The City of Philadelphia has agreed to pay $8.4 million toward the federal government’s cleanup of the Clearview Landfill, a Superfund site that contaminated parts of the Eastwick section of Southwest Philly and has plagued residents there for decades.

The landfill straddles Darby Creek near 84th Street and Lindbergh Boulevard, and was an unlicensed dump for commercial, industrial, institutional, and municipal waste starting in the early 1950s. The dumping left behind a toxic mix of heavy metals, volatile organic compounds, pesticides, and other compounds that can threaten human health and the environment.

The U.S. Environmental Protection Agency launched a cleanup in 2011 and excavated 4,000 tons of polychlorinated biphenyl (PCB) waste, which was shipped to another facility for disposal. Within the last several years, the EPA also performed a cleanup of 33 residential properties to remove soil contaminated with polycyclic aromatic hydrocarbons (PAHs) and excavated an additional 3,000 cubic yards of contaminated soil in the neighborhood.

The site is in its final cleanup stage, which entails covering 50 acres to contain landfill waste and contaminants, more excavation of contaminated soils, and collecting and treating leachate, contaminated water that leaked from the landfill. In all, the remediation is expected to cost $76.2 million, according to officials.

To recoup part of that cost, the EPA sued Philadelphia and its Redevelopment Authority last week in U.S. District Court. Philadelphia officials had known since 2002 that the city had been named by the EPA as a potentially responsible party for the site. So, the city reached an immediate negotiated agreement on the amount it would pay when the suit was filed.

Mike Dunn, a spokesperson for the city, said in a statement that Philadelphia admitted no liability and that the money will be paid over four years.

Dunn noted that the site no longer poses a “significant immediate risk to public health,” but officials want it cleaned up as soon as possible.

EPA Mid-Atlantic Regional Administrator Cosmo Servidio called the settlement “an important step towards EPA’s goal of accelerating” Superfund cleanups while promoting economic revitalization.

The Clearview Landfill is part of a larger Superfund complex known as the Lower Darby Creek Area. The site consists of the Clearview and Folcroft landfills. The Folcroft Landfill is two miles downstream on Darby Creek and within the John Heinz National Wildlife Refuge at Tinicum. Both landfills operated from the 1950s to the 1970s until ordered closed by the state.

The city’s settlement only applies to the Clearview Landfill, which has long been problematic for Eastwick. Part of Clearview also touches Delaware County.

In the early 1980s, leachate and soil samples showed hazardous PCBs and PAHs were present at the landfill. Into the 1990s, the EPA continued to find signs of new dumping and leachate that had seeped into Darby Creek. By the end of the 1990s, the EPA had launched an investigation of the entire site.

The EPA then expanded its investigation into Eastwick and its recreation center, and found contamination of soil and groundwater.

As a result, the Clearview Landfill and parts of the surrounding neighborhood were added to the National Priorities List, reserved for the worst Superfund cases, and therefore were eligible for cleanup. Subsequently, elevated levels of numerous hazardous substances, including lead, arsenic, and benzo(a)pyrene were found at Clearview.

Many of the same substances were discovered, but at lower levels, at Eastwick City Park, long used by residents. The EPA sampled soil in 105 residential yards and found contaminants in some. It began excavating yards for cleanup and relocating some businesses. Research showed that hazardous substances had been released decades earlier in areas of the neighborhood immediately around the landfill that were owned by the city.

Because Philadelphia had dumped municipal waste, incinerator ash, and residue at the landfill from 1967 to 1973, the federal government considered the city liable for contamination. The Redevelopment Authority, which acquired the original land for Eastwick in 1958, also was named as a defendant in the suit.

Dunn said the final design for the site, once fully remediated, will include a large green space. The landfill cap will not be open to the public, but will be covered in trees and bushes. The Eastwick Park and Recreation facility will also be open.

The city will then add a biking and hiking trail across one side of the cleanup site. It will become part of the East Coast Greenway, which includes 3,000 miles of trails from Maine to Florida. The trail will run through the Heinz refuge and grounds of Philadelphia International Airport.