Scott

September 22, 2005 | General

COMPOSTING COMES BACK TO THE BIG APPLE


BioCycle September 2005, Vol. 46, No. 9, p. 29
With curbside collection service restored last fall, New Yorkers are diverting yard trimmings and taking advantage of compost give back events.
Rich Flammer

“WE HAD an average of 250 people per day at our compost giveback events and they were ecstatic. My staff working the events remarked they’ve never seen so many happy New Yorkers in one place at one time,” observed Robert Lange, Director of New York City’s Department of Sanitation, Bureau of Waste Prevention, Reuse and Recycling (BWPRR). Although compost giveaways have always been popular, Lange was impressed at the enthusiasm exhibited by residents after the City’s curbside collection and composting program for yard trimmings restarted in the fall of 2004, after a two-year absence. Budget deficits had led to the suspension of the program.
New York City formally began composting in 1990 with a pilot project at the now closed Edgemere Landfill in Queens. One thousand tons of leaves were processed at the time, the embryonic start to a program that expanded into diverting about 30,000 tons a year of organic materials including leaves, grass clippings and Christmas trees collected from or dropped off by residents and City institutions; yard trimmings delivered by private landscapers; and food residuals processed from Riker’s Island prisons. The City also had fortified its diversion efforts with public education programs and pilot projects assessing various composting technologies and diversion strategies. BWPRR has had to explore a multifaceted approach to organics diversion to make it work. Commingled collection, small scale on-site composting, intensive public education programs, and source reduction strategies have all been studied, piloted, or implemented in the past 15 years. While the suspension of New York City’s yard trimmings collection was a disappointment, it didn’t appear to set back reinstatement efforts, and just months after starting up again, the same programs fine-tuned through years of work are in full swing.
RESIDENTIAL AND INSTITUTIONAL COLLECTION
The Department of Sanitation collects, free of charge, both garbage and source separated recyclables from residences and public and nonprofit institutions. The five boroughs of New York City – Manhattan, Queens, The Bronx, Staten Island, and Brooklyn – are divided into 59 administrative districts, which share the same boundaries as named communities, such as Park Slope, Flatbush, Chinatown, SoHo, Battery Park, and so on. Yard trimmings collection is provided to 37 administrative districts in the four boroughs outside of Manhattan, but not in Manhattan itself. Collection first began in all three districts of Staten Island in 1990, and was expanded in 1997 to five districts in the Bronx after the Mayor’s Task Force Report recommended closing the Fresh Kills Landfill. Unfortunately, citywide collection was suspended in 2002, just a short time after BWPRR brought online every district generating substantial volumes of yard trimmings that was identified as feasible to receive the service.
Prior to a pilot schedule in 1998, yard trimmings collection was provided to residents the day after recyclables (paper and metal, glass, plastic, etc.) were picked up. The existing “day after” schedule proved to yield low truck efficiencies, with an average of 4.8 tons collected per truck. It was also found to be confusing for residents, and yard trimmings had relatively high contamination rates. The pilot collection schedule tested in the fall of 1998 had residents place leaves at the curb on three alternate Saturday evenings for collection from midnight on Saturday to Monday morning, a time period when normally no materials are collected citywide. “The new schedule worked beautifully,” recalls Lange, as weekend collections resulted in a dramatic increase in truck efficiencies, with an average of 7.2 tons/truck; contamination was almost completely eliminated. The collection service resumed in the fall of 2004 utilizes the same, efficient weekend collection schedule. Residents place leaves, small pieces of brush, etc. in plastic bags that are collected by Department of Sanitation packer trucks. Public and nonprofit institutions, such as schools, parks, and government buildings, receive the same services.
