“Death of Composting” read the title of a blog posted in June by Ayr Muir, founder and CEO of Clover Food Lab, a restaurant group in Boston, Massachusetts. Startling, to say the least, and certainly compelling to read.
Muir’s blog described how Clover Food Lab, a Boston restaurant company, moved to 100 percent compostable products in 2010: “I’d spent 18 months trying to get to that point. The last hang-up was the compostable lids. I’d finally gotten a new packaging company to develop a compostable hot lid and we were able to move to 100% compostable packaging.”
Muir posted the blog after learning that Save That Stuff, Clover Food Lab’s organics collection service, had not been taking Clover’s separated organics to a composting facility — in this case the WeCare mixed solid waste composting site in Marlborough, Massachusetts — because the plant had closed temporarily due to odors. Instead, those organics were being taken to a landfill. Save That Stuff had included Clover Food Lab on its “dirty route,” which was utilizing the WeCare’s mixed waste composting site, due to possible contamination in the material from noncompostable packaging.
Adam Mitchell, cofounder and CEO of Save That Stuff (STS) responded with his own blog, and a cheerier title — “Life Of Compost.” He explained why material collected from Clover Food Lab did not go to WeCare, and noted that STS is shifting away from front-of-the-house collection (postconsumer) and instead, will collect “food-only” from back-of-house. “In our industry, we find it increasingly challenging to find a processing outlet for the compostable dishware, utensils, and one-time use compostable cups,” wrote Mitchell. “The consumer market for these items advanced far faster than the end-of-life processing outlets. Farm-based composters have a limited tolerance for the compostable dishware, preferring food scraps.”
Toward the end of the blog, Mitchell noted: “At the end of this summer, a new Organics Processing Center will open at our facility in Charlestown (MA). We will accept Food-Only at this organics center. We will no longer be able to process compostable dishware/single-use service ware for composting — the items will be screened out.”
This situation in Boston brings to the forefront the opportunities and challenges with establishing collection programs to divert source separated postconsumer food scraps and Biodegradable Products Institute (BPI)-certified compostable service ware to composting facilities. The opportunities include capture of more source separated organics (SSO) that otherwise would go to the landfill or incinerator, enabling communities to achieve zero waste goals, and reducing methane emissions from disposal. The challenges include the potential for contamination from noncompostable “look alike” service ware, and concern on the part of composting facility operators that the certified bioplastics will not compost in their process.
While there is merit to those challenges, the reality is that many programs are successfully capturing and composting postconsumer food scraps that often include compostable products. Outreach and education, training and retraining, signage and visual prompts and instant feedback when contamination is found are core components. For those including compostable products, best management practices include establishing protocols to ensure they are BPI-certified (BPI is the North American certifier), minimizing exposure to “look alikes,” testing the compostability of the products at the composting facility and creating infrastructure (e.g., equipment, composting methods) to facilitate complete biodegradation.
AgRecycle, an organics collection and composting company in Pittsburgh, Pennsylvania, has been processing postconsumer food scraps and compostable products for at least a decade. Carla Castagnero, president of AgRecycle, had this reaction upon reading the blogs: “We do not have magic beans at AgRecycle. Yet, we somehow manage to get these products to compost and break down per their mission. Why does this myth persist that products don’t break down? I hear this from composters who have never even tried to work with these materials. I feel that the only legitimate concern voiced was that you do get an increase in noncompostables when accepting front of house organics, but that only happens from the untrained public or when there is employee turnover.”
Castagnero emphasizes the critical importance of having the equipment necessary to properly compost compostable products. In an interview with BioCycle in 2014, she explained AgRecycle’s protocol: “The first essential element is doing a pregrind. A composter would never throw a log in a windrow. Certain streams are organic and acceptable but they just need preprocessing. It is that simple for compostable products. …. Most of the compostable products we receive come in from small restaurants that also include their corrugated in with the food scraps. Typically these restaurants don’t generate enough corrugated to warrant a separate collection as a recyclable. The second reason is that I can’t stand litter. And the compostable cups will blow out of the windrow if they aren’t preground.”
AgRecycle uses a Roto-Mix mixer, size-reducing the material to around 2 inches. The company avoids putting anything over 4 inches in thickness in the Roto-Mixer. “The food scraps, compostable products and the corrugated are the only materials on our site that see the mixer,” notes Castagnero. “We have a grinder for yard trimmings. And typical grinders don’t handle corrugated well — it just flies through as a sheet. … Finally, the key to achieving biodegradation within the timeframe of a facility’s composting process is making sure piles reach and maintain thermophillic temperatures as required and getting the microbial population where it needs to be.”