Overview
Envirotreat has developed specialist expertise in the remediation of per- and polyfluoroalkyl substances (PFAS) through more than 15 years of research, product development, laboratory testing and commercial field application. The company’s approach combines an understanding of PFAS chemistry with proprietary modified clay technologies designed to immobilise both long-chain and short-chain PFAS in soils and groundwater.
Technical Capability
Proprietary PFASorb® Technology
Envirotreat’s principal remediation technology is PFASorb®, an advanced modified clay (inorgano-organoclay) developed specifically for PFAS treatment. The technology is engineered to address the differing chemical behaviour of PFAS by combining:
- Pillared clay structures containing reactive hydroxy-aluminium polymers
- Controlled organoclay modification using quaternary ammonium compounds
- Adjustable formulations tailored to the target PFAS species
This enables treatment of both:
- Long-chain PFAS (such as PFOS and PFOA), which are more hydrophobic and strongly sorbed to soils.
- Short-chain PFAS (such as PFBA), which are significantly more water-soluble and mobile within groundwater.
The company states that the treatment mechanism combines hydrophobic sorption, electrostatic attraction, Lewis acid-base interactions and hydrogen bonding to immobilise PFAS within the clay matrix.
Soil Remediation Capability
Envirotreat has developed a chemical stabilisation process that combines PFASorb with cementitious and pozzolanic binders to reduce PFAS leachability while producing treated soils suitable for reuse.
Key operational capabilities include:
- Ex-situ and in-situ treatment
- Slurry-based application produced on site
- Conventional earthmoving equipment
- Treatment formulations adjusted to site-specific PFAS chemistry
- Typical additive rates below 5% by volume
The company emphasises that controlling pH during stabilisation is critical to maintaining PFAS adsorption performance.
Groundwater Remediation Capability
For groundwater remediation, Envirotreat has developed proprietary Permeable Reactive Barrier (PRB) systems using modified pillared clays.
These systems are designed to:
- Intercept contaminated groundwater plumes
- Adsorb and immobilise PFAS as groundwater flows through the reactive barrier
- Maintain groundwater permeability without significantly altering groundwater flow
The technology can be configured using different reactive media to treat both hydrophobic and hydrophilic PFAS where mixed contaminant plumes are present.
Integrated Remediation Strategy
A notable capability described in the report is the integration of:
- Source area treatment through PFAS stabilisation.
- Down-gradient groundwater treatment using PRBs.
This approach is intended to:
- Reduce contaminant mass within source zones.
- Prevent continued groundwater contamination.
- Minimise treatment volumes.
- Deliver more cost-effective remediation than treating large areas of low-level contamination.
Research and Development Experience
The report outlines a structured programme of technology development.
Early Development (2010)
Envirotreat began investigating PFAS remediation in 2010 through treatability trials on lagoon sludge contaminated with PFOS from historical firefighting foam use.
Initial testing reportedly reduced PFOS leachate concentrations from 13.2 μg/L to 0.20 μg/L using an early pillared organoclay formulation, demonstrating the potential for clay-based stabilisation.
Product Development
Subsequent development led to the creation of the PFASorb product range, focusing on:
- Long-chain PFAS treatment
- Short-chain PFAS treatment
- Optimisation of organoclay chemistry
- Adjustment of aluminium pillaring
- Refinement of quaternary ammonium intercalation
Additional laboratory research undertaken at the National Brownfield Institute during 2024 further refined formulations for both hydrophobic and hydrophilic PFAS.
Commercial Experience
Redditch Fire Station
The Redditch Fire Station project represents Envirotreat’s first full commercial PFAS remediation project.
The remediation strategy included:
- Targeted treatment of PFOS source areas using PFASorb stabilisation.
- Installation of a permeable reactive barrier to intercept groundwater contamination.
Reported outcomes included:
- Greater than 95% reduction in PFOS leachability from treated soils.
- Greater than 95% reduction in groundwater PFOS concentrations at several monitoring boreholes.
- Demonstration of an integrated source-pathway remediation strategy.
New Inn Fire Station (Pontypool)
Following supplementary investigations that identified PFAS contamination in soils and groundwater, Envirotreat designed and installed a permeable reactive barrier to protect the nearby Afon Lwyd.
The project included:
- Detailed site investigation.
- Delineation of PFAS plume migration.
- PRB design.
- Barrier installation.
- Ongoing groundwater and surface water monitoring.
The report identifies this project as a demonstration of the company’s groundwater remediation capability.
Validation and Quality Assurance
Envirotreat validates its stabilisation technology using recognised granular leach testing methods (BS EN 12457-1), intended to assess both immediate and long-term leachability.
Groundwater remediation is validated through:
- Construction quality assurance.
- Pre- and post-remediation groundwater monitoring.
- Comparison against agreed remediation criteria with regulators.
Regulatory Experience
The report demonstrates familiarity with current and emerging PFAS regulation, including:
- UK Environmental Quality Standards (PFOS).
- Environment Agency guidance.
- European proposals for PFAS groundwater standards.
- Relative Potency Factor (RPF) methodology.
- Development of remediation strategies agreed with UK environmental regulators.
Overall Assessment
The capability statement indicates that Envirotreat has developed a specialist niche in PFAS remediation through sustained research and development, proprietary treatment technologies, and commercial implementation. Its principal strengths lie in combining tailored soil stabilisation with groundwater containment using modified clay technologies, supported by laboratory testing and field applications at contaminated fire station sites. While the report presents encouraging treatment performance and operational experience, much of the supporting evidence is derived from company-led research and case studies, and broader independent validation would further strengthen the demonstrated capability.
Envirotreat’s Technical Capability Document
Technical Scientific Summary
Latest Updated Document: ESL Technical Capability Statement – Treatment of PFAS in Soils and Groundwater (June 2026)
This document presents Envirotreat Solutions Ltd.’s technical approach for the remediation of per- and polyfluoroalkyl substances (PFAS) in contaminated soils and groundwater. It combines current understanding of PFAS environmental chemistry with proprietary remediation technologies, principally PFASorb® modified clay stabilisation and Permeable Reactive Barrier (PRB) systems.
The central thesis is that successful PFAS remediation requires treatment strategies tailored to the differing physicochemical behaviour of long-chain (hydrophobic) and short-chain (hydrophilic) PFAS. The company argues that conventional single-technology approaches are inadequate and proposes an integrated remediation methodology combining source treatment with groundwater interception.
Overall Conclusion
The report presents a technically coherent remediation strategy based on the premise that PFAS treatment must account for the distinct chemistry of different PFAS classes. Its principal innovation is the PFASorb® pillared inorgano-organoclay system, engineered to immobilise both hydrophobic and hydrophilic PFAS through a combination of hydrophobic sorption, electrostatic attraction, Lewis acid–base interactions, and hydrogen bonding. Coupled with permeable reactive barriers for groundwater treatment, the proposed integrated approach is supported by laboratory studies and field applications at former fire station sites, where reported reductions in PFAS mobility and groundwater concentrations exceeded 95% in key monitoring locations. While technically plausible and consistent with established adsorption science, the performance claims would benefit from additional independent, long-term validation.
