Mountains into mulch

Sevier Co. showing the world how to help solve garbage problem

Friday, June 15, 2018, Vol. 42, No. 24
By Linda Bryant

It’s no secret that the Great Smoky Mountains National Park and nearby tourist hubs of Gatlinburg, Sevierville and Pigeon Forge attract millions of visitors a year eager to catch a glimpse of black bear in Cades Cove, reach the top of Clingmans Dome or ride the Thunderhead at the Dollywood theme park.

The park itself is the most popular national park in the country, bringing in more than 11.3 million tourists in 2017, which is about five million ahead of the Grand Canyon, the second most visited national park.

But here’s a well-kept secret about the region you might not know: It’s home to what many consider to be one of the most innovative and effective solid waste processing plants in the world, Sevier Solid Waste Inc.

Not country – but world.

In fact, in some circles, the plant, often called SSWI, is downright famous, not only for the way it gets rid of garbage but for being able to successfully recycle and reuse so much of it.

“We’ve had people come here to see what we do from all over the world, and I mean everywhere – the Middle East, Russia and Europe,” says Tom Leonard, longtime general manager of SSWI. “They come to look at this process because it’s so unique. There are about a dozen or so facilities in the world, and we’re one of the oldest.”

The solid waste plant, located at 1855 Ridge Road in Pigeon Forge close to Dollywood, was one of the first places in the world to use rotating drums, or digesters, to break down its ever-growing waste stream into compost. The functionality of these digesters has been improved over the years through trial and error, and now they are considered models for composting plants around the world.

SSWI is currently putting the finishing touches on an expansion of the plant that features a new recycling facility adjacent to the composting operation, where materials that are not composted via the digester will be separated for recycling.

The new facility, Leonard adds, is expected to start operating this summer, is yet another step toward reducing waste at a place that’s already known for radically diminishing it.

“The new facility will help increase recycling and diversion rates, dramatically, I hope,” Leonard says. “It will make a big difference to be able to pull out plastic, aluminum and steel.”

How does it all work?

Unlike the vast majority of county’s solid waste facilities, most of the garbage that gets hauled to the Sevier County plant stays out of the landfill and is composted or recycled.

And it’s a lot of garbage – about 350 tons a day, which adds up to over 100,000 tons a year.

These massive amounts of waste are generated not only by residents of Sevier County, which includes the cities of Gatlinburg, Pigeon Forge, Sevierville and Pittman Center and over four dozen unincorporated communities but by tourists who swarm the area daily and commercial clients that come from as far away as Atlanta.

“Because of tourism, the amount is about double what a town of our size would normally be processing,” Leonard acknowledges.

The Sevier County program is also very different than the vast majority of recycling and composting programs in the world because residents and tourists don’t separate recyclables from daily waste prior to disposal as is done in most areas across the country.

Instead, Sevier County Solid Waste does all the picking apart of recyclables.

That means, for the most part, residents and tourists aren’t expected to divide their own garbage into separate categories such as glass, paper and plastic, which is the typical protocol for the majority of civic recycling programs in the country.

Workers hand sort the flow of garbage at Sevier County Waste Inc., removing any products like heavy blankets or jackets that could disrupt the recycling and composting processes.

-- Adam Taylor Gash | The Ledger

“Just about anything that’s organic can be broken down in our system, whether it’s paper, food waste or cardboard,” Leonard explains.

Biosolids from Sevier County’s wastewater treatment plant are also mixed in to the brew, and it will help contribute to the microorganisms eventually breaking down the waste into usable compost.

Sevier Solid Waste operates a Class I and a Class IV landfill.

The Class I landfill, used for household waste, is rarely used at SSWI because so much of that material is recycled back into compost at the plant.

A Class 1 landfill is the most environmentally harmful type, requiring heavy lining to prevent runoff, careful regulatory oversight and decades of maintenance. Garbage and waste that collects in these landfills is eventually covered up, but it never really goes away.

A Class IV landfill allows disposal of brush, construction and demolition waste and/or rubbish that are free of putrescible and household wastes.

“Typically, we are able to keep over 95 percent of the entire waste stream out of the Class I landfill,” Leonard says.

The current facility boasts a 70 percent recycling rate, the highest in the state, by separating electronics, mixed plastics, cardboard, tires and used oil for recycling and using the digesters to turn the remaining organic waste into compost.

That number is particularly notable when you compare it to national statistics. According to the most recent data from U.S. Environmental Protection Agency, the U.S. as a whole diverted about 34.6 of its waste in 2014.

