Keith Hays on mapping the PFAS iceberg

‘Forever Chemicals’ could reshape the US water treatment market in the long term, writes Keith Hays.

Status of PFAS in the US

Per- and polyfluoroalkyl substances (PFAS), increasingly referred to as “forever chemicals,” are a class of over 4,500 chemical compounds that have been broadly in use for the better part of 70 years across numerous commercial, industrial, and military functions.

Their unnaturally durable carbon-fluorine bonds produce desirable hydrophobic and hydrophilic properties with valuable applications.

Unfortunately, they also have a strong tendency to bioaccumulate in humans, raising the risk for cancers and endocrine-related disorders.

"As of July 2020, there are over 2,200 confirmed sites of PFAS contamination across all 50 states."

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.

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.

"While utilities are focused on granular activated carbon at present, this is likely to shift over time due to innovation and economies of scale."

While utilities are focused on GAC at present, this is likely to shift over time due to innovation and economies of scale. IX resins and RO will get closer in relative price, and also due to the evolution in PFAS testing and regulation.

Mapping the iceberg

At present, the main focus of PFAS remediation is centred on the six main compounds that were included in the EPA's third Unregulated Contaminant Monitoring Rule (UCMR 3). Most of these are longer-chain compounds that are more effectively treated by GAC and IX resins.

As regulatory pressure moves toward shorter chain compounds over time, the cost-effectiveness and attractiveness of a more robust filtration system like RO will increase.

This is a situation that has been borne out recently in North Carolina. Due to industrial production in the Cape Fear region, the area has had significant discharges of smaller chain PFAS compound known as Gen-X in recent years.

In 2018, Brunswick, North Carolina built a $36 million-dollar plant with RO capabilities partly to deal with this contamination.

As regulators are still in the process of identifying sites, measuring concentrations, and advising state environmental departments, the water treatment industry continues to map the ‘iceberg’ of PFAs contamination.

As pioneering states move forward with regulations, forcing utilities to deploy advanced treatment technology, a nascent multi-technology market is expected to emerge that will begin to address this massive contamination challenge.