RemBind® is featured throughout the report as a field-proven PFAS stabilisation technology for the remediation of PFAS in contaminated soil. Several full-scale RemBind^® projects in Sweden, Australia, and the USA are cited, and references to published long-term stability data add further credibility to the technology. The report concludes that stabilisation is increasingly being seen as a “pragmatic and cost-effective option compared with many other soil remediation technologies for PFAS”.

Full-Scale RemBind® PFAS Remediation Projects

The report states that RemBind^® has been used to treat thousands of tonnes of PFAS-contaminated soil at full-scale globally, indicating “increased adoption/acceptance”. This includes using stabilisation as a treatment for onsite reuse or as a pre-treatment for safer landfill disposal. The following projects are highlighted:

• Treatment of 7,000 tonnes of PFAS-contaminated soil at Melbourne International Airport with the addition of 1–2% RemBind^® to stockpiled soil with relatively low PFAS impacts using three different blending methods. PFOS and PFHxS were assessed with 95% to 99.9% reduction achieved, enabling on-site reuse.
• 1,500 tonnes of soil from construction works at a Royal Australian Air Force Base in Townsville. Soil was treated prior to off-site disposal with a special treatment area also constructed at the landfill due to its high environmental sensitivity. 32 target PFAS were assessed with 95% to 99.9% reduction achieved across all analytes tested.
• Stabilisation treatment using 1–2% RemBind^® for around 1,000 tonnes of soil excavated as part of a new petroleum storage tank installation at an active military facility in Sweden.
• Around 3,000 tonnes of PFAS-impacted soil at the Markyard site in Sweden required disposal as part of site redevelopment, but landfills would not accept the material. Following laboratory trials, soil was stabilised with 3–5% RemBind^® to enable acceptance at landfill, with stones and large gravel removed prior to stabilisation and reused. A similar approach was planned for around 60,000 tonnes of soil in future.

Long-Term Stability of PFAS Immobilisation

The report highlights ground-breaking independent research published by Kabiri and McLaughlin (2021), which considers the main environmental factors affecting PFAS sorption over time, including temperature extremes and ionic strength. RemBind^® shows little or no detrimental effects with temperature extremes or changes in ionic strength, and effects of competing ions are also absent or minimal.

A further pivotal publication by Arcadis at a US field site (McDonough et al, 2021) is also heavily cited. This involves the in-situ treatment of soil with RemBind^® and cement, with long-term stability monitored over time. After 3 years of monitoring, less than 0.1% of the PFAS had leached. Since the CONCAWE report was published, data presented by Theresa Guillette (Arcadis) at the 2024 Battelle Chlorinated Conference shows that after 5 years of monitoring, this treatment remains very robust.

Stabilisation of Heavy Metals — Lessons Learned

The report also draws similarities between PFAS contaminants and other heavy metal contaminants such as arsenic and chromium in terms of their chemistry, noting that, in the authors’ experience, stabilisation has been used in the US for more than 50 years with no reported major failures — including for contaminants such as heavy metals, PAHs, PCBs, and dioxins.

References

McDonough, J.T.; Anderson, R.H.; Lang, J.R.; Liles, D.; Matteson, K.; Olechiw, T. Field-Scale Demonstration of PFAS Leachability Following In Situ Soil Stabilization. ACS Omega 2022, 7, 1, 419–429. https://doi.org/10.1021/acsomega.1c04789

Kabiri, S.; McLaughlin, M. J. Durability of sorption of per- and polyfluorinated alkyl substances in soils immobilized using common adsorbents: 2. Effects of repeated leaching, temperature extremes, ionic strength and competing ions. Sci. Total Environ. 2021, 766, 144718. https://doi.org/10.1016/j.scitotenv.2020.144718