  In order to even further reduce energy expenses associated with composting, it would be sensible to carry out composting operations on even smaller scales in large cities, conceivably with each neighborhood being responsible for composting its own wastes.

Community scale composting operations can also produce compost that is of a better quality than municipally produced compost.  Municipally produced compost often contains a variety of contaminants such as plastic bags, polystyrene cups, etc.  Many of these originate from curbside collections of yard rakings, which will contain debris that home owners neglect to remove.  These non-organic particles can end up in the finished compost product, which may be permitted to have as much as two-percent of its weight comprised by contaminants.  Fragments of shredded plastic bags throughout compost is visually unappealing, and could result in unknown health effects (Rich, 2007).  When food wastes are processed on a smaller scale by non-mechanized means, it is easier to screen out non-compostable materials.  A handful of studies have demonstrated that small-batch compost is as good or superior in overall quality to industrial composts (Farrell, 2010)(Barrena, 2014).

Advertisements