Technology, logistics make mass composting in Wisconsin challenging

Charlie Hildebrand and Riley Sumner
Wisconsin Watches

Until recently, the University of Wisconsin-Madison had a successful program to compost discarded food.

Beginning in 2009, the university collected food scraps in the campus cafeteria and sent it to the West Madison Agricultural Research Station for composting. In 2018, the university began taking the waste to the anaerobic biodigester, which is now owned by Clean Fuel Partners LLC. There, the waste is converted into methane for fuel.

But the company shifted focus, leading it to drop its UW-Madison partnership in 2021. Travis Blomberg, the campus resource coordinator for the UW–Madison Office of Sustainability, said the digester stopped feeding and now uses only feces as input. The change also undermined Madison’s city-wide attempt to compost food scraps.

The state Department of Natural Resources estimates that 1.2 million tons of material could be diverted from landfills to compost each year. About three-quarters of that is food waste, which produces methane, a harmful greenhouse gas, the DNR said.

Cities and universities are not alone in the fight to maintain mass food waste composting.

According to environmental nonprofit GreenBlue, only 7 percent of urban curbside composting programs in the nation’s 1,000 largest cities can accept food waste — just 3 percent of the U.S. population.

In contrast, 71% of Canada’s population has access to curbside programs to dispose of source-separated organics, including food scraps, according to the Ontario Foundation for Environmental Research and Education.

One waste management expert described it as Wisconsin’s “Catch-22.”

“We need people to move material, create enough business for facilities that want to compost, and then enough end markets for those facilities. And they all need to happen at the same time,” Casey Ramensky, DNR solid waste coordinator Lamensky) said. “And we’re too early, and if one of those options fails, there aren’t many backup solutions.”

Green Box Compost marketing manager Esai Ponce (left) and company founder and CEO Ben Stanger work at the company’s warehouse in Sun Prairie, Wisconsin, on May 25, 2022. About 100 residents and two restaurants subscribe to the Green Box Box Compost service to collect their organic waste. Subscribers can compost any food waste, including bread, meat, and dairy. (Cobain Dukehart/Wisconsin Watches)

cut off by contamination

The UW-Madison composting program experienced a series of setbacks, including contamination of its waste stream, before it was finally forced to close.

At the West Madison Agricultural Research Station, the facility’s system mixes and aerates organic waste in rows to produce compost. But Bloomberg said it has struggled with non-compostable materials — such as plastic bags, packaging and metals — in the university’s food stream.

The university has attempted to “clean up” its food waste, recruiting students to conduct waste audits in the campus cafeteria, and training staff to sort food waste and run it through a pulper.

Still, the waste created by the campus issue—paper containers and napkins slowed down the system, and lightweight objects were blown away. The farming station also had to perform expensive repairs on tractor tires punctured by metal silverware thrown into the compost bin.

Bloomberg said the contamination occurred in materials “on the front of the house,” namely food scraps thrown away by cafeteria customers. Contamination from non-compostable items is an “always problem” with food waste collection, he said, adding that “the scheme is not perfect.”

So when the opportunity came in 2018 to move the university’s composting program to an anaerobic digester — which uses a baler to separate food from contaminants — Bloomberg said the university signed on until the digester The operator of the appliance stopped accepting food scraps in July 2021.

“We can do everything we can, but we don’t have an industrial composter for this material near us (want),” Bloomberg said.

Food scraps are collected at the South Madison Farmers Market in Madison, Wisconsin, on June 14, 2022. The program accepts raw fruits, vegetables, coffee grounds, grains, rice, loose tea, eggshells and gourds. The scraps are sent to Neighborhood Food Solutions Farms in Fitchburg, Wisconsin, where they are composted. (Amena Saleh/Wisconsin Observer)

Municipal composting falters

Like UW-Madison, the city of Madison has led multiple food composting programs — all of which have proven ill-fated.

A recently canceled program in the city allowed residents to send food scraps to three different locations. The material is then sent to a biodigester that extracts methane from the waste. According to Bryan Johnson, the city’s recycling coordinator, the project ended after biodigesters began to specifically extract methane from cow manure — the same change that ended the UW-Madison project.

The city had previously tried two curbside composting programs that failed because they were too labor-intensive and food scraps were often contaminated. Coat hangers, towels, children’s toys and even deer heads are among the items causing the pollution, Johnson said.

But Madison is trying again to recycle food scraps. Thanks to funding from the U.S. Department of Agriculture, the city opened two drop-off sites for food scraps at farmers markets this summer, which will be sent to Neighborhood Food Solutions farm in Fitchburg for composting. The South Madison and Eastside Farmers’ Market sites will be open through October. 25.

While the operation is “super small,” Johnson said he hopes to expand the number of sites. So far, the two-site initiative has collected nearly 8,000 pounds of food scraps. It’s not much, but he says every ton of compost is a “win.”

In the long term, the city hopes to work with Dane County’s Sustainability Campus — a proposed landfill and waste disposal project at the Yahara Hills Golf Course — to accommodate a large-scale project.

