Picatinny Arsenal is a 5,900-acre weapons manufacturing and research facility in Rockaway Township, Morris County, New Jersey. It was added to EPA's Superfund National Priorities List in February 1990 after more than 150 years of industrial activity left widespread contamination across the site. Cleanup is organized into 38 operable units covering different geographic areas and contamination types. Several units have finished remedial action, but construction is not complete sitewide, and the site has not been deleted from the National Priorities List.
Contamination affects groundwater, soil, surface water, sediment, and fish tissue. Groundwater plumes contain volatile organic compounds (VOCs) such as trichloroethene, tetrachloroethene, and benzene, along with heavy metals including arsenic, lead, chromium, and cadmium. The military explosive RDX has also been detected in groundwater. Soil contains dioxins, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, and metals at various locations. Game fish in on-site water bodies carry elevated levels of mercury, PCBs, and arsenic, creating significant health risk from eating them, particularly for pregnant women and women of childbearing age. In 2018, per- and polyfluorinated alkyl substances (PFAS), chemicals used in firefighting foams, were found in drinking water above EPA health limits. The Army provided bottled water to base residents and installed temporary treatment. A remedial investigation for PFAS began in February 2024.
The U.S. Army is the lead federal agency responsible for cleanup, with EPA overseeing compliance under CERCLA (the Comprehensive Environmental Response, Compensation, and Liability Act). Cleanup actions completed or underway include soil removal, engineered soil caps, groundwater treatment using carbon substrate injection to break down VOCs, a zero-valent iron permeable reactive barrier to intercept contaminant plumes, and monitored natural attenuation. Unexploded ordnance is being addressed through clearance procedures and feasibility studies. Institutional controls restrict residential land use where low-level contamination remains, and fish consumption guidelines limit exposure through contaminated fish. EPA's most recent five-year review, completed in August 2021, confirmed that remedies in place protect public health and the environment. EPA has determined that human exposure and groundwater migration are under control.
Community members can get involved by attending Restoration Advisory Board (RAB) meetings held throughout the year. The RAB brings together the Army, regulatory agencies, and the public to discuss site restoration. General cleanup questions can be directed to the RAB contact line at 973-724-6364. Site records are available at the Picatinny Arsenal Installation Restoration Program Office, the Rockaway Township Library, Morris County Library in Whippany, and EPA's Superfund Records Center in New York City.
