The 50 percent solutiom Wth wet/dry separation, it s achievable

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1 The 50 percent solutiom Wth wet/dry separation, it s achievable by Mindy Gottsegen and Heidi Whitman D iverting 50 percent of residential waste is possible when composting is added to a traditional recycling program. In April 1993, Santa Barbara County, California began an innovative pilot waste collection study that enabled it to identify cost effective and publicly acceptable collection methods capable of achieving 50 percent diversion of residential waste and producing a valuable compost product. The county s approach can set-ve as a model to other communities looking to modify their residential collection systems to increase diversion of wastes from landfills. The Santa Barbara County Pilot Waste Collection Project tested three wet/dry waste separation systems and two collection methods for 1,177 homes across four suburban neighborhoods. The pilot project was part of a planning process undertaken by the Santa Barbara County Solid Waste Management Division to redes@ its entire solid waste management system in response to state legislation requiring 50 percent diversion of the county s waste stream from landfill disposal by the year To meet that goal, the county developed an innovative comprehensive approach to identify the best overa11 system that includes al1 components of waste management system: waste presort, waste collection, delivery, processing, marketing of secondary resources and disposal. Santa Barbara County is located on the south central California coast about 90 miles Autornated trucks collected waste in 63-gallon containers on two of the four routes. north of Los Angeles. Approximately Coast generates about 1,000 tons of waste per 180,000 persons live on the South Coast day, about half of which is residential in oriwhere the pilot project took place. The South gin. Al1 collection is done by private haulers. Mindy Gottsegen was the local coordinator hired by the National Audubon Society for the Santa Batbara County Pilot Collection Project. She is a land use planner and has worked in both New Jersey and California on solid waste and rural planning issues. Heidi Whitman is the solid waste planning manager of the Santa Barbara County Solid Waste Management Division. She is supervising development of the county s integrated waste management system and the South Coast Integrated Diversion Facility. Resource Recycling January 1994 m

2 Single-family residential neighborhoods have twice-a-week backyard collection of municipal solid waste (MSW) and once-a-week collection of recyclable materials. The average monthly fee for this service is $ The purpose of the Santa Barbara Pilot Waste Collection Project was to test altemative methods of waste separation and collection; determine each method s effect on I Table 1 - composting, public acceptance, cost and adaptability over time; determine the quantity and quality of recyclable materials delivered by each collection method; and inspire the residents ownership of the pilot project s results. The Santa Barbara Pilot Waste Collection Project involved primary partners and local sponsors. The primary partners - Santa Barbara County Solid Waste Management Division and the Compost... for Eurth s Suke partnership between the Nation- al Audubon Society and The Grocery Industry - were actively involved with develop- Summary of four routes of the pilot waste collection project Collection Service Type of Size of Number Number ioute Tvpe of separation location Aday.- ~ truck waste cans of cans of homes 1 Two-stream: wet & dry Curbside San-re day Automated 63-gallon 1 wet 239 cm ldry 2 Three-stream: wet & dry Curbside Same day Automated 63-gallon 1 wet 190 & bagged paper (F) ldry 3 Three-stream: wet, dry Backyard Different Manual 32-gallon 2wet(l) 270 & bagged paper days 2dry CM, Tu) 4 Four-stream: wet, dry, Backyard Different Manual 32-gallon 2wet(l) 478 bagged paper & days 2dry bagged recyclables (Tu, F) 1)The actual number of new wet waste cans provided was based on subscribed leve1 of service. Residents used their existing 32-gallon cans for dry waste. jource: Santa Barbara County, California, Pilot Waste Collection Project Interim Report, November ing and administering the pilot project and provided the majority of the staff support and funds. Local sponsors provided valuable support for project implementation. Description of the pilot project The pilot project tested three wet/dry waste separation systems and two collection methods. It began in April 1993, and lasted nine weeks on three routes and ll weeks on one route. Each waste stream was collected once per week. Three of the four routes also involved bagged recyclable materials cocollected in the wet or dry waste stream (see Table 1). Participation in the pilot project was mandatory, but residents who did not separate household waste were not penalized. Field observations and waste sorts were performed to analyze residents success in separating waste and to determine the quality of materials both as they were collected and delivered to the transfer station. Residents opinions and suggestions for improvement

