Category: PFAS

Land used for fire-fighting training can remain polluted for decades if aqueous film-forming foams were used. Many older foams contained PFAS, including PFOS and PFOA. These chemicals resist heat, water, and natural breakdown, so they can persist in soil and ground water long after the source has ceased. A site last used for training 30 years ago can still act as a source if PFAS remain bound in soil and then leach into ground water during rain or changes in water level. This means that “old” contamination does not mean “spent” contamination. (US EPA)

If local water tests show PFAS at 40,000 times a recognised safe level, the first aim should not be full land repair. It should be exposure control. That means stopping use of polluted water, supplying clean water, testing private wells and surface water, and fitting treatment where water enters buildings or at the tap. The most proven water treatments are granular activated carbon, ion exchange resin, and high-pressure membranes such as reverse osmosis. These can reduce PFAS in treated water within days or weeks once designed, installed, and run well. Yet they do not destroy PFAS. They move PFAS from water into carbon, resin, brine, or membrane waste, which then needs safe disposal or further treatment. (US EPA)

Repairing the land and aquifer is slower and more uncertain. For soil, the most realistic methods include excavation and disposal, soil washing, thermal treatment, or stabilisation with sorbents such as activated carbon. Excavation can remove a clear “hot spot”, but it can be costly and may only move the waste elsewhere. Stabilisation can bind PFAS in soil and reduce leaching, but it does not remove the chemicals. Thermal methods may destroy some PFAS, but they need high technical control and can raise concern about air emissions and incomplete destruction. ITRC notes that many standard clean-up methods, such as air stripping or bioremediation, work poorly for PFAS because the chemistry is so stable. (pfas-1.itrcweb.org)

For ground water, pump-and-treat can contain a plume and lower PFAS in extracted water, but it tends to require long-term running. This is due to “back diffusion” and slow release from soil, sediment, and less mobile zones. In plain terms, even when polluted water is pumped out and treated, more PFAS may seep back into the water from the surrounding ground. Barriers that contain or adsorb PFAS in the ground may help, but they also need long-term monitoring and may later need renewal. (gov.je)

The likely time scale therefore splits into two parts. Treated household water can improve quite fast if a sound system is installed and maintained. The wider site and aquifer may take many years, and in some cases decades, to reach lower levels. At very high readings, it would be rash to promise quick remediation. A credible plan would require independent site mapping, repeated sampling, clear plume models, immediate clean-water measures, source removal where feasible, long-term treatment, and public reporting. The honest claim is not that the land can soon be made normal. It is that exposure can be reduced while a long, costly, and uncertain clean-up proceeds.

References

Interstate Technology and Regulatory Council. (2025). PFAS technical and regulatory guidance document: Treatment technologies. Interstate Technology and Regulatory Council.

United States Environmental Protection Agency. (2018). Reducing PFAS in drinking water with treatment technologies. United States Environmental Protection Agency.

Tshangana, C. S., Nhlengethwa, S. T., Glass, S., Denison, S., Kuvarega, A. T., Nkambule, T. T. I., Mamba, B. B., & Alvarez, P. J. J. (2025). Technology status to treat PFAS-contaminated water and limiting factors for their effective full-scale application. npj Clean Water, 8, Article 41.

The evidence suggests that PFAS contamination can reduce property value and make resale harder, especially when three things occur together: the contamination affects drinking water or soil, the risk becomes public knowledge, and buyers fear long-term health, legal, or mortgage risk. PFAS compounds matter in property markets because they persist in the environment and can be hard and costly to remove. For that reason, they can create both a physical risk and a market stigma. The problem is not only whether a house can be lived in today. It is also whether a future buyer, lender, insurer, or solicitor will regard the property as safe, saleable, and free from future liability.

A recent economic study of PFAS in drinking water found that public media coverage of PFAS contamination reduced the value of affected homes. The authors used residential sale data and a difference-in-differences design, which compares affected homes with similar homes before and after the contamination became known. They found that high-profile public knowledge of PFAS risk had a negative effect on house prices, and they also found signs of social sorting, where those with more choice could move away while others remained exposed (Marcus, 2024). (ScienceDirect) This is crucial because contamination affects value through both exposure and perception. Even when technical risk remains contested, the market may respond to uncertainty.

The wider evidence on contaminated land supports the same point. Studies of hazardous waste sites and other forms of environmental contamination have long found lower residential values near contaminated sites. Kiel and Williams (2007), in a study of Superfund sites in the United States, note that the negative effect of such sites on local property values has become an established empirical finding. (IDEAS/RePEc) A later meta-analysis found that proximity to severely contaminated waste sites has a strong negative effect on residential property values. It estimated that, after allowing for publication bias, property values rose by about 1.5% to 2.9% for each mile farther from a waste site, for a home located one mile away (Schütt, 2021). (Springer) These figures should not be used as direct estimates for any single estate, but they show that markets price environmental risk.

Water contamination can be severe because it affects daily life. A property may still stand, but its use value changes if the water supply, garden soil, or local environment becomes suspect. Research on well-water contamination found a 10% fall in property value when a test showed a contaminant above detectable limits, compared with homes where tests did not find contamination (Keane, 2024). (drum.lib.umd.edu) Other work on groundwater and water quality has found that buyers respond to water risk, especially where the risk is known, visible, or hard to avoid. (ScienceDirect)

PFAS may create a sharper resale problem than some other pollutants because it raises linked concerns about health, clean-up, legal duty, and disclosure. In the United States, PFOA and PFOS have been designated hazardous substances under CERCLA, which has raised real-estate concerns about liability, due diligence, and transactions, even where regulators say they will focus action on major polluters rather than ordinary owners. (Reuters) This shows how contamination can affect not only price, but also the practical chance of a sale. A buyer may seek a large discount, a lender may hesitate, an insurer may ask questions, and a solicitor may require clear evidence of remediation.

The main lesson is that contamination damages property value through layered risk. There is the direct risk of exposure, the cost and doubt of remediation, the stigma attached to the site, and the fear that a later sale may fail. Where contamination remains unresolved, the market may cease to treat homes as normal homes. They become distressed assets, with value set less by bricks and fittings than by uncertainty, fear, liability, and trust.

References

Keane, J. (2024). Groundwater contamination and property values: A hedonic analysis. University of Maryland Digital Repository.

Kiel, K. A., & Williams, M. (2007). The impact of Superfund sites on local property values: Are all sites the same? Journal of Urban Economics, 61(1), 170–192.

Marcus, M. (2024). Unregulated contaminants in drinking water: Evidence from PFAS and housing markets. Journal of Environmental Economics and Management.

Schütt, M. (2021). Systematic variation in waste site effects on residential property values: A meta-analysis. Environmental and Resource Economics, 78, 375–412.

Taylor, L. O., Phaneuf, D. J., & Liu, X. (2016). Disentangling property value impacts of environmental contamination from locally undesirable land uses. Journal of Urban Economics, 93, 85–98.