A gas gauge in a meadow in FreshKills park. Photo: Nick Kimbrell
Can a landfill site ever return to nature?
6th July, 2010
One of the biggest landfill sites in the US is in the process of becoming a nature reserve and a recreation ground. Is this just papering over the cracks, or can our rubbish heaps really turn into something beautiful?
At its peak in the mid-1980s, the Fresh Kills landfill site received 29,000 tons of rubbish every day. Now much of the site, tucked on the western shore of New York City’s Staten Island, could be mistaken for a coastal nature preserve. Wildflowers grow on the sides of grass-covered mounds, which not long ago were mountains of rotting garbage, and there have been sightings of white-tailed deer and red-tailed hawks. For over a year, bi-monthly bird-watching tours have been popular with local enthusiasts.
The ongoing transformation of what was once the world’s largest landfill into what many hope will become New York’s most versatile park is emblematic of worldwide efforts to transform landfills and other contaminated sites into parks and public open space. But the ambitious Fresh Kills project, underway now for almost a decade, has also raised new questions about the potential profitability of these sites and the extent to which they can actually be restored.
At 2,200 acres, Fresh Kills – the completed park is to be restyled 'Freshkills' – will be New York City’s second largest park, about three times the size of Central Park. Located on the city’s least populous borough, Staten Island, the site was originally coastal marshland and estuarine creeks, but it opened as a landfill in 1948 to receive New York’s ever-growing supply of municipal solid waste.
According to the original plan the landfill was meant to be a temporary site, open for about three years as a dump and a land reclamation project. Nearly 50 years and 150 million tons of garbage later, Fresh Kills was the city’s only landfill.
Long the bane of Staten Island, the landfill was officially closed in March 2001, only to be reopened after the September 11 attacks to accept debris from the World Trade Center and serve as home to an FBI-led crime scene investigation.
Becoming something positive
The plan to turn Fresh Kills into a park was drawn up by the local and state governments with the support of the Municipal Arts Society. This plan, much of which has yet to be enacted, set out to include key aspects of urban ecology: to rehabilitate the land, promote sustainability and engage the local community.
'There definitely are environmental benefits to transforming the site into something positive, returning it to productive use,' said Carrie Grassi, Land Use Review and Outreach Manager at Fresh Kills, during a Jeep-tour of the sprawling site. 'But there is a psychological and social aspect to it that is about righting this wrong for the people of Staten Island and turning what was a landfill into a real asset, turning it into a public park, turning it into the park of the twenty-first century.'
Accomplishing this task, however, will continue to take a great deal of time and treasure. Before the bike paths and bridle trails, the barge gardens and kayak launches, much of the infrastructure to cap the landfill and capture the byproducts of the buried waste must be completed.
Of Fresh Kills’ four massive mounds, only the North and South Mounds have been capped. The East Mound, where dozens of trucks deliver bed-loads of dirt daily, will be covered by the end of next year. And the West Mound, where the 9/11 recovery took place, is expected to be completed by 2016.
This extensive capping process involves putting down a layer of barrier soil, a venting layer, a plastic geo-membrane, a drainage layer, two feet of barrier protection material, planting soil, erosion mats and, finally, plants.
According to Ted Nabavi, New York City’s director of Waste Management Engineering, the estimated cost for the 285-acre East Mound is around $250 million.
The site’s infrastructure also includes systems to capture leachate, a liquid byproduct of garbage, and landfill gas, composed principally of the greenhouse gases methane and carbon dioxide. The landfill, Nabavi said, can produce up to 10 million cubic standard feet of gas and 800,000 gallons of leachate per day.
Making use of waste
Although the site was retrofitted in the 1990s, Nabavi said that extensive monitoring systems were in place to ensure that neither of the potential hazardous byproducts migrates. These systems include 220 ground water monitoring wells, 12 surface waters stations, along with 200 gas wells, instruments and probes.
But the landfill’s byproducts are not just an environmental threat, they are a serious source of income. Leachate, which is separated into solids and liquids, cleaned and then sent to other landfills and into adjacent Arthur Kills River, is of little value. But landfill gas, about 50 percent of which is methane, brings in as much as $12 million per year after being upgraded to mains-gas quality at an on-site facility. Each mound at Fresh Kills can generate sizable amounts of methane for around three decades after being capped.
