PFAS - per- and polyfluoroalkyl substances - are the defining environmental challenge of this decade. These synthetic chemicals, used since the 1950s in everything from firefighting foam to food packaging, are now found in drinking water, soil and groundwater at sites across every continent. Their extreme persistence has earned them the name "forever chemicals" and for good reason: they do not break down in the environment under normal conditions.

For environmental professionals, PFAS contamination presents unique challenges that existing frameworks were not designed to handle. This guide covers the current state of PFAS science, regulation and remediation worldwide.

What Are PFAS?

PFAS is a family of over 14,000 synthetic fluorinated compounds characterized by carbon-fluorine bonds, one of the strongest bonds in organic chemistry. This bond strength makes PFAS resistant to heat, water, oil and biological degradation, which is why they were so useful in industrial and consumer products and why they are so difficult to clean up.

The most studied PFAS compounds include:

  • PFOA (perfluorooctanoic acid) - Used in Teflon manufacturing. Phased out by major manufacturers but persistent in the environment.
  • PFOS (perfluorooctane sulfonate) - Primary ingredient in aqueous film-forming foam (AFFF) used for firefighting. Banned under the Stockholm Convention.
  • GenX (HFPO-DA) - A replacement for PFOA that is now also under regulatory scrutiny.
  • PFBS, PFHxS, PFNA, PFDA - Short- and long-chain PFAS compounds found at contaminated sites.

Sources of PFAS Contamination

PFAS contamination is found at predictable site types worldwide:

Airports and Military Bases

The single largest source of PFAS soil and groundwater contamination globally. AFFF firefighting foam was used extensively for training exercises and emergency response at airports and military installations for decades. In the US alone, the Department of Defense has identified over 700 installations with known or suspected PFAS releases.

Fire Training Areas

Municipal fire departments, industrial fire brigades and petrochemical facilities used AFFF for training. These sites often have the highest PFAS concentrations because foam was repeatedly applied to the same burn pad.

Industrial Manufacturing

Facilities that manufactured or used PFAS in processes: chrome plating, semiconductor fabrication, textile treatment, paper coating and chemical manufacturing.

Landfills

Consumer products containing PFAS end up in landfills. PFAS leaches from waste into leachate, which can contaminate groundwater if containment systems are inadequate.

Wastewater Treatment Plants

PFAS passes through conventional wastewater treatment without degradation. Treated effluent and biosolids (used as agricultural fertilizer in many regions) become secondary PFAS sources.

Global Regulatory Landscape

PFAS regulation is evolving rapidly and varies significantly by jurisdiction. Environmental professionals must track requirements in every market where they operate.

United States

The US EPA finalized Maximum Contaminant Levels (MCLs) for drinking water in April 2024:

  • PFOA: 4 parts per trillion (ppt)
  • PFOS: 4 ppt
  • PFHxS, PFNA, HFPO-DA: 10 ppt individually
  • Mixtures of PFHxS, PFNA, HFPO-DA and PFBS: Hazard Index of 1

CERCLA designation of PFOA and PFOS as hazardous substances enables Superfund enforcement and cost recovery. Several states (Michigan, New Jersey, Minnesota) have established soil and groundwater standards stricter than federal levels.

European Union

The EU Drinking Water Directive (2020/2184) sets limits of 0.1 μg/L for individual PFAS and 0.5 μg/L for total PFAS in drinking water. Five EU member states (Denmark, Germany, Netherlands, Norway, Sweden) submitted a proposal to restrict approximately 10,000 PFAS compounds under REACH. If adopted, it would be the broadest chemical restriction in history.

Australia

The PFAS National Environmental Management Plan (NEMP 3.0) provides guidance values for soil, groundwater and surface water. States apply these through their own regulatory frameworks. Defence sites are the primary focus of investigation and remediation.

Canada

Health Canada's drinking water guideline for PFOA is 200 ppt and PFOS is 600 ppt, though several provinces are moving toward lower limits. The federal government has proposed adding a broad class of PFAS to the Canadian Environmental Protection Act.

Other Jurisdictions

Japan, South Korea, the UK, New Zealand and Brazil have all implemented or are developing PFAS-specific environmental standards. The trend everywhere is toward lower limits and broader compound coverage.

