Bringing compost to the curb

Interest in composting is rising across the U.S. as many cities and towns have started their own collection and education programs.

Residents in Wellesley, Massachusetts, had been dropping off food scraps for composting for six years before the city partnered with Massachusetts-based Black Earth Compost, a company specializing in handling organics collection, to offer curbside collection.

The town now offers drop-off and curbside collection programs, providing residents with more than one option for their organic material. Wellesley residents can drop off their material at the transfer station for free or can leave it at their curb once a week for pickup for a fee of $36 per month.

“Food waste still has value and use,” says James Manzolini, Wellesley recycling and disposal facility superintendent. “Why would you landfill something or throw something out that is still a benefit to society? If something has a second use or a second life, that just makes the most sense to capture that.”

Before starting the curbside compost collection program with Black Earth, the town sent a survey to residents participating in the drop-off program.

“When we put out a survey to the residents participating in our drop-off program, one of the biggest feedbacks we got is that it’s gross,” Manzolini says. “They don’t like putting the smelly bin in their car, dumping it and driving it home. This gives those residents the option of not having to do that.”

For the first 250 residents who signed up for Black Earth, the town supplied starter kits with bins and liners for both the drop-off program and Black Earth. This included a 13-gallon bin and liners. Wellesley paid for the starter kit for the first 250 residents who signed up for Black Earth, and Manzolini believes the town has distributed about 600 to 800 starter kits since the inception of the curbside program.

“We are familiar with the efforts of diverting food waste,” Manzolini says. “We know that there’s a few players in the area, we’ve got Cerro, Black Earth and City Compost. Black Earth is probably the largest and most passionate about [its] mission. They were kind of an easy choice. They rose to the top in experience, size and passion.”

Black Earth has helped Wellesley launch a few pilot programs at local schools. The town also has worked with Cero, a waste management service based in Boston, on school composting programs in the past.

“Now that the school programs are on their way, taking off, expanding and growing, I have a suspicion that Black Earth will probably be the town’s go-to,” Manzolini says. “We are still working with Cero at a few places, but Black Earth has developed a good reputation.”

Rapid expansion

Black Earth has dedicated its mission to responsibly collecting food scraps from residents, schools, restaurants and more. It provides service to customers across eastern Massachusetts, Rhode Island and New Hampshire.

The composting company grows its customer base by partnering with local towns, offering townwide contracts and private-pay subscriptions. Through these initiatives, Black Earth has signed on about 40,000 residential curbside customers and another 1,000 to 2,000 commercial customers, the company says.

Black Earth says it has no plans to slow down. The company currently serves Massachusetts and Rhode Island and is working on branching into New Hampshire.

In the next couple months, the company has eight towns lined up to launch.

“We collect upward of 4 to 6 tons per truck, and we collect upward of 700 houses and dozens of commercial stops in a route,” says Colin Rose, chief of collection operations for Black Earth.

Black Earth has 40 trucks for collecting compost curbside, with three more trucks on the way. The company has three compost sites and plans to build more in response to the growing need for capacity.

In July, Black Earth opened a facility in Manchester by the Sea, Massachusetts, using grants from the U.S. Department of Agriculture for organic fertilizer production. Like the company’s Groton facility, it’s an indoor composting facility, while its site in Framingham is an outdoor composting site. Black Earth stations trucks at all sites as well as satellite sites in Rhode Island and Wakefield, Massachusetts.

“The amount of growth I’ve seen in the company is a sign that [composting] is becoming more accepted and is growing as a cultural movement,” Black Earth Compost Site Foreman Syed Dong says.

The composting market is mainly word-of-mouth, and most of Black Earth’s advertising comes from elementary schools and parent-teacher organization (PTO) groups.

“Kids love it,” Rose says. “They compost at lunch, then they come home and want to compost too. The PTO groups will work a deal with us where we’ll donate compost for everyone that signs up or a portion goes to the schools through a referral code.”

Towns that offer townwide funded programs seem to be most successful, Rose says. Black Earth does charge for collection but offers density discounts, where the higher the number of people who sign up, the cheaper the collection will be.

“Since I’ve been with them, it seems like every week it becomes more accepted and more realized this is what we need to be doing to decrease greenhouse gases,” Rose says. “What makes us different from other composters is that we have our own sites. We collect it, we process it, then we get that soil back out.”

Rules of composting

As a commercial composting company, Black Earth collects items that aren’t traditionally accepted, such as bones, meats and shells. The company also accepts certified compostables in its mix, including plates, forks and knives.

Black Earth requires certification through Technischer Uberwachungsverein (TUV), a German standards organization, or Biodegradable Products Institute (BPI) in accordance with American Society for Testing and Materials standards for compostable products in North America to confirm the quality, standards and safety of a product. These certifications are given once thorough testing has been done to ensure product packaging does not have microplastics and will turn back into soil.

Black Earth Compost provides customers with a list of items that are accepted to ensure the soil given back to customers is contaminant-free. Food items such as coffee grounds, eggs, dairy, seafood, fruits, vegetables, grains, desserts and oils are acceptable. This includes the shells from eggs and seafood, fruit pits and skins, tea bags and coffee filters. Household items that Black Earth accepts include wood, cotton balls, wine corks, pet food, plants and leaves.

Each of the company’s sites has contracts with municipal haulers to take carbon sources, primarily leaves. To keep pesticides out of compost, grass is not accepted unless it’s from a certified organic partner.

Black Earth specifically lists on its site that paper, cardboard, plastic, metal, stickers and other specific household items are not compostable.

Compost and collection process

The process for starting up programs in new towns varies depending on how many residents sign up and how close together the houses are. Once enough people preregister, Black Earth plans a route for that area.

“The more people that sign up, the cheaper it’ll get,” Rose says. “Every few hundred, we’ll drop 10 percent on the price.”

To turn compost into soil, the trucks haul in the food waste to its facilities in Groton, Manchester by the Sea or Framingham. Food is mixed and dumped on a bed of carbon consisting of leaves.

The compost pile sits for about a week to dry and then is mixed up again with more carbon added. It sits and mixes one last time before getting fed through a trommel screen twice to take out sticks, rocks and plastics.

A Black Earth worker picks out fruit stickers and small contaminants that made it through in the final stages. Finally, the compost is sent off to be bagged and eventually makes it back to customers or local garden centers.

Contamination challenges

The main challenges composting companies face are counterfeits and contamination. Many products such as plates, cups, liners and utensils will be advertised as compostable and BPI- or TUV-certified but instead, the material is only biodegradable and not certified compostable.

“There is a problem in the market right now with counterfeit certified compostables,” Rose says. “It’s people who aren’t taking the extra step to check [who] contaminate compost piles. BPI and TUV allow people to search a brand and find out if it’s legitimately certified or if it’s a scam.”

Education on compost is lacking, leading to contamination, Dong says. Because compostable plastic dissolves within three weeks at Black Earth’s facilities, the company says it discovers and removes noncompostable plastics at that time.

“Our piles sit on site for about six months, so anything after three weeks we know it’s contamination,” Dong says. “We know at that stage stuff shouldn’t be in there and we pull it out by hand. It has been a consistent issue.”

The author was a summer intern with the Recycling Today Media Group. This article was edited Oct. 16 to correct Syed Dong's name, which originally was misreported as the unmarried surname of Muntaz rather than Mumtaz. We apologize for the error.