Other landfills, like Los Angeles’ Puente Hills, which is now the nation’s largest, use similar landfill gas collection systems. The Puente Hills Landfill captures the equivalent of 1,000 gallons of diesel fuel per day. But many landfills do not have this capacity, and are looking to acquire it.
'A lot of the interest that we get internationally is because we are making money from the gas. The city is getting money from the gas,' Grassi said, adding: 'We try to use that as a hook in, to get them to start thinking about the full life-cycle, about the site and other ways the site can be productive.'
The money from the landfill gas is a great benefit, but the real draw for the city and its residents is the prospect of thousands of rehabilitated acres of park in a city with limited opportunities to acquire new green space.
Dr Steven Handel a professor of Ecology at Rutgers University, who spent years researching at Fresh Kills and still advises the city of New York, marveled at the nascent transformation of the landfill.
'There’s no sense that I’m standing on over 100 feet of household garbage. There’s no odour and there’s no feeling that you’re on anything except rolling meadow in New York,' he said.
But the site’s rebirth does not mean that historic habit can or will be restored.
'We feel we can bring back many native species and many ecological services but a return to its historic state is not possible,' Dr Handel said, noting that the now-filled site had once been coastal marches.
Rather than a return to marshes, he said, the plan calls for 'wildflower meadows, coastal woodlands and shrublands,' which are native to, but increasingly threatened on, the east coast.
'It’s been done elsewhere, and I’m confident New York City can do it as well,' Dr Handel said, pointing to the success of similar efforts such as Liverpool’s Stadt Moers Park in the UK.
A work in progress
The idea behind reclaiming Fresh Kills is not new. Indeed, in recent years, efforts to turn closed and active landfills into parks and public open space have spread across the globe, from a sprawling site in Hiriya, Israel to Hong Kong’s Sai Tso Wan Recreation Ground, which showcases solar panels and wind turbines.
And despite fears that some landfill metals, like aluminum, will one day be valuable enough to mine, Nabavi and Handel each rejected that possibility for sites like Fresh Kills, which offer significant social and environmental benefits.
Portions of Fresh Kills already show extensive rehabilitation. Waist-high grass, native perennials and a growing number of trees dot the North and South Mounds. In the centre of Fresh Kills, at the junction of its creek system, there’s a family of nesting ospreys.
But the transformation into parkland is still very much a work in progress. Ongoing construction and more permanent reminders of the site’s past belie the pastoral scene. There is the string of trucks and earth-movers on the East Mound, the faint smell of landfill gas on top of North Mound, the several flare stations and occasional huts and gas gauges.
The good and the bad
Dr Lynne Westphal, a project leader and research social scientist for the US Forest Service, has worked extensively with hazardous, polluted and contaminated industrial sites. She noted that the extent of rehabilitation at such sites, known as brownfields, depends on the site and its unique variations. Depending on the nature of the site, she said, these variations may mean that all or only some areas get rehabilitated.
'Fresh Kills is a really good example,' she said. 'There’s a lot of variation within Fresh Kills…there are big mounds with garbage but there are undisturbed areas as well.
'If there are sufficient resources you can do a whole lot to return structure and function and ecological processes,' Westphal added. 'One of the coolest examples is Crissy Field.'
This 100-acre former airfield in San Francisco was heavily contaminated after the military left the site but, thanks to donors and thousands of volunteers, it was largely restored to its historic tidal marsh and dune habitat. Now Crissy Field is exactly what Freshkills’ planners hope their site will one day become: a dynamic and popular public park.
Perhaps less like Crissy, the work at Fresh Kills, where the historic ecosystems have been permanently changed, appears to be less about restoring than what scientists and city planners have referred to as the 're-naturing' and 'healing' of severely damaged lands. But even those working to transform the landfill have no illusions about this process being a cure-all for the growing problem of waste.
'This park project is really worthwhile. [But] we haven’t solved the garbage problem. And it’s not meant to sort of pretend that we have,' Grassi said. 'From our perspective, building a park is not meant to cover up what this site was, but we want people to really think about land and our impact, how we use it and how we think about it. A lot of the education work with kids that we do is about: "Where does your trash go? How do you think about reducing that?"'
Nick Kimbrell is a freelance journalist based in New York
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