BioCycle July 2009, Vol. 50, No. 7, p. 16
PURSUIT OF VERMICOMPOSTING
Western Michigan University (WMU) assessed four major composting methods for its food waste stream – windrow, in-vessel, vermicomposting and aerated static pile – utilizing a broad range of criteria established by campus operations and staff. Criteria included initial capital cost, operating cost, capacity of proposed site, energy requirements and greenhouse gas reduction potential, process speed, quality of finished product, and potential for research insights, along with teaching and learning opportunities. A 2008 audit estimated that food waste comprises about 30 to 40 percent of the solids in the wastewater that WMU sends to the Kalamazoo Wastewater Reclamation Plant through garbage disposals. The dining halls produce about 262 tons/year of food waste with an average of 4,500 students on the Dining Services meal plan. Vermicomposting came out the most favorably in the evaluation, garnering the most interest from possible community partners. “It promises new challenges for scaling up the technology and offers the greatest opportunities for developing a leading, carbon neutral approach to food waste management and integration with small-scale food production,” says the report.
Binghamton, New York
“TRAYFUL DINING” EXPERIENCE
Many college campuses are going trayless in their dining halls to reduce the amount of food wasted, as well as food waste. The State University of New York (SUNY) in Binghamton, however, is sticking with trays in its dining halls. “The meals are a la carte, so students need to pay for what they take, but we are offering what we call a ‘trayful dining experience,'” explains Juliet Burling, Environmental Resource Manager in the Physical Facilities Department. “We took the trash cans out of the dining halls so students return their trays with everything on them to the plate return area. Kitchen staff sorts the contents on the tray into recyclables, trash and compostables. The food waste is put through a pulper. Sodexo, the food service contractor, saves on labor by not having to take as much trash out each day. In the 2008-2009 school year, about 3,200 to 3,500 lbs/day of food waste and soiled paper were diverted to composting.”
When campus composting first started six years ago, the pulped food waste was taken to a farm on campus and composted. But as the volume increased, a nearby farmer was approached about taking it. He does the composting, and delivers finished material back to campus to be used on the grounds. SUNY Binghamton has 16,000 students, with six dining halls and five retail areas. Source separation is being rolled out to all locations. “Sodexo pays 40 percent of the trash bill, so they have a big incentive to recycle and compost,” adds Burling. “The program is primarily student-run. Between recycling and composting, we are at 40 percent diversion and the students plan to go higher.”
COMPOSTABLE GOODS ON-LINE STORE
Compostable Goods, an online store based in Williston, only sells products that can return to the earth. The products are all certified as compostable, identified as biodegradable by the manufacturer, or made of biodegradable materials. With over 300 products from 50 manufacturers, they aren’t limited to the usual commercial food service items like cutlery, plates and cups but include toys, clothing, household and garden goods, pet products, music and sports items, and yarn. Dr. Lynn Zanardi Blevins, a medical epidemiologist, officially launched the website, www.CompostableGoods.com, in October 2008. But she first got the idea in December 2002 after hearing William McDonough, co-author of the book Cradle to Cradle, Remaking the Way We Make Things, speak at a conference. The cradle-to-cradle principle advocates continuously reusing or recycling products and materials that are no longer useful in their original functions, so that they never go to a landfill. “It really made sense to me,” she says. “I wanted to offer products that break down completely at the end of their useful life, without releasing synthetic chemicals or toxins into the environment. Our products are still useful and valuable at the end of their life as precursors to compost, which supports soil and plant health.”
Finding products is actually harder than one might think, adds Blevins. “Some bioplastic items such as compost crock liners are easy because they are certified as compostable. Most other products not made from bioplastics are not certified as compostable, so I investigate to see if they are biodegradable. Manufacturers don’t list all the ingredients and materials on other products for proprietary reasons, so I have to make a judgment.”
She also considers how the product is packaged. “Ideally, all the packaging for our products would be biodegradable or at least from recycled content and recyclable, but that’s not the real world,” she explains. Blevins requests minimal packaging from manufacturers when ordering products and ships smaller products in Globe Guard® boxes made of 100 percent postconsumer waste recycled fiber.
PUBLIC RESPONSE TO WASTEWATER REUSE
Changing water quality regulations on the Willamette River are causing the city of Corvallis to consider water reuse as an alternative to discharging treated wastewater into the river. To assist Corvallis with understanding public attitudes toward reclaimed water – and then use the information to design an effective public involvement process – Karen DuBose, a graduate student in the Water Resources Program at the University of Oregon, surveyed households in the city. The survey was designed to assess the public’s level of knowledge and acceptance of reclaimed water. “Survey respondents were generally more accepting of uses in which they could expect a low degree of contact with the water, and less accepting of high contact uses,” she reports. “Gender, age, education, awareness of water quality problems, respondents’ personal sustainability ethic, presence of children in the household and trust in the utility to serve public interest were found to influence respondents’ acceptance of various uses of reclaimed water.”
