An Earth-friendly Waste Disposal Model

Imagine inviting a friend to visit for the weekend: you go out for a meal or two, buy extra groceries and do some cooking, go out sightseeing and shopping. There’s sure to be more than the usual amount of garbage and recycling put into the waste stream by the time you wave goodbye.

Now multiply that visit by, say, 14 million or so and you’re talking some serious trash.

That’s the situation for the communities near Gatlinburg, Tennessee, a compact city with a year-round population of just over 3,700. Thanks to the attractions of Gatlinburg itself, plus those of neighboring Great Smoky Mountains National Park, nearby Dollywood theme park and rootin’ tootin’ Pigeon Forge, those operations together host more than 14 million visitors a year. Sevier County, where all those tourist magnets are located, has a full-time population just shy of 100,000. (Dollywood alone hosts 3 million guests a year, while Gatlinburg and the national park both report more than 14 million annually.)

Instead of being buried under mountains of food scraps, take-out boxes and wrappers, cardboard, plastic straws and more, the communities in Sevier County use an unusual waste disposal system that “cooks” all the organic waste materials in massive digesters to produce a high grade composted soil, and then goes further in recycling almost all of what’s left. That clean “new” soil, in turn, goes to homeowners, landscape gardeners and others who pay little or nothing for the product.

Sevier Solid Waste, Inc. (SSWI), a nonprofit organization funded by a municipal partnership, has been a pioneer in the composting digester model for more than 30 years, and currently holds the title of largest mixed solid waste compost facility in the United States, according to Tom Leonard, the general manager there since 1999. By one count there may be fewer than 20 such digester systems worldwide, and only a few in this country.

“The main thing that SSWI does for the quality of life is keeping materials out of the landfill,” Leonard says. The process “composts 60 percent of everything that comes into the facility. In addition to composting we also recycle cardboard, tires, and have drop-offs for plastics, aluminum and paper products.

“This helps us to reach a total recycling goal of 72 percent per year. We currently have the best recycling rate of any county in the state of Tennessee, and we operate the largest mixed municipal solid waste compost facility in the country.”

That’s no small boast: SSWI handles 210,000 tons of material a year, including composting, recycling and landfill. In addition to serving the local municipalities and parks, SSWI takes in organic waste from companies all over the Southeast that want to boost their environmental credentials. “Right now we are taking M&Ms, coffee, pretzels, mints, pudding, butter, etc.”

The first steps toward success

In the history of SSWI, necessity was the mother of invention, or at least of implementation. Back in the late 1980s the city of Gatlinburg operated the landfill operation that took in all the trash from around Sevier County. But as that landfill reached its capacity—and after much discussion and anguish—the partner cities of Pigeon Forge and Sevierville decided to work together with Gatlinburg to find a better way. No one really wanted another conventional landfill operation, and a trash incinerator so close to the majestic Great Smoky Mountain National Park was out of the question.

That’s when someone discovered something called a drum digester operated by the remote town of Pinetop, Arizona. The system seemed like a good fit for Sevier County, and lo, it was built, at first operated by a for-profit company.

The size of the then-new Sevier digesters is hard to comprehend: each of the five digesters is 185 feet long and at least 12 feet in diameter. A never-ending stream of dump trucks pulls up to SSWI and feeds the digesters tons of organic waste from normal garbage hauling operations, which is mixed with sewer sludge and starter microorganisms to keep the digestive system running.

Inside the digester drums, which slowly rotate 24 hours a day, seven days a week, protrusions like long fingers help to break down the contents into smaller and smaller bits. After three days in the digesters, the resulting stream of “glop,” for lack of a better term, gets dumped into troughs where workers keep it moving along a conveyor system and remove large pieces of inorganic materials; those eventually end up in the landfill portion of SSWI. Yard waste and construction debris is handled elsewhere on site.

The odor at the end of the digesters is strong: a sweet-sour mix with a high “pee-ew” factor, just like overcooked garbage would smell. That odor, though, is localized close to the digesters; elsewhere at the facility, yard waste and branches filter the exhaust air to keep the countryside fresh. The noise level inside is: Wow!

Next, the broken-down organic material from the digesters runs through sifters with quarter-inch mesh to further remove unwanted inorganic pieces that may remain. Then the resulting composted material gets formed into long windrows—high berms under roof—to age for 28 days.

Then, voila! Composted soil.

“I just visited the newest facility in Oakland, California, and they are processing about 100 tons per day less than we are,” Leonard said, “but they have a plan to add two more digesters, and when that happens they will be the largest at 700 tons per day. We are currently processing 400 tons per day.

“We are still working on processing all the materials out of the back of the plant. We are getting ready to install some new equipment to help us to get all aluminum, tin, and No. 1 plastics out of our waste stream.”

Leonard is matter of fact about how well SSWI serves the unusual needs of a small community with huge tourist traffic and the restaurants and lodging establishments that accommodate them all. He recently returned from a composting conference in California.“Everyone out there talks about getting food waste out of the landfill and into the compost facilities, and this is something that we in Sevier County have been doing for 30 years.”

Focus on the Future

Such a successful long-term endeavor was no accident. The municipalities involved work in close partnership to foster ways they can all keep energy needs to a minimum, and they share best practices with visitors to the region. Recycling is made easy and organized, thanks in part to guidelines posted on the SSWI website.

Beyond that, SSWI serves as an incubator of sorts for future environmental leaders. One of these was Olivia Whatley, a Community Action Committee AmeriCorps service member who worked at SSWI during 2021/2022. Her duties included leading tours of the facility and other outreach: teaching classes about sustainability, operating social media, participating in litter and river clean-ups, and maintaining the recycling drop-off areas of Sevier County. She also wrote the SSWI annual report, planted trees, and worked with the Tennessee Composting Council.

“My time with SSWI taught me a lot about sustainability and soil science,” Whatley said. “My experience with them inspired me to learn more about sustainable farming and soil health. Mostly, it taught me just how possible and feasible large-scale sustainability is. I learned a lot about how nonprofits operate. The nonprofit experience that I gained has been the most helpful thing so far in my career.

“My job with SSWI was also my first full-time job, and along with the guidance from AmeriCorps, it was a great way for me to enter the workforce. SSWI is a special and important place that Sevier County is lucky to have.”

Today Whatley lives in New York City, where she is working on a Masters of Science from Johns Hopkins University and working part-time for a food-and-environmental justice nonprofit organization. Her future degree in Environmental Science and Policy will launch her into a career that helps mitigate human impacts on the natural world.

For Whatley, Leonard, and all the others who have worked at Sevier Solid Waste, Inc., every day is Earth Day.