Tackling PFAS: The Regulatory Reality and the Path to Sustainable Site Development

Insights from RSK Geosciences ahead of UKELA 2025.

The awareness of PFAS – per- and polyfluoroalkyl substances, often referred to as “forever chemicals” – has grown significantly in recent years, bringing these persistent environmental contaminants into the public eye and onto the regulatory agenda. But as attention increases, so does the pressure on landowners, developers, and consultants to manage associated risks responsibly and in alignment with evolving legal frameworks.

At RSK Geosciences, we work closely with clients to understand and navigate the commercial and regulatory implications of PFAS in the built and natural environment. Ahead of the UK Environmental Law Association (UKELA) 2025 conference, our specialists will be discussing key learnings from recent projects where PFAS has been a central issue – and where regulation, liability and sustainable development goals intersect.

 

PFAS-free? Let’s get real

There is growing public and political demand for sites to be “PFAS-free” – a term we challenge as technically unrealistic. Given the widespread historical use and environmental persistence of PFAS, these substances are now present in soils, groundwater and even rainfall across much of the world. While their presence may be at low concentrations, achieving truly “PFAS-free” conditions is often not feasible or scientifically justifiable.

Instead, our approach focuses on managing PFAS risk to levels that are as low as reasonably practicable, within the context of site use, environmental sensitivity, and sustainability objectives.

The regulatory disconnect

One of the biggest challenges we face in supporting clients through PFAS issues is the lack of consistency across regulatory bodies. Requirements and risk tolerance vary by region, authority and land use classification. In some cases, PFAS is treated with greater urgency than other, more common contaminants, despite limited evidence of immediate health risk at the concentrations typically found on site.

This disparity can lead to project delays, increased legal exposure, and significant cost escalation – particularly for developers operating across multiple sites or regions.

We’re also seeing an emerging regulatory stance in some jurisdictions that pushes for PFAS exclusion altogether, with limited flexibility. While well-intentioned, these expectations can be difficult to meet without undermining the delivery of sustainable, economically viable development.

 

A call for collaboration

To break the deadlock, we need more than technical solutions. We need collaborative, transparent dialogue between regulators, consultants, landowners, and legal advisors. We also need to share data and experience across sectors to develop more consistent and pragmatic standards.

At UKELA, our team will be discussing real-world case studies where this collaborative model has helped resolve PFAS-related planning and permitting issues. These include:

  • Regulation 61 Environmental Permitting at operational aviation sites

  • Assessment and mitigation of PFAS liabilities on brownfield redevelopment projects

  • Advising on financial and liability risk where PFAS has commercial implications for acquisitions or site disposals

 

Our commitment

RSK Geosciences continues to invest in PFAS knowledge and capability across our environmental consultancy teams. From site investigation and risk assessment to stakeholder engagement and remedial design, we offer a joined-up approach that delivers confidence, compliance, and clarity – no matter how complex the challenge.

 

📩 Want to know more? get in touch to speak to one of our PFAS specialists.