Environmental Forensic Investigation of Historical PFAS Air Emissions, Wastewater Releases, and Multimedia Environmental Transport from an Industrial Fluorochemical Manufacturing Facility
Project Overview
Per- and polyfluoroalkyl substances (PFAS) have emerged as one of the most challenging classes of environmental contaminants due to their exceptional chemical stability, environmental persistence, mobility, and widespread historical industrial use. Evaluating historical PFAS contamination often requires reconstructing manufacturing operations that occurred decades earlier while integrating engineering, environmental chemistry, atmospheric science, hydrogeology, toxicology, industrial hygiene, contaminant fate and transport, and environmental forensic science. Unlike many traditional contaminants, PFAS may be released simultaneously through multiple environmental pathways, including air emissions, wastewater discharges, land disposal, groundwater migration, and surface water transport, requiring comprehensive multidisciplinary investigations to accurately characterize historical releases and potential exposure pathways (Buck et al., 2011; Cousins et al., 2020).
RoseyFields conducted an environmental forensic investigation involving a large industrial fluorochemical manufacturing operation that had historically produced multiple fluorinated products over several decades. The primary objective was to reconstruct historical PFAS use throughout the manufacturing process, identify significant environmental release mechanisms, evaluate engineering controls and waste management practices, and characterize how PFAS migrated through interconnected environmental media. Rather than focusing on a single contaminant pathway, the investigation examined the combined influence of manufacturing operations, air emissions, wastewater treatment processes, waste disposal practices, groundwater transport, and surface water discharges to develop a scientifically supported conceptual site model describing the complete source-to-receptor pathway.
A major component of the investigation involved evaluating historical manufacturing processes to determine where PFAS were intentionally used, unintentionally generated as reaction byproducts, or formed through degradation of precursor compounds during industrial operations. Historical process records, engineering documentation, production information, and environmental monitoring data were integrated to reconstruct contaminant generation throughout multiple manufacturing units. Particular attention was devoted to understanding how PFAS-containing materials moved through production systems, wastewater treatment operations, emission control equipment, and waste management infrastructure, providing insight into both direct releases and secondary environmental transport mechanisms.
The investigation also evaluated historical engineering controls intended to reduce contaminant releases. Air pollution control equipment, wastewater treatment technologies, activated carbon treatment systems, process modifications, and waste handling practices were examined to determine how changes in industrial operations may have influenced environmental emissions over time. Particular emphasis was placed on understanding the effectiveness and limitations of historical pollution control technologies for PFAS, many of which were originally designed for conventional contaminants rather than highly persistent fluorinated compounds. Evaluating historical engineering decisions provided important context for interpreting environmental monitoring data and reconstructing long-term contaminant releases.
Finally, the investigation integrated atmospheric transport, groundwater migration, wastewater treatment performance, environmental chemistry, contaminant fingerprinting, and exposure assessment into a comprehensive environmental forensic evaluation. Multiple independent lines of scientific evidence were synthesized to reconstruct historical PFAS releases while identifying the environmental processes governing contaminant persistence, migration, and long-term distribution. This multidisciplinary approach reflects the increasingly complex nature of modern environmental forensic investigations involving emerging contaminants and demonstrates the importance of integrating engineering, chemistry, hydrogeology, atmospheric science, and toxicology when evaluating historical industrial contamination (Interstate Technology & Regulatory Council [ITRC], 2024; National Academies of Sciences, Engineering, and Medicine, 2022).
Chemicals of Concern
The principal chemicals of concern evaluated during this environmental forensic investigation were per- and polyfluoroalkyl substances (PFAS), a large class of synthetic fluorinated compounds historically used in fluoropolymer production because of their exceptional surfactant properties, thermal stability, and chemical resistance. These compounds played important roles as polymerization aids, processing agents, and manufacturing intermediates in numerous industrial applications. However, the same carbon-fluorine bond responsible for their desirable industrial performance also makes PFAS among the most environmentally persistent synthetic chemicals known. Once released, many PFAS remain in environmental media for decades, exhibiting minimal degradation while migrating through air, groundwater, surface water, soils, sediments, and biological systems (Buck et al., 2011; Cousins et al., 2020).
Particular attention was devoted to perfluorooctanoic acid (PFOA), which was historically used as a polymerization aid during the manufacture of fluoropolymers and related products. PFOA has become one of the most extensively studied PFAS compounds because of its widespread industrial use, exceptional environmental persistence, and documented human health effects. Numerous toxicological and epidemiological investigations have associated chronic PFOA exposure with increased serum cholesterol, developmental effects, immune system suppression, thyroid dysfunction, liver toxicity, kidney disease, and elevated risks of certain cancers. As a result, regulatory agencies worldwide have established increasingly stringent drinking water standards and environmental cleanup criteria for PFOA, making it a primary focus of environmental forensic investigations involving historical fluorochemical manufacturing (ATSDR, 2021; U.S. EPA, 2024).
