The site is located just downstream of a bridge that conveys East Washington Street traffic across the Ten Mile River in North Attleborough, Massachusetts. The Ten Mile River then flows directly to Falls Pond, which is a popular waterbody for recreating (particularly kayaking). The site is in a densely settled area and is bordered by single family residences, an apartment complex, a gas station, an autobody shop, a car dealership, and many other establishments. Two sheens have been identified and reported at this particular location on the Ten Mile River since 2020. The sheen generally seems to originate from below or directly downstream of the bridge, which also serves as the terminus of several stormwater drainage pipes. These outfalls then flow under the bridge into the Ten Mile River and Falls Pond, but no oil has ever been detected either in the outfalls themselves or in the subsurface stormwater drainage system (the system was accessed via manholes by the Massachusetts Department of Environmental Protection (MassDEP) and the Massachusetts Department of Transportation (MassDOT)). MassDEP conducted thorough investigation of the incident in 2020 and 2023 to identify the source, but no source was identified. MassDEP requested EPA assistance to respond to the sheen and identify the source in July 2023.