Breaking the process down

To begin the process, massive amounts of waste – about 150 truckloads a day of mostly bagged garbage – are combined with some pre-processed compost and placed in 185-foot long and 14-foot wide rotating composting drums, called aerobic digesters. Heat and air are blown into the drums to kill pathogens and begin the composting process.

Waste churns in the constantly rotating drums for 72 hours. After this phase is over, much of the garbage resembles compost, but large pieces of plastic and metal that can’t be broken down into compost remain.

The remaining material is now chopped and sifted for glass and recyclables and then placed in windrows – narrow, long piles of material – inside of large covered buildings where it is further composted for roughly a month.

The end product is Grade A compost, which is suitable for use in landscaping, greenhouses or nurseries.

“We recycle over 60 percent of everything that goes through the plant, and it’s turned into compost that all goes out to market,” Leonard points out. “It goes to farmers, soil blenders, contractors, gardeners and anybody else that wants the material. “

SSWI also acts as a center in the Southeast for businesses and corporations who are seeking to get rid of their waste but want to act responsibly by keeping it out of the landfill.

“We are one of the hubs where you can take your materials to be composted,” Leonard says. “We are getting material from as far away as Atlanta, Georgia, and Greenville, South Carolina. It’s from companies like Wrigley’s and Mars that want to have zero waste. We get all kinds of stuff – Life Savers, chewing gum, pretzels, beans, ketchup.

Sevier Solid Waste turns garbage from Gatlinburg, Sevierville, Pigeon Forge Sevier County and the Great Smoky Mountains National Park into mulch using its ‘digester.’

-- Adam Taylor Gash | The Ledger

“They always have [waste] that they have to get rid of but they don’t want to take it to a landfill. They have to take it somewhere so that it will be recycled, so they take it here because we can compost it. Nobody else does that but us.”

‘Like a Star Wars movie set’

Nan K. Chase, a resident of Asheville, North Carolina, recently visited Sevier County to research its solid waste procedures and policies.

Chase, who calls herself a self-professed “municipal services geek”, says she’d like to see Asheville, which is also an area impacted by residential growth and tourism, consider innovative approaches similar to those used in Sevier County.

“I was so blown away by this waste plant,” Chase says. “It was very uplifting and like being on a Star Wars movie set. Everything is impressive and gargantuan, and there is a constant stream of garbage trucks and activity. I think it’s a real model for other cities.”

So why haven’t more municipalities or counties embraced using digesters?

One surefire reason is that setting up and operating a digester-centric solid waste operation isn’t cheap, and it’s not as easy to understand as a traditional recycling setup.

“Over the years we have upgraded and invested $25 million into the facility,” Leonard says.

Furthermore, Sevier Solid Waste uses a sophisticated process that requires a dedicated and knowledgeable staff. Voters who approve the funding for solid waste services simply might not want to give the green light to a process that, although it might save money in the long run, means having a large capital outlay at the forefront.

And then there’s the reality that many communities have their waste hauled off to landfills located outside their own jurisdictions, which can often lead to an “out of sight, out of mind” mentality.

Curiosity from Maury County

TDEC, the state agency that oversees and helps fund the Sevier Solid Waste plant, has high praise for the facility, but also says the approach is not always feasible for others.

“We applaud Sevier County’s commitment to innovation, and we encourage others to explore ways to better manage their waste streams and work toward a more sustainable future for Tennessee,” says Shari Meghreblian, commissioner of the Tennessee Department of Environment and Conservation. “Sevier County’s approach is unique and has certain benefits, but the approach would be difficult to emulate in other locations.

“We would recommend approaches that include source reduction, curbside recycling, hub-and-spoke recycling collection and marketing systems where multiple jurisdictions can work cooperatively to achieve economies of scale.”

At least one other region in Tennessee, Maury County, in the process of researching Sevier County’s digester approach to solid waste disposal and recycling.

The county was recently told by the TDEC that it needs to find a solution to a problem with its landfill at Chickasaw Trace Park, which is currently overflowing.

In May, Maury County Commissioners voted to close the landfill.

Current plans are to use another county-owned property to contain a collection center, transfer station and grinder and to ship waste that would have previously gone into the county landfill out of the county until clear decisions are made about a new landfill.

Some Maury County commissioners are considering developing a $25-30 million facility similar to Sevier Solid Waste’s recycling plant, although the issue hasn’t been proposed formally or voted on yet.

“This is an opportunity to bring our solid waste department into the 21st century,” Maury County Commissioner Donna Cook said at the commission’s June 6 meeting. “This is a wonderful thing that we could do for the taxpayers today and tomorrow.”