The investigation also considered additional fluorinated compounds commonly associated with historical industrial operations, including perfluorooctane sulfonate (PFOS), fluorotelomer compounds, and other fluorinated process intermediates capable of transforming into terminal perfluoroalkyl acids following environmental release. Because historical manufacturing operations frequently produced complex mixtures of fluorinated compounds rather than a single chemical, evaluating the complete PFAS profile provided valuable information regarding contaminant sources, historical manufacturing practices, and environmental transport mechanisms. Differences in compound distribution, chain length, and chemical structure can strengthen source attribution by distinguishing among various industrial processes and release pathways (Buck et al., 2011; ITRC, 2024).
An important aspect of this investigation involved evaluating PFAS behavior within both industrial wastewater treatment systems and atmospheric emission pathways. Unlike many conventional organic contaminants, PFAS are generally resistant to biological treatment and conventional wastewater processes. Instead of being destroyed, these compounds may be redistributed among treated effluent, treatment residuals, activated carbon, and other waste streams. Similarly, elevated process temperatures can cause certain PFAS compounds or precursors to volatilize or become associated with fine aerosols capable of atmospheric transport before depositing onto surrounding environmental surfaces. Consequently, evaluating both wastewater and air pathways is essential when reconstructing historical releases from fluorochemical manufacturing operations (Brusseau, 2018; Stoiber et al., 2020).
The investigation further evaluated the environmental persistence and transport characteristics of PFAS across multiple environmental media. Because these compounds exhibit varying degrees of groundwater mobility, atmospheric transport potential, sorption behavior, and bioaccumulation depending on their chemical structure, contaminant migration cannot be fully understood by examining a single environmental compartment. Integrating environmental chemistry, hydrogeology, atmospheric science, engineering, and contaminant fate and transport provides a more complete understanding of how PFAS move through interconnected environmental systems and ultimately contribute to long-term human and ecological exposure (Anderson et al., 2019; National Academies of Sciences, Engineering, and Medicine, 2022).
Methods
A multidisciplinary environmental forensic investigation was conducted to evaluate historical PFAS releases associated with fluorochemical manufacturing operations and to reconstruct the mechanisms by which these contaminants migrated through air, wastewater, groundwater, and other interconnected environmental media. The investigation integrated industrial engineering, environmental chemistry, atmospheric science, hydrogeology, contaminant fate and transport, analytical chemistry, toxicology, exposure assessment, and environmental history to develop a scientifically supported conceptual site model describing the complete source-to-receptor pathway. Rather than relying on a single line of evidence, multiple independent datasets were synthesized using a weight-of-evidence approach to characterize historical releases, evaluate environmental transport mechanisms, and assess the effectiveness of historical engineering controls (ASTM International, 2021; U.S. EPA, 2024).
The investigation began with a comprehensive review of historical manufacturing operations, engineering documentation, environmental monitoring records, process flow information, waste management practices, and regulatory documentation. Historical production processes were evaluated to identify where PFAS compounds were intentionally used as processing aids, generated as manufacturing byproducts, or formed through degradation of precursor compounds. Particular attention was devoted to understanding how fluorinated materials moved through manufacturing operations, wastewater treatment systems, air pollution control equipment, waste handling practices, and environmental management programs. This historical reconstruction provided the foundation for identifying potential release mechanisms and evaluating how operational changes influenced environmental emissions over time (Buck et al., 2011; Interstate Technology & Regulatory Council [ITRC], 2024).
Engineering evaluations focused on identifying the principal pathways through which PFAS could enter the environment during routine industrial operations. Process equipment, emission sources, wastewater treatment systems, activated carbon treatment processes, thermal treatment technologies, and historical pollution control equipment were evaluated to determine their effectiveness in managing persistent fluorinated compounds. Particular emphasis was placed on understanding the limitations of conventional treatment technologies that were originally designed to remove traditional industrial contaminants rather than chemically stable PFAS. Engineering assessments also considered the influence of operating temperatures, volatilization, aerosol generation, adsorption processes, and treatment residual management on long-term contaminant releases (Stoiber et al., 2020; U.S. EPA, 2024).