3 were gathered through telephone calls and a mailed survey. Residential collection recovery rates The mandated 50 percent diversion rate is achievable for the South Coast residential waste stream if the best-performing system elements are selected, both recyclable and organic materials are recovered, and available processing technologies are used to create an efficient municipal solid waste management system; however, none by itself will allow the county and cities to comply with the diversion mandate. An average collection recovery rate of 65 percent was achieved across the four routes studied (1). The high was 73 percent recovery and the low was 57 percent recovery. Due to rainfall averaging 180 percent above normal before the pilot project, the volume of yard waste collected was unusually high and had the effect of inflating recovery rates. Residential yard waste was estimated to be at least 40 percent during the pilot period, in c@rast to the annual leve1 of 24 percent projected by the county s 1991 Waste Characterization Analysis. If the extra yard waste is factored n Table2 - Summary of system effectiveness, in percent Two-stream Three-stream Three-stream Four-stream Svstem effectiveness (Th) (1) (F) (2) (M-dq. Tu-wet, (Tu-wet, F-dryl Average Collection recovery rate (3) Normalized for yard waste (iii) (Zx, Recyclable portion (11) (16) Organic portion (38) (42) Mistakes (4) Not sorted 10 (3 (1) Sixty-three gallon carts, curbside, same-day collection. (2) Thirty-two gallon cans, backyard, different-day collection. (3) Collection recovery rate is defined as the capture of marketable materials in the appropriate waste stream. In the wet waste stream, noncompostable materials were picked out; the remainder were considered marketable after composting. In the dry waste stream, only marketable materials were counted. Diversion rate will be lower than the collection recovery rate since it includes processing facility residue loss. (4) Cross contamination. (5) Results of two- and three-stream routes only. Data were not available for the four-stream route. Source: Santa Barbara County, California, Pilot Waste Collection Project Interim Report, November out, a normalized 58 percent average collection recovery rate (68 percent high and 49 percent low) could be expected on an annual basis. (For a comparison of the effectiveness of four routes, see Table 2.) Since the achieved diversion rate will be lower than the recovery rate due to the typical 10 percent processing facility residue loss, then only same-day, curbside placement separation/collection systems would be capable of achieving the mandated 50 percent diversion level. The pilot project confirmed that a compostable organic stream can be recovered in a wet/dry collection system, with collection recovery rates averaging 42 percent at normalized yard waste levels. The recovery of both in-home organic materials and yard waste is necessary to achieve 50 percent residential diversion. The wet streams averaged 94 percent compostable material. Noncompostable materials in the wet stream -Le., mistakes by residents - ranged from 4 to ll percent. These mistakes included tennis sneakers, wine bottles, food cans, milk jugs, film plastic food wrapping, metal shavings and batteries. This contamination leve1 is in line with that found

4 i/ Choose the system components that perform the best. (/ Recover recyclable, yard waste and organic (food and soiled paper) mateli ils. (/ Use available processing technolo- in other wet waste collection systems in North America and Europe. Wet stream composting facilities must be designed and operated to separate these contaminants from the organic materials to ensure production of a marketable compost. Ongoing resident education programs are needed to maintain this performance level. In-home compostables (food and soiled paper) contributed an estimated 24 percent to the normalized recovery rates of the bestperforming system. Recovery of these materials, in addition to yard waste, is required to achieve the diversion mandate for resjdential waste. Recovery of recyclables and yard waste only would provide an estimated residential diversion of just 40 percent. Dry paper in blue plastic recycling bags was co-collected with organic waste on routes using three- and four-stream sorting. The collection recovery rate of marketable recyclables - paper and containers made from glass, plastic and metal - reached 21 percent in the best-perforrning systems at normalized yard waste levels. The recyclable recovery rate is increased by using simpler sorting and collection approaches that lead to higher compliance and fewer mistakes, i.e., more recyclable materials end up in the correct stream for recovery in a processing facility. The two-stream curbside system produced the highest recycling recovery rate at 2 1 percent, and three-stream backyard collection was lowest at 1.5 percent with yard waste normalized. Higher levels of mistakes by residents and collection crews were

