RoseyFields conducted a comprehensive environmental exposure and human health risk assessment to evaluate historic chemical releases from a former automotive component manufacturing plant and an adjacent petroleum service station. We evaluated the long-term environmental impacts and community exposure risks associated with chlorinated solvents—specifically trichloroethylene (TCE) and its degradation product, vinyl chloride—as well as petroleum hydrocarbons, including benzene. Our team investigated how decades of routine manufacturing operations, unpermitted chemical disposal practices, and underground storage tank failures resulted in the widespread release of these volatile organic compounds (VOCs) into the surrounding environment.
To accurately reconstruct historical exposures, our team performed advanced environmental forensics, fate and transport modeling, and pathway analyses. We evaluated multiple complex exposure pathways, including historical fugitive air emissions, soil vapor intrusion, groundwater contamination, and the infiltration of volatile gases into municipal sewer systems with subsequent vapor migration into residential structures. RoseyFields utilized U.S. EPA-preferred air dispersion modeling to calculate ground-level ambient air concentrations over several decades, leveraging economic proxy data to reconstruct historical contaminant fluxes when primary facility emissions records were unavailable. Furthermore, our technical analyses included rigorous statistical evaluations of ambient air, indoor air, and sewer vapor sampling data to establish reliable exposure point concentrations.
Building on these environmental models, RoseyFields characterized the affected population by evaluating the spatial extent of the chemical plumes in relation to the surrounding community. We identified the potential exposure class by aligning historical residential occupancy data, structural vulnerability, and proximity to both the groundwater plume and compromised underground utility corridors. Our team then conducted a rigorous carcinogenic and non-carcinogenic risk assessment utilizing established U.S. EPA methodologies. By calculating cumulative inhalation unit risks and hazard quotients across all identified pathways—including industrial facility emissions, sewer gas migration, and ambient air exposure—we provided a scientifically defensible quantification of the cumulative health risks experienced by the surrounding population over time.
