Gallup's Quarry

Overview

Gallup's Quarry is a 29-acre abandoned gravel pit in Plainfield, Connecticut. Chemical wastes were illegally dumped there in the 1970s, and the site was added to the EPA's National Priorities List (NPL) in October 1989. The EPA identified over 80 contaminants of concern across soil, groundwater, and sediment. These include volatile organic compounds (VOCs) such as trichloroethene, tetrachloroethene, benzene, and vinyl chloride. The site also contains polychlorinated biphenyls (PCBs), heavy metals like lead, arsenic, and chromium, pesticides including dieldrin and DDT, and polycyclic aromatic hydrocarbons. Low concentrations of VOCs have also been detected in Mill Brook, located about 500 feet downhill from the site.

The Connecticut Department of Environmental Protection removed waste drums and contaminated soil in the early stages of the response. EPA selected a final remedy in September 1997. That remedy relies on long-term groundwater and surface water monitoring, institutional controls, and monitored natural attenuation, meaning natural processes help break down contaminants over time while the site is watched closely. Physical construction of the cleanup is complete. In 2012, sampling was added for 1,4-dioxane and arsenic to reflect updated cleanup standards. Arsenic monitoring continues today. PFAS compounds were detected in groundwater during November 2020 sampling, but institutional controls prevent anyone from using that groundwater, so the remedy remains protective.

EPA has completed five Five-Year Reviews, most recently in September 2022. The agency has determined that human exposure is under control and groundwater migration is under control. The site is designated sitewide ready for anticipated reuse, meaning cleanup goals for current and future land uses have been met and no unacceptable risks remain. The next Five-Year Review is expected between September and November 2027. The site has not been deleted from the NPL.

Institutional controls are a key part of the cleanup. Zoning restrictions prevent residential use and other activities that could expose people to remaining contamination or damage the cleanup work. These controls will stay in place as long as contamination and cleanup components remain on site. The site has been redeveloped with a 37.5-megawatt biomass power plant that became fully operational in January 2014 and generates enough electricity to power roughly 40,000 homes.

Community members can stay informed through local media, public meetings, and the EPA's Superfund website. Site records are available at the Central Village Library in Central Village, Connecticut, and at the EPA Region 1 records center in Boston, Massachusetts. For questions, two EPA contacts are available: Darriel Swatts, Community Involvement Coordinator, and Taylor Freeman, Remedial Project Manager.