Wildcat Landfill operated in Dover, Delaware from 1962 to 1973, accepting municipal and industrial waste. Operators violated state permits by leaving waste uncovered, scattering metal drums, and dumping into wetlands. That contaminated the site's soil, groundwater, and surface water with heavy metals, organic compounds, and polychlorinated biphenyls, known as PCBs. EPA added the site to the National Priorities List, or NPL, in 1983.
Cleanup was organized into two operable units. The first covered the landfill itself, where workers capped exposed waste with soil, removed drums taken off-site, and installed groundwater monitoring wells. The second addressed Racetrack Pond, a new pond built in an unaffected area to replace lost surface water habitat. A nearby pond was drained and stabilized with vegetation. Physical construction finished in 1992, and all remedial work wrapped up by 1999. Drinking water wells tested in 2001 showed no site-related contamination. EPA deleted the site from the NPL in March 2003.
Contaminants at the landfill include antimony, arsenic, barium, cadmium, chromium, lead, manganese, mercury, nickel, chrysene, and PCBs found in groundwater and soil. Landfill leachate also contains mercury. At Racetrack Pond, surface water contained cadmium, copper, iron, lead, vanadium, and zinc. Human exposure is currently under control, and contaminated groundwater movement has stabilized with no unacceptable discharge to surface water.
Kent County purchased the site in 2005 and converted it into a conservation area. It now hosts Hunn Nature Park, with walking and running trails and forested land used for museum and archaeological research. Institutional controls remain in place, restricting well installation on the landfill and nearby property to monitoring purposes only. Zoning rules also prevent residential development on the site. EPA's 2022 Five-Year Review confirmed the remedy protects human health and the environment in the short term. The agency plans to review soil sampling data and reassess future groundwater and surface water testing. The next five-year review is scheduled for 2027.
Community members can get involved through EPA's Community Involvement Program, which offers ways to engage in cleanup discussions and provide input on decisions. Questions about the site can be directed to the EPA contacts listed for this location.
