May 17, 2011 | General

Composting Roundup

BioCycle May 2011, Vol. 52, No. 5, p. 12

San Francisco, California
Since the city of San Francisco launched a pilot program in 1996 to compost organics, residents and businesses have recycled more than 907,000 tons of food scraps and plant material by placing them in designated green bins. According to Recology, the company contracted to do the city’s garbage collection, recycling and composting, the CO2 emissions avoided by returning the produced compost to the soil rather than sending the organic materials to the landfill add up to the equivalent of removing all traffic that traverses the Bay Bridge for 777 days, or more than two years. Around 250,000 vehicles travel the bridge daily.
Organics recycling, mandatory in San Francisco for the past two years, produces 95,000 tons of finished compost annually, which is utilized by area farms, vineyards and residents. Recology states that methane reduction and carbon sequestration account for a combined CO2 emissions benefit of approximately 354,600 metric tons. “These new numbers further illustrate what residents and businesses who actively participate in the compost collection program intuitively understand, namely that placing food scraps and plants in green bins so that these materials are composted instead of going to a landfill is a highly effective way to help protect the environment,” says Mike Sangiacomo, Recology’s president and CEO.
The figures are based on protocol set by the Climate Action Reserve. “Offsetting the emissions from all vehicles crossing the Bay Bridge for more than two years is outstanding,” says Melanie Nutter, director of the San Francisco Department of the Environment. “These numbers show what you can accomplish with the flexibility of San Francisco’s regulatory structure and a remarkably dedicated service provider.”
Compost Quips
Perhaps best known for his membership in The Weavers folk music quartet, Lee Hayes was also an avid gardener and environmentalist. Shortly before his death in 1981, Hayes – who bequeathed his ashes to his own compost pile – penned the following poem, which former band mate Pete Seeger quickly set to music:
In Dead Earnest
If I should die before I wake
All my bone and sinew take
Put them in the compost pile
To decompose a little while
Sun, rain and worms will have their way
Reducing me to common clay
All that I am will feed the trees
And little fishes in the seas
When corn and radishes you munch
You may be having me for lunch
Then excrete me with a grin
Chortling, ‘There goes Lee again’
‘Twill be my happiest destiny
To die and live eternally
Edmonton, Alberta
Solid waste composting rules set limits on trace contaminants in the form of heavy metals in the finished compost product. A recent University of Alberta study was designed to assess the impact of various metal contaminants on compost quality. A critical step in the study was to estimate metal transfer during composting. This was achieved by measuring the corrosion rate of different contaminants during the high-rate composting stage for three weeks using alfalfa hay and straw as a composting substrate.
Losses and/or gains of various metal specimens were measured to estimate the amount of metal released into the compost. Of seven types of potential contaminants measured, stainless steel and brass screw and light bulb aluminum alloy thread contacts showed little weight change, suggesting low cause for concern in terms of potential metal release during composting. The highest metal release per unit area came from light bulb foot contacts, followed by galvanized steel nails and zinc-plated screws. The research was conducted by Shouhai Yu, Daryl McCartney, Weixing Chen and Lixian Zhou of the University of Alberta, and Salim Abboud of the Alberta Research Council. A full report on this research study – “Trace Metals In Municipal Solid Waste Compost: Sources and Research Methodology” – is being published in the Spring 2011 issue of Compost Science & Utilization, BioCycle’s sister publication (
Plano, Texas
“It’s so quiet you can stuff a T-shirt in there and use it as a pillow,” suggests actress Rachael Harris in a commercial touting the new quieter, fully compostable SunChips bag. Last year Frito-Lay rolled out a first wave of “100% Compostable” packaging amidst much self-induced fanfare, only to pull the plug and revert to conventional packaging on all but its original flavor multigrain snacks following an avalanche of customer complaints that the packaging was too loud (see “Chipmaker’s All-Or-Nothing Claim Sets The Bar In Big And Bold,” August 2010 and “SunChips Pulls Compostable Packaging,” October 2010). Now, as Harris effectively demonstrates to passers by during the commercial, the new fully compostable packaging has quieted down considerably, dampening the crinkle factor from a deafening 80 to 85 decibels to a tolerable 70 decibels, according to the Associated Press. The new bag was created by using an adhesive to bind a packaging layer protecting the contents of the bag to another carrying the outside logo and label. According to Frito-Lay packaging engineers, the rubber-like adhesive functions as a sound barrier.
A less-publicized controversy had to do with whether the SunChips bags are indeed compostable under backyard conditions. According to the SunChips’ website, Frito-Lay went to great pains to assure that they were. The website offers excellent information on the merits of composting as well as a tutorial on how to compost effectively. It explains that “the SunChips compostable bags will break down in about 14 weeks if the compost temperature is maintained at about ~130°F” and counsels “Before you start composting, make sure you have collected enough materials to fill your compost bin completely.” Unfortunately for Frito-Lay, that’s just not the way most home composters build their compost piles. “If the compost pile does not get that hot, it’s OK,” the website states. “The SunChips compostable bag will still break down, it will just take longer.”