5 observtd in the three-and four-stream systems. The use of plastic-bagged paper collection in the three- and four-stream neighborhoods reduced the recovery of marketable, recyclable paper by 30 percent, compared to the two-stream, loose paper collection. Although the pilot project demonstrated that marketable paper, glass and other containers could be collected and recovered from packer vehicles using plastic bags, the recovery rate of recyclable materials dropped, because residents sorted only about 70 percent of the recyclable paper into the plastic bags. Therefore, the decision to use plastic bags for recyclable materials on the South Coast must be based on a consideration of tradeoffs between diversion rates achieved and processing system costs. Collection system Based on results of the pilot project, the bestperforming separation/collection system for the South Coast should include same-day, curbside placement of separated wet and dry streams in uniform, clearly differentiated containers. These system design elements maximize recovery rates by providing stronger signals for habit change to residents and by increasing simplicity for the collection crew. There was a significant difference in normalized collection recovery rate - 68 per- Partners and roles The Compost... for Earth s Sake partnership was formed in 1992 between the National Audubon Society and The Grocery Industry to demonstrate cost-effective solid waste solutions. The Grocery Industry is a coalition of the Food Marketing Institute and the Grocery Manufacturers of America. The partnership was created to assist communities in showing how composting, combined with community recycling programs, can be environmentally sound, politically acceptable and effective in minimizing waste management costs. The Santa Barbara project was the second of a series of Compost... for Earth s Sake pilot projects. The first was held in Greenwich and Fairfield, Connecticut in March Local sponsors that donated time and/or materials to the Pilot Waste Collection Project included the cities of Carpinteria and Santa Barbara, Browning-Ferris Industries, Inc., Heil Corporation, Lucky Stores, Inc., First Brands Corporation, Procter & Gamble Company, Community Environmental Council (of Santa Barbara) and the Santa Barbara Audubon Society.

6 cent versus 49 percent - between the routes that employed same-day, curbside collection in 63-gallon carts and those that incorporated different-day, backyard collection in 32- gallon cans. With expected process residue losses, same-day, curbside collection would deliver 55 to 60 percent residential diversion. The different-day, backyard approach cannot be expected to achieve the 50 percent mandated diversion rate without processing additional streams, with attendant higher operating and/or capital costs. Either manual or automated vehicles could be selected for use at the discretion of individual communities. A diagram of the best-performing system elements is depicted in Figure 1. When outside cans are not uniform in size or clearly differentiated, wet and dry recovery rates can be affected. Without uniformity, collection errors result. System simplicity and uniformity is needed for the collection crew; the color-ceded 63-gallon carts used for aútomated curbside collection worked to meet that need. Involvement of the waste hauler management and crew is critica1 to the success of a new collection system. Involvement of the hauler management in the development of project objectives and system planning fosters project understanding and ownership. The collection crew also needs to understand the objectives of the project and implemen- n Figure 1 -Bes&performing Two-stream. curb nlacement, same day In home Curbside Different containers Vehicle Manual or automatic design elements, wet/dry collection system Three-stream. curb placement, same day DRY Other dry u J DRY Potential WET I DRY WET 1 Bagged recyclables/ DRY Source-separatedl Source-separated processing 1 Dry facility c~;yt$sg IDry processing 1 / 1 c~~;~;~g 1 Recyclables residue processing transfer Products t Compost Paper / Residue Glass Metal Plastic t Compost Paper t Glass Metal Plastic Re Q idue Source: Santa Barbara County, California, Pilot Waste Collection Project Interim Report, November 1993.

