Osborne Landfill operated from the 1950s to 1978 in Pine Township, Pennsylvania, accepting industrial wastes such as spent paint, asbestos, solvents, waste oils, and slag. The site covers roughly 15 acres and was added to the Superfund National Priorities List (NPL) in September 1983. It is organized into two operable units (OUs), each targeting a different part of the site.
The contamination spread across several media. Groundwater and leachate contained heavy metals, volatile organic compounds (VOCs), and pentachlorophenol. Soil held arsenic, lead, VOCs, and polychlorinated biphenyls (PCBs). Surface water on the site showed VOC contamination, and nearby wetlands had very low PCB levels. EPA identified 17 specific contaminants of concern, including benzene, trichloroethene, vinyl chloride, lead, chromium, nickel, arsenic, beryllium, and several PCB compounds.
Cleanup has gone through multiple phases. A slurry wall was built around the fill area to a depth of 40 feet, and a clay cap was installed to limit leaching. Construction finished in summer 1997. A public water line was extended in 1994 to serve residents whose private wells had high contamination levels. A leachate collection and treatment system ran as planned and is no longer operating because cleanup levels for that area were achieved. For OU 2, which covers wetland sediment, the selected remedy is monitored natural attenuation, meaning contamination is tracked over time rather than actively removed. Remedial action on the wetland area ran from September 1999 through March 2000.
The site is now listed as Construction Complete. EPA's 2025 Five-Year Review concluded that the remedy continues to protect human health and the environment. Human exposure is currently under control across the entire site, with no unacceptable exposure pathways remaining. Groundwater monitoring continues around the slurry wall and in mine voids. Institutional controls restrict groundwater use, bar new wells, and prohibit mining or mineral removal within a half-mile of the site. Zoning restrictions also prevent residential development inconsistent with current cleanup levels. The site has not yet been deleted from the NPL, and long-term response actions for OU 1 are estimated to continue through the end of 2026.
Community members with questions can contact EPA staff directly. Public records are available at the Grove City Library at 125 West Main Street or at the EPA Region 3 Public Reading Room in Philadelphia. An appointment is required for the EPA office.
