The Croydon TCE site covers 3.5 square miles of residential, commercial, and industrial land in Bristol Township, Bucks County, Pennsylvania. TCE and related volatile organic compounds (VOCs) were discovered in the groundwater in 1985. No source for the contamination has been identified. The site was added to EPA's National Priorities List (NPL) in June 1986 and divided into two operable units, which are separate geographic areas addressed through distinct cleanup steps.
Thirteen contaminants of concern have been identified in the groundwater. These include chlorinated solvents such as trichloroethene, tetrachloroethene, 1,1,1-trichloroethane, 1,1-dichloroethene, and vinyl chloride, as well as chloroform, 1,1-dichloroethane, and the pesticides dieldrin and p,p'-DDT. Contamination has also been detected in Hog Run Creek, a tributary of the Delaware River used for recreation. This may pose risk to fish, waterfowl, and game animals, and to people who eat affected wildlife or come into contact with contaminated water.
Cleanup began with an emergency water line installed in 1989 and 1990, connecting affected homes and businesses to clean water from Bristol Borough. From 1994 to 1995, EPA built a groundwater extraction and treatment system that pumped contaminated water from about 55 feet deep, treated it through air stripping and activated carbon filtering, and discharged it to Hog Run Creek. That system ran until March 2009, when contamination levels dropped low enough to stop extraction. The Pennsylvania Department of Environmental Protection took over monitoring in 2006. Between 2017 and 2018, the state tested injections of nutrients and methane to encourage natural bacterial breakdown of TCE. This produced a 50 percent initial reduction in concentrations, but levels rebounded afterward.
EPA currently reports that human exposure is under control and groundwater migration has been stabilized. Physical construction is complete across the entire site, and the site has been designated sitewide ready for anticipated reuse. A large portion has been converted into the Croydon Woods Nature Preserve, which opened in 2019. The most recent five-year review, completed in December 2021, found the remedy continues to protect human health and the environment in the short term. The next five-year review is expected by December 2026. A final remedy selection for Operable Unit 2 is estimated between September and November 2027.
Community members can get involved through EPA's Community Involvement Program. The upcoming five-year review offers an opportunity to provide input. Community questions can be directed to the Community Involvement Coordinators assigned to the site. For technical questions, contact the Remedial Project Manager.