7 tation details so they are equipped and motivated to solve start-up problems as they occur on the route. Public acceptance The pilot project created a strong interest and response from the majority of households participating in the project. Over 60 percent of participating households retumed surveys that described their reaction to the pilot project, and 63 percent of respondents offered suggestions for improvement (see Table 3). Participation in the pilot project was mandatory and involved a gmat deal of change for the residents. Although not al1 residents reacted well to change, the majority of survey mspondents indicated that they liked feel- * ing that they were a part of the solution to solid waste problems and that they were helping the county and cities design a cost-effective waste collection system for the future. Achieving high compliance in a sourceseparated system requires carefully planned and continuing education, as is the case for successful curbside recycling programs. Compliance with the wet/dry program reached correct sorting levels over 80 percent - comparable to current county curbside reoycling separation programs. Some degree of resident choice should be maintained in the collection system design. n Table 3 - Summary of public acceptance, in percent Two-stream Three-stream Three-stream Four-stream Pubhc acceutance mh) (1) (F) (2) (M-drv. Tu-wet) (Tu-wet. F-dry) Average Households sorting at least 90 percent of tbeir waste correctly < 60 (3) 73 (4) Questionnaires returned Constructive comments Positive comments 20 ll Negative comments (1) Sixty-thme gallon carts, curbside, same-day collection. (2) Thirty-two gallon cans, backyard, different-day collection. (3) Tl-te four-stream wet waste indicated that 60 percent of households sorted correctly. Although data were not available for the dry waste stream, the dry waste appeared highly contaminated, and considerably less than 60 percent of households sorted correctly. (4) Results of two- and three-stream routes only. Complete data were not available for the four-stream route. Source: Santa Barbara County, California, Pilot Waste Collection Project Interim Report, November It may be possible to provide this by expanding the choice of service fees available. Highdiversion, cost-effective wet/dry systems will require separation of al1 waste into various waste streams and curbside placement of the separate streams for collection. This could be perceived as more work and less service, with no choices left for residents. One way to provide a degree of choice is by expanding the current fee structure to provide a greater range of service options with corresponding costs - from small-quantity/lowfrequency service with lower fees to highquantity/high-frequency service with higher fees. In this approach, even a more costly backyard collection option could be offered. However, each choice must contain the basic components of a uniform approach since fullstream separation is required by al1 residents before 50 percent diversion can be reached. k

8 Collection cost Collection cost is considereb a key élement for public acceptance. In Santa Barbara County, waste management service is paid with a bi-monthly garbage bill. Over 65 percent of the household waste subscription fee is for collection cost; the balance pays for disposal and recycling. Therefore, it is important to minimize collection cost in order to minimize the overa11 cost of waste management. Collection cost effectiveness was built into the collection pilot design by using the constraint of two vehicle passes per week in each neighborhood. This compares with the typical Santa Barbara County arrangement of three vehicle passes per week - one for recycling and two for trash. Plastic collection bags were used to keep co-collected materials separate. Collection stream volumes are best balanced on Santa Barbara s South Coast when bagged recyclable paper and containers are collected in the dry stream and the wet waste is collected alone. Unbalanced loads led to increased costs when extra trips were required to complete route collection. Conclusion The pilot project results provide confidente that a residential wet/dry waste collection system can ensure compliance with the mandated 50 percent landfill diversion forresidential waste in the Santa Barbara South Coast area when coupled with an appropriate processing system. The collection system can be designed to be cost-effective and acceptable to residents in Santa Barbara County. Based on expected source reduction, current and likely markets for secondary materials, and current available processing technology, 50 percent residential landfill diversion can be achieved by adding composting to traditional recycling. If separate collection of wet and dry materials is chosen, implementation should include the best-performing wet/dry collection system design elements: clearly differentiated containers, curbside placement and same-day collection of wet and dry streams. RR Footnote (1) Collection recovery rate is defined as the capture of marketable materials in the appropriate waste stream. In the wet waste stream, noncompostable materials were picked out; the remainder was considered marketable after composting. In the dry waste slream, only marketable recyclable materials were counted. Diversion rate will be lower than the collection recovery rate, since it includes processing facility residue loss. Copies of the final report are available from the Compost... for Eurth s Sake project, National Audubon Society, 700 Broadway, NY, NY 10003; (212) 979-3ooo.