Dwyer Property Ground Water Plume

Overview

The Dwyer Property Ground Water Plume sits on a former explosives manufacturing facility in Elkton, Cecil County, Maryland that has been abandoned since 1972. The U.S. Environmental Protection Agency (EPA) added the site to the Superfund National Priorities List (NPL) in March 2011. The NPL is the federal list of contaminated sites that need long-term cleanup attention. The site is organized into three operable units: a sitewide unit, one focused on soil investigation, and one focused on groundwater investigation.

The main contamination concern is trichloroethylene (TCE) in two separate groundwater plumes. The source of one of those plumes has not been identified. Other groundwater contaminants include tetrachloroethylene (PCE), cis-1,2-DCE, 1,1-DCE, vinyl chloride, carbon tetrachloride, naphthalene, perchlorate, and several other volatile organic compounds (VOCs). Soils and waste materials contain lead and arsenic. Deteriorated drums holding unknown substances are also present, and the site carries a potential risk from buried unexploded ordnance.

Honeywell, the successor to Triumph Explosives, is the potentially responsible party (PRP). The EPA issued a Unilateral Administrative Order to Honeywell in February 2016 to conduct further investigation. Between 2018 and 2022, Honeywell completed three phases of field work, surveying roughly 100 potential areas of interest through munitions surveys, soil sampling, and boring. Phase 1 installed 48 groundwater monitoring wells in 2019, Phase 2 added 12 more in 2021, and Phase 3 monitoring took place in late 2022. Planning for Phase 4 began in 2023 to cover the remaining 115 potential areas of interest. Separately, EPA identified two principal source areas releasing lead and arsenic in 2012. Under EPA supervision, drums and contaminated soils were removed and about 233 cubic yards of waste were disposed of off-site by December 2016, with the removal action running through May 2017.

No cleanup remedy has been selected yet. Physical construction of remedial measures has not begun, and the site is not ready for its anticipated future use. Data are currently insufficient to determine whether human exposure is under control or whether contaminated groundwater migration has stabilized. The land is zoned for business industrial use, and institutional controls restrict residential and other incompatible uses.

Community members can get involved through the EPA's Community Involvement Program. A Community Involvement Plan has been developed for the site. A fact sheet from March 2011 and a community update from August 2023 are available. Site records can be reviewed in person at the Cecil County Public Library Elkton Branch at 301 Newark Ave in Elkton, Maryland, or at the EPA Region 3 office in Philadelphia, Pennsylvania. The library can be reached at 410-996-5600 and EPA Region 3 at 215-814-2396.