LARGE-SCALE COMPOSTING IN THE CITY
New York City currently has two large-scale composting facilities, one located at the closed Fresh Kills Landfill on Staten Island, and one in Soundview Park in the Bronx. The Fresh Kills Compost Facility, with 24 permitted acres, opened in 1990. Yard trimmings from Staten Island, Brooklyn and Queens are delivered to this site. Private landscapers may deliver there as well, paying $10/cubic yard. Tonnages of leaves and mixed yard trimmings (grass, weeds, shrub trimmings and small branches) have increased since the site first opened. In 2004, the facility accepted 6,600 tons from private landscapers, up from 5,600 tons in 2000, and 11,800 tons of leaves, up from 7,300 tons in 2000. During the suspension period, Fresh Kills continued to operate on a smaller scale, receiving only mixed yard trimmings (a total of 12,800 tons from 2002 to 2003) from private landscapers. The facility also processed 800 tons of Christmas trees from the winter of 2004/2005.
Soundview, with seven permitted acres, accepts only leaves collected by the Department of Sanitation from the Bronx and Queens. It is part of an agreement BWPRR has with New York City’s Department of Parks (DOP). In 2004, Soundview received 5,800 tons of leaves, up from 3,600 tons in 2000.
Implemented in 1997 after a Memorandum of Understanding was signed, the land agreement allows BWPRR to use vacant or undesirable parkland to temporarily operate composting facilities in return for supplying compost to DOP for environmental restoration, beautification, and general maintenance of City parks. BWPRR has identified another parcel of land under the program, and a proposed 19.6-acre compost facility, located in the Spring Creek community in Brooklyn, is in the process of being permitted.
The City’s two active facilities, both managed by Organic Recycling Inc. (ORI) of Tappan, New York, employ an open windrow composting process. Leaves (and grass at the Fresh Kills facility only) delivered in plastic bags are debagged using a trommel screen with blades. The shredding action of the blades opens the bags and reduces the particle size of leaves. The Fresh Kills site has a McCloskey trommel; there is a ReTech screen at the Soundview site. While shredded pieces of plastic remain in windrows throughout the process (about 90 percent of the bags come out in the debagging/screening step), final 3/8-inch screening (done with the trommel screen as well) removes them and any other physical contamination. The finished product is black, crumbly, and enormously popular with residents.
Soundview’s windrows are aerated with a Frontier compost turner, while Fresh Kill’s are turned with a front-end loader. At both sites, lime is used to control odors, and supplemental nitrogen is applied to improve the C:N ratio of composting leaves. Each windrow is turned between one and three times per week for six to seven months. Once compost receives a final screening, it’s cured for a month and ready for distribution.
Brush, tree parts and logs received at Fresh Kills are ground with a Precision Husky ProGrind. The chips are used with leaves as a bulking agent for grass.
FOOD RESIDUALS COMPOSTING ON RIKERS ISLAND
The home of five New York City prisons, and the largest municipal prison system in the United States, Rikers Island houses some 17,000 inmates and 700 officers. Originally 87.5 acres when purchased in 1884, the site slowly grew to its present size of 415 acres after it was used as a landfill between the time it was acquired by the City and prison facilities were built.
In 1996, an in-vessel pilot facility for composting food residuals opened on the island. (See “Correctional Complex Launches Into Food Residuals Composting,” July 1998.) Utilizing an IPS agitated bay technology with positive flow aeration controlled by a timer, the facility was designed to handle 10 tons/day of food residuals from on-site kitchens. The operation, under ORI’s management as well, currently processes approximately 25 tons/day of food residuals collected from prison kitchens by Department of Sanitation trucks. Wood chips from recycled wood and tree parts are used for bulking agent, combined with food residuals at an approximate ratio of 2:1, depending on the mass balance. Active material remains in bays for 15 to 20 days. The material is cured over an aerated floor, then moved to an outside location where it is turned once a week for two months, screened, and used on the island in gardens, the inmates’ farm, and in landscaping projects. Overs from the screening process are reused as bulking agent. The program captures more than 80 percent of Rikers Island food residuals. In 2004, 4,500 tons of food residuals were processed at the facility.