DuBose also interviewed other wastewater reuse programs to identify successful methods of public involvement. She found that the most successful programs involved the public early in the process. “Providing access to the decision making process is critical to the success of a public involvement program,” she says. “Information should be provided to the public in as many forms as possible. Corvallis respondents prefer to receive information from a variety of sources, including scientists and government officials. Only 21 percent of respondents chose public meetings as a good way to communicate with them.”
FEASIBILITY OF CODIGESTION
Vermont Technical College could be the home for a community digester that would process about 15 tons/day each of food waste and dairy manure. The college, along with Central Vermont Solid Waste District (CVSWD), Vermont Environmental Consortium and Vermont Sustainable Jobs Fund are using a $492,000 U.S. Department of Energy grant to study the feasibility of a digester on campus. CVSWD has a zero waste goal (see “Zero Waste Plan For Vermont Solid Waste District,” October 2007), and the digester would play a role in achieving it, note the project developers. Total cost of the feasibility study is $606,000. Manure would come from the college’s herd and neighboring farms. Food scraps would come from CVSWD’s current organics collection program. Results of the feasibility study are expected in September.
Vancouver, British Columbia
QUANTIFYING ENVIRONMENTAL BENEFITS OF 80 PERCENT DIVERSION
A study commissioned by Belkorp Environmental Services and conducted by Dr. Jeffrey Morris of Sound Resource Management Group, evaluated environmental benefits gained by reaching 80 percent waste diversion over a 20-year time span in the Greater Vancouver region. The 2008 diversion rate was 53 percent. Achieving 80 percent by 2029 would more than double avoided greenhouse gas emissions from 1.9 million metric tons CO2e in 2008 to 4.3 million metric tons CO2e in 2029, reports Morris. The incremental increase of 2.4 million metric tons of avoided CO2e emissions is equivalent to preventing emissions from over 600,000 private vehicles in Metro Vancouver in one year, or reducing current annual GHG emissions from cars in the region by nearly 45 percent. “Dr. Morris’ conclusions point to the need for a Zero Waste strategy that prioritizes diversion of all organic waste to composting systems, maximizes the effectiveness of existing recycling programs and initiatives, and accelerates the development of new diversion efforts such as Extended Producer Responsibility,” says Ted Rattray, president of Belkorp Environmental Services, which is involved in both recycling and waste disposal in the Greater Vancouver area.
The study also evaluated disposal options – landfilling and incineration – that would need to be employed as an interim solution to bridge the gap between the present and the Zero Waste objective. “Disposal options need to be assessed in terms of their flexibility and whether they will facilitate or hinder the achievement of zero waste,” says Morris. “Under these conditions, we found that disposing of MSW in landfills better meets this objective compared to incineration in three key environmental impact areas – climate change, human health and ecosystem toxicity.” To download the report, visit www.belkorp.com.
San Francisco, California
VIDEO SERIES ON CODIGESTION OF FOOD WASTE
The U.S. Environmental Protection Agency Region 9, in conjunction with the East Bay Municipal Utilities District in Oakland, California, are collaborating to reach out to municipalities and wastewater treatment plants to encourage them to accept food waste for anaerobic digestion. The outreach strategy includes videos on codigestion at wastewater treatment plants and an economic analysis. EPA Region 9 funded a pilot study at EBMUD to receive and process food waste to codigest with biosolids (see “Green Energy From Food Wastes At Wastewater Treatment Plant,” BioCycle January 2008). The pilot was a success and EPA is creating a short series of videos targeted toward the general public, local governments and treatment plants. A short, 2-minute video, available this summer, is fairly general and designed to educate the public about anaerobically digesting food scraps. A 6 to 7 minute video with more detail is also being created and is targeted to the general public, local governments and wastewater treatment plants. That will be available later this year.
Additionally, EPA is working on an economic analysis tool to help local governments and/or wastewater treatment plants determine the cost of implementing a codigestion project. This interactive tool will enable stakeholders to choose their scenario based on the type of area they live in and existing infrastructure (including existing food collection, etc). The tool will provide payback time and other relevant financial information, along with greenhouse gas emissions reduction information associated with the project. For more information, contact Laura Moreno at EPA Region 9 (email@example.com).
July 21, 2009 | General
BioCycle July 2009, Vol. 50, No. 7, p. 16