Under pressure to meet Califor-nia landfill diversion requirements, Santa Barbara County tested alternative methods of residential waste separation and collection.
The pilot project tested two-, three- and four-stream waste separation and manual and automated curbside collection in four neighborhoods. Most of the 1,177 homes studied were suburban, single-family homes on small lots.
Four separation methods (wet, dry, bagged recyclable paper and bagged recyclable containers) were tested in the neighborhoods. Col-lection methods included:
* Same-day, curbside collection. This method was used for the two-stream sort and one of the three-stream sorts. Color-coded, 63-gallon automated carts were provided to residents on this route. Resi-dents placed wet (compostable) waste into green carts while the gray carts contained only dry waste. A driver in an automated side loader collected each load separately at the curb before dumping it at the county transfer station. The driver made two separate passes through the neighborhood and the transfer station.
* Different-day, backyard collection. This collection method was used for one of the three-stream sorts and the four-stream sorts. Green-coded, 32-gallon plastic cans were used for the wet waste and bagged paper; dry waste was placed into 32-gallon cans. A two-person crew collected the cans from residents' back or side yards and emptied them into a manual, rear loader. The different waste streams were collected once a week on separate days.
Several materials that were not listed in the program's educational brochures prompted residents to call the county to find out how to sort items such as extra yard waste, plastic grocery bags, No. 1-7 plastics, cellophane wrap, micro-wave popcorn bags, waxed paper, dental floss and pizza boxes.
Based on the 12-week collection period, same-day, curbside collection of separated wet and dry streams would be the best collection system for the South Coast. To prevent collection errors, containers should be uniform and clearly differentiated. In the future, the county hopes to involve the waste hauler and crew so that they will understand the project and feel a sense of ownership. A more in-volved crew may be motivated to solve start-up problems while en route, according to the study.
The program diverted 55 to 60 percent of waste from residents who had same-day, curbside collection. The different-day, backyard approach will not achieve the 50 percent mandated diversion rate without processing more streams at higher operating or capital costs, according to the study.
To keep costs at a minimum, the county should collect bagged recyclable paper and containers in the dry stream and make a separate trip to collect the wet waste.
When coupled with an appropriate processing system, Santa Bar-bara County officials believe that residential wet/dry collection will bring them into compliance with the state's landfill diversion mandate. Based on expected source re-duction, markets for secondary materials and available processing technology, the project sponsors are confident that a 50 percent di-version rate will be achieved if residents continue to compost yard and in-home organic materials.
The project's primary partners included the County Solid Waste Management Division and the partnership of the National Audubon Society and the Grocery Industry. Local sponsors included the city of Carpinteria, the city of Santa Bar-bara, Browning-Ferris Industries Inc. and the Heil Corp.