“With all the pitfalls we’ve come along, it’s hard to be optimistic, but I’m still optimistic about it,” Johnson said. “I know we’re going to do it – it’s going to take a lot longer than I think anyone wants.”

Madison offers this guide to help residents decide what they can bring to the market’s food scrap sites. (Courtesy of the City of Madison)

Minnesota leads the way in composting

Minnesota has a number of municipal composting programs — including several that collect organic material by the curb. The Ramsay/Washington County Recycling and Energy Center in Minnesota plans to start curbside food scrap collection by the end of 2023. It is led by University of Wisconsin-Madison graduate Junalee Ly.

Residents will collect their food waste in thick compostable bags provided by both counties, dispose of it in the same way as regular trash or recycling bins, and then compost it at a waste disposal facility, Ly said.

“Our plan is unique because it relies on existing collection infrastructure and waste movers don’t have to change the way they deliver their services,” she said.

Lamensky, DNR solid waste coordinator, said food scrap collection programs are more common in large, densely populated cities, especially in coastal areas. In these limited land areas, landfills can be more expensive than composting.

A bright spot in Wisconsin: yard waste composting. The state’s yard waste landfill ban in the 1990s led to more than 200 municipal composting programs that turn an estimated 200,000 tons of leaves, grass clippings, and small brushes into compost each year, which is often given away for free. Ironically, That makes food waste composting a tougher business venture in the state.

“[Food waste compost]is often a more profitable product, but it’s hard to find a reason to buy (food scraps) compost – even if it’s a higher quality compost – when there is a pile of yard waste compost available for state is free,” she said.

The lack of infrastructure in Wisconsin has also caused municipal projects like Madison to start only to stall. Efforts to compost food again and again can confuse residents, increasing the chance of contaminating recycling waste streams, Ramensky said. Her advice: When in doubt, throw it away.

Subscription services dominate

While Madison has failed to maintain a city-wide composting program, there are private companies that turn food scraps into soil — and that comes at a cost.

The Madison area offers at least three services – curbside composting, Earth Stew and Green Box Compost. Green Box founder and CEO Ben Stanger started his company earlier this year to meet what he sees as a growing demand in the region. Green Box charges members a monthly fee of $24.

“I think there are a lot of young people who are generally sustainable (as a goal), but food and food waste is more specifically something they want to focus on,” Stanger said. “And I want to provide them with this in a way that’s convenient, simple and cheap.”

Lamensky said subscription-based services like Green Box continue to outpace the state’s municipal programs because private companies can “move more nimbly” and bypass the bureaucracy that could slow implementation.

She said the DNR is trying to help by providing Wisconsin municipalities with technical support and waiving reviews and standard license fees to encourage startup programs.

Some states and cities have state laws that encourage the diversion of food scraps from landfills. Minnesota’s statutory goal is to recycle 75 percent of waste by 2030. Wisconsin has no mandated benchmarks, but the DNR’s goal is to reduce food waste by 50 percent by 2030.

Despite the challenges, Ramensky hopes more cities will give it a try.

“As we have more examples in Wisconsin, I hope other cities will see it done effectively and be ready to follow suit,” she said.

Sustain Dane Intern Daphne Joyce Wu and Sustain Dane Development and Partnerships Manager Lucia Hunt collect food scraps at the South Madison Farmers Market on June 14, 2022 in Madison, Wisconsin. The program accepts raw fruits, vegetables, coffee grounds, grains, rice, loose tea, eggshells and gourds. The scraps are sent to Neighborhood Food Solutions Farms in Fitchburg, Wisconsin, where they are composted. (Amena Saleh/Wisconsin Observer)

Solve waste at source

The University of Wisconsin-Madison is looking at different options for bringing compost back to campus through a pilot project at the Agricultural Research Station. Unlike previous arrangements, Bloomberg said the material was limited to “behind the house” food scraps from the university’s four largest producers of food waste — accounting for more than half of all food waste on campus.

But the pilot program is only a temporary solution, and the university’s proposals to suppliers to find long-term composting facilities have so far been unsuccessful, Blomberg said.

The university is also looking at other ways to reduce food waste. For example, a team of students received funding for food waste reduction technologies through the Green Fund—a program that funds student-led projects to address environmental challenges on the UW-Madison campus.

The project places digital scanners in litter boxes to analyze food thrown away so the university can adjust its food purchases.

“This is a simple, straightforward, cost-effective solution that not only saves universities a lot of money, but also reduces the problem of some waste being made and going to landfill,” said Jacob Breit, a senior researcher who worked on the study. . project.

Blomberg agrees that reducing waste is the best and easiest solution.

“The bigger question,” he said, “is why do we generate so much food waste in the first place? It’s a valid question.”

Wisconsin Observer intern Erin Gretzinger contributed to this report. The non-profit Wisconsin Watch partnered with WPR, PBS Wisconsin, other news outlets and the UW-Madison School of Journalism and Mass Communication. All works created, published, published or disseminated by Wisconsin Watch do not necessarily reflect the views or opinions of the University of Wisconsin-Madison or any of its affiliates.

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