Long black tubes snake into a small mountain of rotting garbage, slowly sucking natural gas out of the gradually sinking pit.

Years ago, the west Georgia landfill would have leaked into the air tons of methane, a greenhouse gas that’s 20 times more damaging to the atmosphere than carbon dioxide. Yet with the help of an industrial partner, progressive city leaders have transformed this trash pit into a new revenue stream and a source of renewable energy.

Larger trash dumps around the nation are required by the Environmental Protection Agency to capture the methane gas that is given off as the trash decomposes. As the tubes plumbing the LaGrange landfill suggest, even the smallest community can voluntarily convert teeming trash heaps into a green — yet revenue-generating — venture.

The idea came about in 2001, when executives from carpet manufacturer Interface were searching for an alternative fuel source for the petroleum-intensive manufacturing processes used in making carpet. The company contacted LaGrange officials about converting the city’s bloated landfill into a clean, cheap way to conserve energy.

In Georgia, like other Southern states, cleaner alternative sources of energy can be scarce or expensive. Yet landfills, which dot big cities and rural towns alike, offer an often overlooked supply.

“Trying to get environmental and financial solutions are easy. Trying to get a social benefit is harder,” said David Gustashaw, Interface’s vice president of engineering.

After studying the idea for several years, LaGrange eventually decided to spend the $2 million needed to outfit the landfill with a processor and miles of pipeline. The project was completed last year and the city expects to turn a profit in just five years. Thanks to a 10-year contract with Interface and another nearby manufacturer that uses the gas, LaGrange has banked $300,000 in revenue from gas sales in the first year, said Patrick Bowie Jr., the city’s director of utilities.

Often, though, economics of a conversion don’t work for smaller sites, said Victoria Ludwig, program manager for EPA’s landfill methane outreach program.

The program counts some 400 projects designed to promote landfill gas as an alternative energy source, but only one-third of the projects are from sites, like the LaGrange landfill, that aren’t required by law to trap their excess methane.

It’s often no easy task. The LaGrange venture relied on an industrial partner with the gumption to spearhead a project and city leadership willing to shoulder immediate expenses for a financial windfall in the future. Also, it didn’t hurt that LaGrange had the necessary infrastructure in place to market the natural gas, which it has sold for years.

“It’s not subject to import taxes, it’s very reliable and it’s not coming from another country,” Ludwig said. “It’s right here in everybody’s backyard.”

From the garbage pits of LaGrange, methane is pumped down into a tangle of gears in a musky valley. The gas is chilled to remove water, then filtered into a long chain of pipes that runs through a dense patch of forest.

About nine miles away, the pipes lead into Interface’s factory, where the gas heats a massive boiler and reduces the amount of energy the company needs to buy each year by about one-fifth.

The landfill’s developers are now eager to help others to follow suit. They speak at colleges and companies about the venture. In June, they held a conference in LaGrange where more than 100 mayors and civic leaders from across the U.S. and South America learned about the project.

“We want to replicate this and realize this can be done on a small scale,” Gustashaw said.

“You think the way you always thought, you get what you always got.”

On the Net:

City of LaGrange: http://www.lagrange-ga.org/

Interface: http://www.interfaceinc.com/