Sussex County Landfill No. 5 is a 37.5-acre former municipal and industrial waste site in Laurel, Delaware. It operated from 1970 to 1979, depositing waste below the water table. The EPA added it to the National Priorities List in 1989 and deleted it in 2001 after completing cleanup work.
Groundwater is the affected medium. The EPA identified five contaminants of concern: 1,2-dichloropropane, 1,4-dichlorobenzene, benzene, vinyl chloride, and trichloroethene. A 1992 investigation found these volatile organic compounds (VOCs) at very low levels. One domestic well north of the landfill tested positive, and that residence received bottled water and a water purification system. Sussex County then built a public water line, completed in September 1995, and nearly all nearby homes now use it. Their domestic wells have been closed.
The EPA issued a No Action Record of Decision in December 1994, meaning no active remedial work was required. Sussex County maintains the landfill cover and monitors groundwater every year. Institutional controls restrict groundwater use and block incompatible land uses such as residential development on the site.
The EPA conducted a Five-Year Review in 2020, which found the remedy protective of human health and the environment. A more recent review completed in February 2025 found short-term protection continues but flagged one outstanding step: groundwater monitoring wells must be sampled for per- and polyfluoroalkyl substances (PFAS), a group of synthetic chemicals. That sampling is expected during routine annual monitoring events before the next review, scheduled for 2030. Human exposure to the known contaminants is under control, and contaminated groundwater shows no unacceptable discharge to surface water.
Community members can engage with EPA staff through the Community Involvement Program. Site documents, including an Administrative Record with 140 remedial files, are available online through EPA's Superfund database. Records can also be reviewed in person at the Laurel Public Library at 101 East 4th Street in Laurel, Delaware, or at EPA Region 3 at 1600 John F. Kennedy Boulevard in Philadelphia, Pennsylvania. Appointments are recommended before visiting either location.
