PFAS chemicals, both PFOA and PFOS, present a significant threat to drinking water supplies in the U.S. PFAS travels through soil and leaches into groundwater because it has a high-water solubility. Once it is in the environment, it persists. PFOA and PFOS fails to break down over time in the natural environment. Therefore, cities and towns drawing their drinking water from an aquifer underlying a current or former military base or airport have a high likelihood of contamination.
Technologies Available to Treat Water
Once the “forever chemicals” PFOS and PFOA contaminate a groundwater source, water providers must treat the water to protect public health. Unfortunately, PFAS resist most conventional chemical and microbial treatment technologies. The EPA recommends many technologies with demonstrated effectiveness, including the following:
- Activated Carbon
- Membrane Technologies
- Ion Exchange Resin Treatments
Granular Activated Carbon Treatment
The most common treatment method for PFOA and PFOS contaminated groundwater is extraction and filtration through granular activated carbon. However, because PFOA and PFOS have moderate absorbability, the design specifics are very important in obtaining acceptable treatment.
Other Absorbent Treatments
Other potential adsorbents include: ion exchange resins, organo-clays, clay minerals and carbon nanotubes. Evaluation of these sorbents needs to consider regeneration, as the cost and effort required may be substantial. Other ex situ treatments including nanofiltration and reverse osmosis units have been shown to remove PFASs from water. Incineration of the concentrated waste would be needed for the complete destruction of PFAS.
High Costs to Treat PFOA/PFOS Contamination
Decades of negligent use of PFAS chemicals are causing enormous costs to governments. Federal, state and local governments have only just begun to scratch the surface of identifying PFOA/PFOS contamination. These governmental entities must budget for many related costs including:
- environmental investigations
- remediation and waste disposal
- water filtration and alternative drinking water supplies
- health monitoring and biomonitoring
- wastewater and landfill leachate treatment.
The Department of Defense spent $200 million to study and test for PFAS contamination in drinking water. The DOD estimates a cost of $2 billion of taxpayer money to address the problem.
The Future Costs of PFAS
Regulators and other governmental agencies started identifying PFAS contamination fairly recently. The federal government estimates that billions of dollars will be spent in research and sampling of PFAS contamination. Municipal water providers are each spending millions on filtration systems. Federal, State, and Municipal authorities expect spending to increase as PFAS regulations take effect.