Hydrogeologic and atmospheric evaluations were performed to characterize contaminant migration following environmental release. Groundwater investigations incorporated available hydrogeologic information, groundwater monitoring data, hydraulic gradients, and conceptual groundwater flow models to evaluate the migration of dissolved PFAS within the subsurface. Simultaneously, atmospheric transport evaluations examined the potential movement of PFAS-containing aerosols and volatilized fluorinated compounds through ambient air before deposition onto surrounding environmental surfaces. Evaluating both groundwater and atmospheric pathways provided a more comprehensive understanding of contaminant transport than considering either environmental medium independently, reflecting the complex behavior of PFAS within interconnected environmental systems (Freeze & Cherry, 1979; Anderson et al., 2019).
Finally, environmental monitoring data, engineering evaluations, hydrogeologic analyses, atmospheric transport principles, contaminant fingerprinting, toxicological literature, and exposure pathway assessments were integrated into a comprehensive conceptual site model describing the historical occurrence, migration, and persistence of PFAS. Comparing contaminant distributions across groundwater, surface water, air, soils, and other environmental media strengthened source attribution while reducing uncertainty associated with individual datasets. This multidisciplinary environmental forensic framework provides a scientifically rigorous approach for evaluating historical industrial contamination and supports environmental consulting, regulatory investigations, remediation planning, environmental due diligence, and expert witness services involving complex PFAS contamination scenarios (National Academies of Sciences, Engineering, and Medicine, 2022; Brusseau, 2018).
Results
The environmental forensic investigation demonstrated that multiple independent lines of scientific evidence supported a conceptual model in which historical fluorochemical manufacturing activities contributed to PFAS releases through several interconnected environmental pathways. Rather than identifying a single mechanism of release, the investigation found that routine manufacturing operations, wastewater management practices, process emissions, and historical waste handling collectively influenced the long-term environmental distribution of PFAS. Integrating engineering evaluations, environmental chemistry, hydrogeology, atmospheric transport, and historical operational information provided a scientifically robust framework for understanding contaminant migration and source attribution over multiple decades (U.S. EPA, 2024; Interstate Technology & Regulatory Council [ITRC], 2024).
Evaluation of historical manufacturing operations demonstrated that PFAS could enter the environment through both controlled and uncontrolled emission pathways. Engineering assessments indicated that routine industrial processes involving elevated temperatures, chemical processing, material handling, and wastewater management created opportunities for PFAS releases to both air and water. Historical pollution control technologies were designed primarily to reduce conventional air pollutants and wastewater contaminants and were not specifically engineered to capture or destroy highly persistent fluorinated compounds. Consequently, the investigation demonstrated the importance of evaluating historical engineering controls within the context of current scientific understanding of PFAS chemistry rather than assuming conventional treatment systems were equally effective for these emerging contaminants (Buck et al., 2011; Stoiber et al., 2020).
The investigation further demonstrated that air emissions represented an important environmental transport pathway that complemented groundwater and wastewater migration. Engineering evaluations and atmospheric transport principles indicated that fine PFAS-containing aerosols and volatilized precursor compounds could disperse beyond manufacturing areas before depositing onto surrounding soils, surface waters, vegetation, and buildings. Once deposited, these contaminants could infiltrate underlying soils, migrate into groundwater, or accumulate within environmental reservoirs that continue to influence contaminant occurrence long after the original emissions ceased. This multimedia transport behavior illustrates why evaluating atmospheric deposition alongside groundwater investigations provides a more complete understanding of historical PFAS contamination than evaluating individual environmental media independently (Anderson et al., 2019; U.S. EPA, 2024).
Hydrogeologic analyses demonstrated that groundwater served as a significant long-term transport mechanism for dissolved PFAS following environmental release. Groundwater monitoring data, conceptual hydrogeologic models, and environmental chemistry collectively indicated that contaminant migration was influenced by regional groundwater flow patterns, aquifer characteristics, hydraulic connectivity, and the exceptional mobility of many PFAS compounds. The investigation also demonstrated that interactions among groundwater, surface water, wastewater infrastructure, and engineered drainage systems contributed to complex contaminant transport pathways that evolved over extended periods. Integrating hydrogeology with environmental chemistry substantially improved interpretation of observed contaminant distributions and strengthened the development of a scientifically supported conceptual site model (Freeze & Cherry, 1979; Fetter, 2018).
