Q&A: PFAS During Phase II ESAs – Risks and Key Considerations

If a Phase I Environmental Site Assessment (ESA) identifies a PFAS-related Recognized Environmental Condition, the first question is typically: how should we address PFAS concerns?

One of the earliest decisions is whether to conduct PFAS sampling. In some cases, collecting environmental samples may clarify risk and support redevelopment planning. In other situations, sampling may create regulatory obligations that are disproportionate to the actual exposure risk.

Key Takeaways

• PFAS identified in a Phase I ESA requires careful evaluation before Phase II sampling, as testing can introduce regulatory and liability risks.
• The decision to sample depends on site use, exposure pathways, and potential impacts on redevelopment and compliance.
• Interpreting PFAS results is complex due to inconsistent regulations and varying guidance levels.
• PFAS sampling requires strict protocols to prevent cross-contamination and ensure reliable data.
• A strategic Phase II approach helps balance risk, cost, and regulatory considerations while minimizing delays.

What should be considered before PFAS sampling in a Phase II ESA?

Project teams should carefully evaluate current and future site uses, potential exposure pathways, and data implications before moving forward. For properties that will be redeveloped, prospective purchasers should understand the relevant regulatory touchpoints, identify when PFAS sampling may be required, and, if it isn’t required, when voluntary sampling may trigger additional regulatory requirements and project delays.

Langan’s PFAS team routinely helps clients weigh these considerations and develop solutions that are aligned with project objectives, regulatory requirements, and risk tolerance.

How should PFAS sampling results be interpreted in a Phase II ESA?

Interpreting PFAS sampling results can be as challenging as determining whether to conduct sampling in the first place. Many states have not established enforceable cleanup standards, leaving consultants and property owners to rely on federal health advisories, screening levels from other jurisdictions, or risk-based evaluations.

Understanding how regulators will likely view and apply these benchmarks is critical to both avoiding unintended consequences and appropriately managing risk if PFAS is identified. Some states have no mechanism for obtaining relief of liability for PFAS-related impacts.

If PFAS is confirmed, findings may influence development design or trigger additional investigations, remediation, or regulatory requirements. Addressing these considerations early can help minimize project delays and unexpected costs.

What are the requirements for PFAS sampling during a Phase II ESA?

PFAS sampling requires specialized field protocols, as standard equipment and everyday products can introduce false positives. All materials must be verified PFAS-free, which can create unexpected challenges. Field staff, including subcontractors, must avoid certain personal care products, wear specific clothing, and follow strict handling procedures to protect data integrity.

Quality assurance/quality control measures, such as field blanks and equipment blanks, should also be considered to avoid cross-contamination.

What is the goal of PFAS evaluation in a Phase II ESA?

Ultimately, Phase II ESA PFAS evaluations help inform decision-making. With the right strategy and right team in place, PFAS findings can be managed in a way that balances risk, cost, regulatory considerations, and long-term project goals.

Langan’s PFAS experts understand the importance of striking that balance, and build on this experience to help clients confidently navigate PFAS challenges across every stage of their projects.

PFAS During Phase II ESAs FAQ

Should PFAS be included in a Phase II ESA?

PFAS are not always required to be included in a Phase II Environmental Site Assessment, but they should be considered when a Phase I ESA identifies potential PFAS-related concerns. The decision depends on site history, regulatory requirements, and potential exposure risks. In some cases, including PFAS can provide clarity for redevelopment, while in others, it may introduce additional regulatory obligations.

When is PFAS sampling required in a Phase II ESA?

PFAS sampling may be required when state regulations, site conditions, or known historical uses indicate a potential risk. This is often the case for sites with firefighting foam use, industrial operations, or known PFAS contamination. In jurisdictions without clear requirements, sampling may still be considered based on project goals and risk tolerance.

What risks are associated with PFAS sampling during due diligence?

PFAS sampling during due diligence can trigger regulatory scrutiny, potential liability, and additional investigation or remediation requirements. In some cases, identifying PFAS contamination may complicate transactions, delay redevelopment, or increase project costs. It is important to weigh the benefits of data collection against the potential regulatory and financial implications before proceeding.

Chelsea Haglage is an Ohio Voluntary Action Program Certified Professional and environmental scientist in Langan’s Cleveland office with over 12 years of experience. Her expertise includes due diligence activities, surface logging, environmental sampling, on-site health & safety, and construction oversight for remediation projects. Throughout her career, Haglage has conducted due diligence for projects in Ohio, Michigan, Pennsylvania, New York, New Jersey, Massachusetts, Missouri, Kansas, Texas, and California.