Site Investigation for PFAS

PFAS investigation requires modified approaches compared to conventional contaminant assessments:

Sampling Protocols

  • No Teflon equipment - PFAS sampling requires PFAS-free equipment. No Teflon-lined tubing, no waterproof notebooks with PFAS coatings, no Tyvek suits (some contain PFAS).
  • Field blanks and equipment blanks are critical for detecting cross-contamination
  • Low-flow sampling for groundwater to minimize turbidity and capture dissolved-phase PFAS accurately
  • Sample preservation: HDPE containers with Trizma buffer, ship on ice within hold times

Analytical Methods

  • EPA Method 533 and 537.1 for drinking water (LC-MS/MS)
  • EPA Method 1633 for non-potable water, soil, sediment, fish and biosolids (40 PFAS analytes)
  • Total Oxidizable Precursor (TOP) Assay to estimate total PFAS load including precursors
  • Total Organic Fluorine (TOF) to screen for unknown PFAS compounds

Conceptual Site Model

PFAS behaves differently than conventional contaminants. Key differences:

  • PFAS is highly mobile in groundwater - plumes can extend kilometers from source areas
  • Short-chain PFAS is more mobile than long-chain (harder to contain)
  • PFAS partitions to the air-water interface, concentrating in the capillary fringe
  • Back-diffusion from aquitards can sustain plumes long after source removal
  • Precursor transformation means total PFAS mass can appear to increase over time

Remediation Options

PFAS remediation is limited by the chemical stability that makes these compounds problematic in the first place:

Established Technologies

  • Granular Activated Carbon (GAC) - Effective for long-chain PFAS in groundwater. Requires frequent carbon replacement. Spent carbon must be incinerated or reactivated.
  • Ion Exchange Resins - More selective for PFAS than GAC. Higher upfront cost but lower operating cost for some applications.
  • Soil Excavation - For source areas. Excavated soil must go to facilities capable of high-temperature incineration (>1,100°C).
  • Containment - Engineered barriers and hydraulic control to prevent plume migration while treatment technologies mature.

Emerging Technologies

  • Supercritical Water Oxidation (SCWO) - Destroys PFAS at high temperature and pressure. Pilot-scale demonstrated.
  • Electrochemical Oxidation - Uses boron-doped diamond electrodes to mineralize PFAS. Promising for concentrated waste streams.
  • Sonochemical Treatment - Ultrasonic cavitation breaks PFAS bonds. Energy-intensive but effective in laboratory studies.
  • Photocatalytic Degradation - UV light with catalysts. Early stage research.

Cost Implications

PFAS remediation is expensive by any measure:

  • GAC treatment systems for drinking water: $1 million to $10 million for installation, $200,000 to $1 million annually for operation
  • Source area soil excavation and disposal: $500 to $2,000+ per tonne (limited receiving facilities)
  • Groundwater pump-and-treat with PFAS removal: $500,000 to $5 million annually
  • The US EPA estimates national compliance costs for the new drinking water MCLs at $1.5 billion annually

These costs will drive demand for environmental consulting services for decades.

What Environmental Professionals Should Do Now

  1. Build PFAS capability - Train staff on PFAS sampling protocols, analytical methods and regulatory requirements. This is no longer a niche specialty.
  2. Screen existing sites - If you manage sites with AFFF use history, industrial PFAS applications or proximity to known PFAS sources, add PFAS to your monitoring program now.
  3. Track regulatory changes - Standards are tightening quarterly. What was compliant last year may not be compliant next year.
  4. Manage client expectations - PFAS remediation is not like hydrocarbon cleanup. There are no quick fixes. Help clients understand the long-term nature of PFAS management.
  5. Document the chain of custody - PFAS liability litigation is accelerating globally. Meticulous documentation protects both clients and consultants.

The Road Ahead

PFAS contamination will define environmental consulting for the next 20 to 30 years. The compounds are everywhere, the standards are tightening, the remediation technologies are immature and the costs are enormous. For environmental professionals, this is both a challenge and an opportunity. The firms that build deep PFAS expertise now will be the ones leading the industry when the full scale of this problem becomes apparent.

The science is moving fast. The regulations are moving faster. Stay current or fall behind.