Keith Hays: Mapping the PFAS iceberg

Over the past several years, PFAS have made many headlines in both mainstream and water-related publications in the US. This is due to the rapid growth in the discovery of contaminated sites and the mounting evidence of adverse human health effects.

As of July 2020, there are over 2,200 confirmed sites of PFAS contamination across all 50 states. This has grown enormously over the past year and is likely just the tip of the iceberg.

With the potential for a comprehensive clean-up effort to require multiple decades and billions of dollars, PFAS is a topic that’s top of mind for municipal utilities, water technology providers, investors, regulators, and others within the water sector.

States tighten regulations

The current and unenforceable federal health advisory on PFAS is 70 parts per trillion (ppt). However, many health experts deem this to be too high for prolonged exposure.

For this reason, several states that have notable legacies of industrial and military activity are taking the lead on the policy front. The following five states have some of the highest concentrations of sites within their state and some of the more aggressive approaches so far:

• Michigan: PFOS: 16 ppt, PFOA: 8 ppt
• New Jersey: PFOS: 13 ppt, PFOA: 14 ppt
• New Hampshire: PFOS: 15 ppt, PFOA: 12 ppt
• New York: PFOS: 10 ppt, PFOA: 10 ppt
• California: PFOS: 40 ppt, PFOA: 10 ppt.

These approaches are setting the baseline for the longer-term creation of a national market focused on PFAs remediation.

Best available technologies for remediation

To date, the most widely used technique in drinking water remediation at the utility level is granular activated carbon (GAC).

GAC is a well-known and well-used technology for other water treatment purposes. As a result, it often means there is little more than a more frequent bed changeout to the investment already made in a location.

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Ion exchange (IX) resins are another adsorptive technology that is gaining traction as well, with the vendors formulating media with greater specificity in targeting various PFAS compounds. 

Though typically more costly per unit of volume, IX resins often have longer bed contact lifetimes, reducing operation costs (OPEX), and usually require less space. This makes them an option for smaller operations with less available space, or for mobile remediation techniques as well.

Reverse osmosis (RO) filtration is also effective at PFAS removal, but the most expensive option of these three current best available technologies for remediation.