The world's largest garbage dump is a now a green oasis that powers Staten Island homes

The last steaming load of garbage arrived at Fresh Kills Landfill on March 22, 2001. Over the course of 53 years, it had become the world's largest landfill with no less than 150 million tons of municipal solid waste mounds rising 20 stories high, reports the New York Times. However, Staten Island residents were fed up with living next door to one of the world's great eyesores and rallied to turn the ecological nightmare into a sustainable park. Their dream nears completion now as Freshkills prepares to open its North Park in spring 2021.

Thanks to the nearly two-decades-long effort of the Freshkills Park Alliance and the City of New York, the landfill is being transformed into an "extraordinary 2200 acre urban park that will be a model for sustainable waterfront land reclamation." According to the non-profit's website, this transformation began when the Municipal Art Society collaborated with the City of New York to sponsor an international design competition won by landscape architecture firm Field Operations, who designed an illustrative park plan integrating "2,200 acres of open grasslands, waterways, and engineered structures into one cohesive and dynamic unit."

But how does one turn a gigantic steaming pile of garbage into a green oasis? By covering, stabilizing, and maintaining. The landfill was covered with different layers of soil, geotextiles, and a geomembrane to stabilize landfilled waste, separate the waste from the environment and park visitors, and prevent the release of landfill gas to the atmosphere.

"Along with the landfill cap, a collection of swales, down chutes, and retention ponds collect and manage stormwater to prevent erosion to the cap caused by rainwater," Freshkills Park states. "Directly on top of landfilled waste is at least two feet of soil known as the soil barrier layer. This layer covers the garbage and ensures the hills are stable."

This layer is followed by the gas venting layer—"a thick geotextile made to promote collection and absorption of gas in soil"—and an impermeable plastic liner that neither water nor gas can move through. Then comes a drainage layer (with a geotextile similar to the gas venting layer) and a barrier protection material that's made of at least two feet of sandy soil. "Lastly, at least six inches of clean planting soil is spread over the barrier protection material. The soil is seeded with a native plant mix, whose roots help stabilize the mounds and absorb water," states the website.

These six layers are collectively known as the landfill cap and prevent landfill gas—created as anaerobic bacteria feed on decomposing waste—from migrating into the atmosphere. A network of wells, pipes, and blowers below the cap collects the gas from the capped landfill mounds and sends it to an onsite purification plant.

The gas is refined into pipeline-grade natural gas through a series of physical and chemical reactions at the plant and the resulting purified natural gas is sold to National Grid, "which distributes the gas to Staten Island residents for cooking and heating fuel."

Even as the Freshkills Park prepares to welcome visitors to its North Park in spring 2021, most of the site remains closed to the public. "The park’s edges are opening first so that people can enjoy new parkland as soon as possible. Projects that provide direct connection to the communities surrounding the park have been given the highest priority," the park's website explained."

The rest of this remarkable piece of land will open by 2036 while serving as a "platform for generating knowledge applicable to a broad range of urban environmental issues", including the likes of reforestation, habitat restoration, soil production, water quality, alternative energy generation, and even attitudes toward park usage.