Key PFAS Insights from Department of Defense Investigations

Montrose’s specialized per- and polyfluoroalkyl substances (PFAS) team is currently investigating over 70 sites across 14 U.S. Department of Defense (DoD) installations, providing us with extensive, real-world expertise in addressing the complex challenges of PFAS contamination. Our collaborations span multiple U.S. Army, Air Force, Navy, Coast Guard, and other federal agencies, positioning us to offer valuable insights for organizations navigating their own PFAS challenges. 

As environmental contamination concerns grow, PFAS continue to present evolving challenges. The landscape surrounding these contaminants resembles a modern-day Wild West, with shifting regulations and evolving guidance. The DoD has been a leader in addressing these substances, beginning its investigations as early as 2013-2014. By committing to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) framework early on, the DoD positioned itself to gain a better understanding of PFAS contamination and develop strategies for managing these risks. This proactive approach has uncovered critical lessons that can help guide the future of PFAS management across sectors. 

In this blog, we’ll share key lessons learned drawn from our ongoing investigations with the DoD, highlighting the strategies and methodologies that have shaped our approach to PFAS contamination. 

Understanding PFAS Contamination at DoD Facilities 

The use of Aqueous Film Forming Foam (AFFF) in DoD aircraft hangars and during firefighting training exercises has played a central role in PFAS contamination. AFFF is an essential firefighting agent designed to suppress flammable liquid fires, but its widespread use has led to significant PFAS impacts at multiple sites. 

Comprehensive CERCLA Phase I Remedial Investigations (RIs) allow our teams to assess the extent of contamination and better understand the environmental conditions at identified release areas. These efforts are crucial for identifying the full nature and extent of PFAS contamination, enabling informed decisions on the best path forward for mitigation and remediation. 

Unpacking the Contamination 

To assess the full scale of PFAS contamination, we employ a multi-faceted investigative process that combines several critical techniques. First, we conduct soil borings at source areas to determine contamination levels. Vertical aquifer borings are then used to sample groundwater at varying depths, helping to estimate the extent of groundwater plumes and providing valuable data for determining the best locations for monitoring wells. 

In addition to groundwater monitoring, our investigations include the installation of both shallow and deep wells for continuous monitoring over time. In sites with appropriate geologic conditions, lysimeters are used to assess soil-source strength by collecting porewater samples, offering insights into how contaminants move through the environment. Our approach also includes surface water and sediment sampling at sites near streams and water bodies to better understand the movement and impact of PFAS in aquatic ecosystems. 

Crafting Comprehensive Conceptual Site Models 

One of the more complex aspects of PFAS investigations is understanding how contamination moves through varying geological conditions. Montrose addresses this by creating Conceptual Site Models (CSMs) to visualize PFAS behavior across a site. These models take into account the geological and hydrogeological conditions of the site, along with interactions between PFAS and legacy contaminants. 

A well-constructed CSM helps to reduce uncertainties associated with contaminant transport and provides a clearer picture of how PFAS is likely to spread. This understanding is crucial for designing effective remediation strategies and for guiding future investigations. 

The Power of In-House Laboratory Analysis 

A key element of our approach is the in-house laboratory analysis conducted at Enthalpy Analytical, where thousands of environmental samples have been analyzed using EPA Method 1633. This capability provides several advantages, including cost efficiencies for the DoD and more reliable, consistent data that reduces performance risks. By having control over the laboratory process, we ensure that analyses are conducted quickly and with the utmost accuracy, supporting timely decision-making throughout ongoing investigations. 

Expanding Our PFAS Response Capabilities 

Our work at over 70 sites across 14 DoD installations has provided us with a comprehensive understanding of the unique challenges posed by PFAS contamination. Through our collaboration with federal agency stakeholders, we’ve gained deep insights into the complexities of managing these contaminants. This experience has shaped our ability to deliver tailored solutions and provides valuable lessons for organizations dealing with similar contamination challenges, whether in the public, private, or municipal sectors. 

Lessons Learned and Emerging Best Practices 

Montrose’s early work in the PFAS investigative space has highlighted several key insights that can help guide future efforts in managing PFAS contamination: 

Early Proactive Engagement

The DoD’s early commitment to PFAS investigations and CERCLA processes has been crucial for understanding the scope of contamination and developing informed management strategies. 

Comprehensive Investigations

A multi-faceted investigative approach, incorporating soil, groundwater, and surface water sampling, provides a more complete understanding of contamination and its movement across environments. 

Tailored Remediation Strategies

Conceptual Site Models (CSMs) have proven essential for predicting PFAS behavior, allowing for more precise and effective remediation efforts. 

In-House Capabilities

Maintaining an in-house laboratory for sample analysis not only improves cost efficiency but also enhances the reliability and timeliness of results. 

As PFAS regulations and environmental concerns continue to evolve, the insights derived from the DoD’s investigations—and from Montrose’s work in collaboration with them—offer valuable lessons for all sectors dealing with contamination. By staying ahead of regulatory changes and leveraging these insights, organizations can take meaningful steps toward effective PFAS management and remediation.