Dr. Bahman Bani, Ph.D., P.Eng.

Tailored Multi-Stage Remediation to Address PFAS Challenges at a Commercial Airport

Dr. Bahman Bani, Ph.D., P.Eng., Global Emerging Contaminants Market Solution Lead, Jacobs

The evolving regulatory landscape for per- and polyfluoroalkyl substances (PFAS) presents significant challenges for environmental professionals tasked with managing contamination at legacy and active industrial or commercial sites. Increasingly stringent federal and provincial regulations require adaptive strategies to address site-specific complexities while ensuring compliance and minimizing risk. This presentation highlights the challenges and solutions associated with implementing effective PFAS program management, emphasizing the need to balance technical, regulatory, stakeholder, and funding considerations. A case study from a commercial airport in Canada illustrates the development of an innovative remediation strategy and an adaptable management framework, addressing PFAS contamination in groundwater and soil under diverse hydrogeological and climatic conditions.    The project developed a comprehensive PFAS management program encompassing site characterization, source identification, risk assessment, remedial investigation, treatment evaluation, and interim remedial actions, such as hotspot source removal. A site-specific risk assessment was conducted using the state-of-the-art innovative read-across new approach methods (NAMs) to defensibly assess risk of PFAS parameters without regulatory toxicity values. These findings informed the establishment of site-specific risk-based criteria to guide remediation, reducing reliance on evolving generic regulatory standards. A dynamic and data-driven approach integrated hydrogeological modeling, visual 3D conceptual site model (CSM), and stakeholder engagement to inform decision-making. A multi-stage remediation approach expedited remedial efforts by targeting PFAS mass removal and soil stabilization in critical hotspot areas and stabilizing PFAS groundwater plume migration at site boundary, while concurrently conducting risk assessments. The approach relied on data-driven modeling using 3D Earth Volumetrics Studio (EVS) to strategically target bulk PFAS mass in soil and shallow groundwater for maximum removal efficiency within the allotted budget.     Preliminary findings suggest that the hydrogeological complexity, including shallow bedrock conditions, combined with the unique chemical behavior of PFAS, necessitated customized treatment and risk management strategies. Early results demonstrated the potential of dynamic and data driven approach to reduce PFAS mass in soil by up to 80%, while significantly mitigating PFAS migration in shallow groundwater to a downgradient offsite receptor. Key lessons highlight the importance of integrating high-resolution site characterization techniques, advanced analytical methods and hydrogeological modeling to understand PFAS fate and transport, enabling targeted and efficient dynamic remediation efforts. The dynamic decision-making framework proved essential for adapting to evolving regulatory thresholds and site conditions, ensuring the program’s continued effectiveness and compliance. Furthermore, active stakeholder engagement builds trust and fostered collaboration, enhancing the program’s acceptance and alignment with operational and funding requirements.    By the time of presentation, additional data will be available on post-remediation performance. This work underscores the importance of adaptive, data-driven approaches to PFAS management, providing a roadmap for navigating the challenges of a dynamic regulatory landscape while addressing stakeholder concerns and environmental risks.  

Dr. Bahman Bani is a senior environmental remediation engineer with over 15 years of experience in soil and groundwater remediation across Canada and internationally. He has extensive expertise in environmental site assessments, hydrogeological investigations, PFAS remediation, and risk management planning. Dr. Bani has led numerous projects involving innovative remediation strategies for federal and provincial contaminated sites, including PFAS-impacted environments.