Wilmington, Delaware
In May, Waste Management, Inc. (WM) announced it invested in Peninsula Compost Company (PCC), which owns and operates the Wilmington Organics Recycling Center (WORC). This announcement was followed a day or two later by another stating that WM is developing a source separated organics composting facility in Apopka, Florida. The company recently opened up an 8-acre organics recycling site next to an existing landfill in Okeechobee, Florida. (This activity in Florida coincided with WM’s lobbying campaign to repeal the state’s ban on landfill disposal of yard trimmings.)
The WORC facility, which utilizes an in-vessel Gore Cover System, currently processes between 300 and 400 tons/day of organic waste and is permitted for an average of 550 tons/day of throughput (see “Urban Facility Delivers Food Waste Composting Capacity,” June 2010). “WM’s investment in PPC will allow it to provide an organics solution to existing and potential customers,” says Charles Gifford, managing director and cofounder of The Peninsula Compost Group, LLC, one of WORC’s founding partners. Adds Tim Cesarek, managing director of Organic Growth at WM, “This facility happens to be in a great location, servicing the DelMarva Peninsula, the Philadelphia region and New Jersey. WM has hauling fleets in the region that are collecting organics and need a place to take them, as well as customers who are asking for organics collection service.”
The WORC facility could add more than 200,000 tons to its current annual organics processing capacity of more than 1.7 million tons, notes WM, adding that its involvement will accelerate expansion of PCC’s organics recycling services and development of value-added organic products in the mid-Atlantic states.
Atlanta, Georgia
A 16-year-old ban on landfilling yard trimmings was rescinded in Georgia April 14, as the state Senate followed the House in passing House Bill 274, which ultimately included language lifting the ban. Georgia Governor Nathan Deal has until May 24 to sign the bill into law and was expected to do so without a hitch, since the legislation is tied to the state’s $7 million Solid Waste Trust Fund. If the bill becomes law, yard trimmings will be allowed at 10 lined landfills in Georgia that have methane gas collection.
Opponents of the bill, including the U.S. Composting Council (USCC), had been working feverishly to strip the repeal language out of the bill – and replace it with language recognizing the benefits of composting as the highest and best use for yard trimmings – ever since the state House passed its version earlier in April. USCC lobbyist Jill Johnson had successfully worked with senators to win a 28-18 vote removing the repeal language. But the following day, the bill’s sponsor Rep. Randy Nix won a vote in the House disputing the Senate changes. Once again the Senate voted to keep the changes in place, which sent the bill to the conference committee made up of three state senators and three representatives. The committee added the original language back into the bill, which passed narrowly with 31 senate votes (at least 29 votes were required to win passage).
According to lobbyist Johnson, three critical factors played into the bill’s passage:
• Approval by the Georgia’s Environmental Protection Division (EPD) Director F. Allen Barnes, who testified he did not think the ban repeal would have significant impact on the compost and mulch industry.
• Inclusion of the Solid Waste Trust Fund renewal, which was tied to the passage of the state’s fiscal year budget.
• Late involvement by the composting trade group, thus missing multiple critical opportunities to be at the table with other players such as Waste Management, Republic Services, Inc., and the National Solid Wastes Management Association – bill proponents who began working with EPD to craft the language before the beginning of the legislative session.
According to proponents of HB 274, counties and municipalities are now free to decide for themselves how to manage their waste streams. Proponents also argued the additional tipping fees will help see the 10 landfills – half of which are public – through tough economic times. Georgia’s composters are bracing for their own tough times.
“It was a sad day for the environment and the composting industry in Georgia,” says Melia Lesko, cofounder and vice president of Greenco Environmental, LLC, a commercial composter in Barnesville. “Composters like Greenco Environmental depend on these yard trimmings to fuel their business and create jobs. The bill claims to promote renewable energy by capturing methane from landfills, yet woody trimmings like tree limbs take decades to decay and if prevented from being landfilled, could immediately be used in more productive ways. The impact will not be felt instantly, but there is already a lot of competition for carbon, and this will make things all the harder for us.”
Boca Raton, Florida
Industrial Composting: Environmental Engineering and Facilities Management by Eliot Epstein, PhD (CRC Press, 2011) examines key operational aspects and challenges associated with composting, with strong emphasis on odor mitigation, pathogens and aerosols. Designed for composting professionals and supported by extensive references, the book includes sections on facilities planning and design; odor management; material, energy and water balancing; economics of product marketing and sales; public relations, participation and communication; pathogen concentrations related to feedstocks, and; bioaerosols associated with composting and potential disease factors. Charts, photographs and tables help illustrate key concepts. This up-to-date volume was written to serve growing interest in the use of composting for biosolids, food waste and other specialty areas.

Sign up