EPA Superfund site
LOWER NEPONSET RIVER
Human exposure is NOT currently under control
Data limitations: Proximity to a Superfund site boundary does not mean your property is contaminated. EPA site boundaries show the area designated for cleanup, not the full extent of contamination. Groundwater plumes can extend beyond site boundaries. This tool shows publicly available EPA federal data. It is not affiliated with or endorsed by EPA, and is not a substitute for a professional environmental assessment.
About this site's exposure pathways
As of May 2026, the Lower Neponset River Superfund site is considered ‘Current Human Exposure Not Under Control’ (HENC). Polychlorinated biphenyls (PCBs) in river sediment and adjacent floodplain soils remain above risk‑based levels. The Massachusetts Department of Public Health (MDPH) maintains a fish‑consumption advisory for the Neponset River; residents are advised not to eat fish from this reach and to follow MDPH guidance. EPA and state/local partners are implementing interim risk‑reduction measures (advisories, outreach, and early cleanup actions) while long‑term cleanup planning continues.