FINISHED PRODUCT AND PUBLIC EDUCATION
Compost produced at the City’s two yard trimmings processing facilities is used by the Parks Department for remediating soil and improving landscapes throughout all five boroughs of New York, distributed to residents at giveback events, delivered free of charge to hundreds of City community gardens and associations, and used by the Department of Transportation as well. Through more intensive composting, better curing, and improved screening technologies, end product quality has steadily improved from year to year.
The NYC Compost Project, BWPRR’s compost education and outreach program created in 1993, was also suspended in 2002 and 2003 due to budgetary concerns. The Project returned along with yard trimmings collection in 2004 and 2005. It serves as the distribution channel for compost, and also allows the BWPRR to gauge community interest and participation levels. Community feedback is of critical importance to Robert Lange and his staff, who have gone to great lengths to understand how the public responds to the department’s collection, education and outreach programs.
At giveback events for the finished product, which is available in unlimited, “load your own” quantities to each resident, there are also subsidized sales of home composting units, master composters on-hand to answer questions, and informational literature on composting, “leave it on the lawn” grasscycling, and how to use a worm bin. Information is available in English, Spanish, and Chinese. Events are held two to three times each spring and fall in all five boroughs at the City’s botanical gardens, in parks, schools, business parking lots, at the compost facilities, and even in such places as Shea Stadium.
Composting workshops for residents, master composter certification programs, “worm-shops” for City teachers, and landscaper training are conducted as part of the program as well, and held at the Staten Island, Brooklyn, Queens, and New York City Botanical Garden in the Bronx. “Paperless” information on composting and environmentally friendly urban gardening, as well as event schedules, can be found on the NYC Compost Project’s website, www.nyccompost.org.
CHALLENGES AND SUCCESSES
Residential participation rates with regard to yard trimmings collection, and the popularity of workshops, givebacks, and the public education campaigns, are encouraging to BWPRR staff. New Yorkers’ interest in recycling, composting and waste reduction programs often exceeds what can be expected of such a diverse, urban population. The combination of past organic diversion efforts, and current activities as reinstated after the suspension, have been tremendously effective. But in reality, yard trimmings represent a small percentage of New York City’s waste stream (approximately five to six percent in the autumn of 2004, the peak season for yard trimmings as reported by a recent waste characterization study). Diversion of other organics – namely food residuals and soiled paper, which collectively represent approximately 27 percent of the City’s waste stream based on preliminary findings of the same study – will be much more complicated to tap for diversion.
While the landscape organics portion of the City’s program has been a success, challenges exist here as well. Since 1997, three facilities on DOP land have been developed and used for composting, then taken back by Parks for other uses or vacated by composting operations due to other pressures. Considering only half a dozen or so of suitable DOP parcels have been identified – with three already taken back – the prospect for siting future composting operations remains uncertain. The Fresh Kills site may be available for long-term use, however both Soundview and the proposed Spring Creek facility may have limited life spans. “The City doesn’t have large tracts of land that can be set aside for the purpose of composting,” Lange says. Indeed, perhaps the City’s biggest challenge is finding, and keeping, appropriate sites for composting “in an environment that isn’t real estate rich.” Very few parcels exist that are larger than 15 acres and in areas not adjacent to communities.
Although setting out yard trimmings in plastic bags is a convenience for New Yorkers, and hasn’t impacted the quality of finished compost, Lange foresees going to paper within a year or so. In addition to being an aesthetic concern at the City’s composting facilities, debagging operations are very costly, and yard trimmings often go anaerobic in the plastic bags. Since paper bags are more expensive, BWPRR is considering buying them for residents for the first year transition, and requiring them to buy their own after that.
With regard to capturing a higher percentage of organics, specifically food residuals, the City is taking a hard look at mixed waste processing. In 1991, the City tested source separation and weekly collection of residential food residuals in Park Slope, Brooklyn, a district that has “historically embraced environmental initiatives.” Although participation rates were high, BWPRR found collection efficiency was too low and far too costly to do frequently enough (more than once/week) to avoid health code issues. Further, the act of segregating food proved to be unpopular with residents, and analysts surmised that if the program didn’t work in a community as progressive as Park Slope, it had little chance of success in other New York metropolitan areas. “Food waste collection has to be done in a way that doesn’t impose a burden on the public and can’t fundamentally change the way the department does collection, which is very efficient for a city environment,” points out Lange. “We believe [residential] source separation of food waste just isn’t going to work here. The only way we see it’s possible is through MSW composting.”
