The Paoli Rail Yard is a 28-acre former rail maintenance facility in Paoli, Chester County, Pennsylvania. Electric rail cars were serviced there for decades, and dielectric fluids containing polychlorinated biphenyls (PCBs) were released at the yard and migrated to nearby homes and streams. The site was added to the National Priorities List (NPL) in August 1990. The NPL is the federal government's list of the most serious hazardous waste sites in the country.
Seven contaminants of concern have been identified at the site. Aroclor 1260, a type of PCB compound, was found in buildings, soil, and sediment on non-railyard property. Groundwater contamination includes benzene, ethylbenzene, toluene, and mixed xylene isomers. PCBs are the main driver of cleanup decisions at this site.
Cleanup work unfolded in several phases. A removal action completed in 1988 pulled 700 tons of contaminated soil from residential properties and put erosion controls in place. The main remedy, chosen in July 1992, called for excavating heavily contaminated soils from the rail yard, treating them, and placing them in a lined containment cell with an impermeable cap. About 10,200 cubic yards of stream sediments and residential soils, along with 28,000 cubic yards of rail yard soils, went into that containment cell. Stream cleanup continues through natural flushing aided by an engineered basin, where sediments are vacuumed out four times a year and after significant rain events. Residential properties with PCB levels below 2 parts per million on average were cleared for unrestricted use. Properties above that level were remediated. Construction activities finished on July 12, 2005, and the site achieved ready-for-anticipated-use status in March 2011. Institutional controls on the rail yard property restrict groundwater use and prohibit residential or agricultural development. Surrounding residential and commercial properties carry no such restrictions.
Ongoing work is limited to maintaining the perimeter fence, asphalt cap, and stormwater detention basins on the rail yard property. Crews also maintain sediments and vegetation in the lower portions of Cedar Hollow Creek and Hollow Road Creek. A sediment basin near Chester Valley Trail is cleaned out quarterly using a vacuum truck. The most recent Five-Year Review was completed on April 17, 2026, confirming the remedy continues to protect public health and the environment. Groundwater monitoring continues to verify that contamination stays within the original area.
Community members with questions can contact the EPA's Community Involvement Coordinator or Remedial Project Manager. Site records are available online or in person at the Paoli Public Library at 18 Darby Road in Paoli, or at the U.S. EPA Region 3 office in Philadelphia. Appointments to view records can be scheduled by calling (215) 814-2396.
