Aberdeen Proving Ground (Edgewood Area)

Overview

Aberdeen Proving Ground's Edgewood Area covers 13,000 acres in Edgewood, Maryland. The U.S. Army developed and tested chemical agent munitions there from 1917 to the present. That work left behind widespread contamination in soil, sediment, groundwater, and surface water. The site was added to the Superfund National Priorities List on February 21, 1990, and a Federal Facility Agreement signed that same year set up oversight by EPA and the Maryland Department of the Environment.

EPA has identified more than 200 contaminants of concern at the site. These include volatile organic compounds such as trichloroethene, tetrachloroethene, benzene, and vinyl chloride found mainly in groundwater. Metals including arsenic, lead, chromium, cadmium, mercury, and copper appear in soil and groundwater. Polycyclic aromatic hydrocarbons, PCBs (polychlorinated biphenyls), pesticides like DDT and heptachlor, and unexploded ordnance are also present. More recently, PFAS (per- and polyfluoroalkyl substances), chemicals used in firefighting foam, were found in groundwater and soil at levels above EPA screening levels. A PFAS Remedial Investigation began in late 2024.

The U.S. Army leads cleanup across 57 to 58 operable units covering different geographic areas and contamination types. Cleanup methods vary by unit and include engineered caps, excavation, chemical oxidation, pump-and-treat systems, bioremediation, and institutional controls. Records of Decision have been issued for most units. Five-year reviews completed in 2023 and 2025 found that remedies at 32 of 33 reviewed units are currently protective of public health and the environment. Eleven units need additional actions to stay protective in the future, and one unit's protectiveness could not be determined at the time of review. A second five-year review addendum is expected by June 2026. Land use controls are in place at multiple units to prevent residential development and limit exposure to remaining contamination. EPA assessments indicate human exposure is currently under control, though physical construction is not yet complete and the site is not ready for anticipated reuse.

Community members can get involved through the Aberdeen Proving Ground Restoration Advisory Board, which holds quarterly public meetings tentatively on the 4th Thursday of January, March, July, and October from 7 to 9 p.m. Meetings are currently held virtually. Minutes are available at the Aberdeen and Edgewood branches of the Harford County Public Library. The board also maintains a Facebook page with announcements. Residents with questions can contact the Army's Restoration Advisory Board representative. EPA's Community Involvement Coordinator and Remedial Project Manager are also available for questions.