Finally, the investigation demonstrated the value of combining environmental chemistry, engineering, hydrogeology, atmospheric science, toxicology, and environmental forensic analysis within a multidisciplinary weight-of-evidence framework. No individual dataset independently characterized the full extent of historical PFAS releases; however, integrating historical manufacturing information, engineering evaluations, environmental monitoring, contaminant fingerprinting, groundwater investigations, and atmospheric transport principles produced a comprehensive scientific understanding of contaminant fate and transport. This integrated methodology provides a technically rigorous foundation for environmental consulting, regulatory investigations, remediation planning, environmental due diligence, and expert witness evaluations involving complex historical industrial contamination and emerging environmental contaminants (National Academies of Sciences, Engineering, and Medicine, 2022; ASTM International, 2021).
Conclusions
This environmental forensic investigation demonstrated that evaluating historical PFAS contamination requires a comprehensive, multidisciplinary scientific approach that integrates industrial process engineering, environmental chemistry, hydrogeology, atmospheric science, contaminant fate and transport, analytical chemistry, toxicology, and exposure assessment. Because fluorochemical manufacturing operations may release PFAS through multiple environmental pathways simultaneously, investigations that focus exclusively on groundwater, wastewater, or air emissions alone may underestimate the complexity of historical contaminant migration. By synthesizing multiple independent lines of scientific evidence, the investigation developed a technically robust conceptual site model describing the long-term environmental behavior of PFAS from historical industrial operations through interconnected environmental systems (U.S. EPA, 2024; Interstate Technology & Regulatory Council [ITRC], 2024).
The investigation demonstrated that historical manufacturing processes, wastewater treatment operations, and air emission pathways should be evaluated collectively rather than independently when reconstructing PFAS releases. Engineering assessments illustrated that conventional pollution control technologies developed for traditional industrial contaminants were not specifically designed to capture or destroy highly persistent fluorinated compounds. Consequently, historical treatment systems may have altered the transport pathways of PFAS without eliminating them from the environment. Evaluating the performance and limitations of these engineering controls within the context of modern PFAS science provides a more accurate understanding of historical environmental releases and long-term contaminant persistence (Buck et al., 2011; Stoiber et al., 2020).
The investigation further demonstrated the importance of integrating atmospheric deposition, groundwater migration, and surface water interactions into a unified environmental forensic evaluation. PFAS released through industrial air emissions may subsequently deposit onto soils, vegetation, surface waters, and other environmental surfaces before migrating into groundwater or other environmental reservoirs. Likewise, wastewater treatment systems, residual waste management practices, and historical disposal activities may create additional pathways that contribute to contaminant redistribution over time. Evaluating these interconnected transport mechanisms substantially improves source attribution and provides a more scientifically defensible interpretation of environmental monitoring data than evaluating individual media in isolation (Freeze & Cherry, 1979; Brusseau, 2018).
This case study highlights the increasingly important role of environmental forensic science in investigating historical industrial contamination involving emerging contaminants such as PFAS. By integrating historical process reconstruction, engineering evaluations, environmental chemistry, hydrogeology, atmospheric transport, contaminant fingerprinting, exposure science, and toxicology, RoseyFields provides scientifically rigorous evaluations capable of addressing complex environmental investigations involving persistent fluorinated compounds. These multidisciplinary investigations support environmental consulting, regulatory investigations, remediation planning, environmental due diligence, and expert witness services by providing objective, evidence-based scientific analyses that improve understanding of contaminant sources, environmental transport, and potential human and ecological exposure while remaining consistent with current environmental science and accepted forensic methodologies.
This investigation was conducted under the direction of Dr. Paul Rosenfeld, an environmental scientist and environmental forensic expert with extensive experience in PFAS investigations, fluorochemical manufacturing contamination, industrial air emissions analysis, wastewater release evaluation, contaminant fate and transport, and human health exposure assessment. Dr. Rosenfeld’s work focuses on complex environmental contamination matters involving historical industrial operations, PFAS source identification, fluoropolymer and fluorochemical manufacturing processes, atmospheric deposition, wastewater treatment and residuals management, groundwater and surface water migration, contaminant fingerprinting, and long-term multimedia exposure pathways affecting surrounding communities. His expertise includes reconstructing historical release mechanisms through the integration of industrial process engineering, environmental chemistry, hydrogeology, atmospheric science, contaminant mass balance, groundwater and surface water evaluation, toxicology, exposure science, and regulatory analysis to determine whether historical manufacturing practices and engineering controls are consistent with observed environmental conditions and potential human health impacts. Through RoseyFields LLC, Dr. Rosenfeld provides environmental forensic analysis, environmental due diligence, regulatory and compliance support, remediation evaluation, toxic tort and personal injury case assessment, and expert witness testimony involving PFAS contamination, industrial wastewater releases, fluorochemical manufacturing emissions, groundwater and surface water impacts, atmospheric deposition, and long-term environmental and human health risks associated with persistent fluorinated compounds.
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