It’s important to note that BWPRR’s interest in MSW processing is not to replace existing source separation programs, but rather expand diversion through recovery of materials they feel are too costly or difficult to capture in any other way. Should an MSW facility be built and utilized, department plans are to keep and expand source separation programs as much as possible, and use mixed waste processing as a supplemental, not primary, means of achieving diversion goals.
In 1997, BWPRR conducted a pilot to gauge the potential effectiveness of recovering recyclables through mixed waste processing and evaluate the possibility of composting the organic portion. Since the pilot only looked at one day’s worth of mixed material, results from composting the organic fraction were too inconclusive. In 2001, a full-scale pilot was conducted by sending waste to Bedminster Bioconversion Corporation’s facility in Marlborough, Massachusetts. The study concluded almost 100 percent of the organic fraction of the waste stream could be captured, 70 percent of the entire waste stream could be recovered for recycling, and the program would require no additional public education nor represent an increased expense over existing disposal costs.
New York City has been exploring the possibility of building a composting facility on City-owned land adjacent to the Hunts Point Cooperative Market in the South Bronx. Hunts Point is the largest produce terminal market in the United States. It handles about 50 percent of all the produce sold in the New York metropolitan area, and generates approximately 11,450 tons of food residuals annually. BWPRR has been in discussions with the market for more than ten years, and would utilize the facility to compost organic residuals produced at the market as well as to conduct further pilot studies of MSW composting.
DSM Environmental Services, Inc., an environmental consulting firm located in Ascutney, Vermont, was hired by the New York City Economic Development Corporation (EDC) and BWPRR to conduct a feasibility study of organics recovery potential at Hunts Point, including material from the Fulton Fish Market, which moved to Hunts Point in July 2005. The Fish Market generates approximately 1,720 tons/year of food residuals. DSM conducted a waste characterization analysis of both markets, as well as assessed the potential of organics recovery systems suitable for processing waste. The firm also evaluated several parcels of land owned by the City at Hunts Point to assess the suitability of siting an organics recovery facility. Findings of the study have not been officially published and are currently under review.
New York City’s choice to pursue and develop MSW composting is contingent on a multitude of factors, but ultimately will be guided by a combination of political and economic forces. The City’s size, infrastructure, and socioeconomic conditions create a unique, challenging environment for implementation of diversion and recycling programs, and a multifaceted approach is critical to its success. The yard trimmings collection and composting strategies have embraced this comprehensive approach, operating efficiently, effectively, and bouncing right back after post 9/11 budget deficits shut the programs down. In spite of the many hurdles faced in the past, and numerous challenges looming in the future, Robert Lange and his staff have designed, implemented and maintained an excellent yard trimmings collection and composting program. A testament to their success is the remarkably high approval rating they get from the residents of New York City, who, to borrow a phrase from vaudeville, can really be a “tough crowd.”
WASTE CHARACTERIZATION STUDY
THE final phase of a four-season waste sort was completed in August 2005 as part of New York City’s latest Waste Characterization Study (WCS). A preliminary study, or “snapshot,” was done in the Spring of 2004, looking at waste (the sum of both refuse and recyclables as defined by the report) from the months of May and June of the same year.
Beginning with a sort in the Fall of 2004, the more comprehensive WCS divides waste generation percentages by housing density and income strata, and breaks waste down into more than 90 separate material categories, some of which are further segmented into subcategories. The study includes 17 categories for organics. The final report will include a full analysis comparing 2004/2005 findings to those of New York City’s 1989/1990 study. An article on the results of the WCS will appear in an upcoming issue of BioCycle.


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