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PFOS in Local Drinking Water, so What?

By Richard D. Smith | Posted October 5, 2023

Water is in the headlines worldwide: Too much water in the forms of mega storms, devastating floods and catastrophic dam failures, too little during torturous droughts and rapid depletion of natural aquifers for both agricultural and urban uses.

By contrast, the Borough of Rocky Hill’s water worries seem quite small. But these concerns are being shared by more and more communities worldwide. And they have to do with a class of so-called “forever chemicals” known as PFAS. “Health studies have been done,” says Rocky Hill Mayor Robert “Bob” Uhrik. “ This is a health risk. These compounds are all over the place. Literally everywhere.”

The Rocky Hill Water Tower near the Route 518/206 intersection.

Rocky Hill has enough in its drinking water that the NJ Department of Environment Protection is requiring its water department — along with many other municipal water departments and companies in the state — to add an expensive remedy by January that is expected to hike up the cost of drinking water for residents.

Other local water systems in violation of the new standards include Hopewell Borough, PFAS—which stands for per-and polyfluoroalkyl substances —are a large family of thousands of manmade chemicals that have been used in industrial and commercial applications for more than 70 years.

Also known as forever chemicals, PFAS repel water and oil and are resistant to heat and chemical reactions. This quality has proven extremely valuable in a variety of products—stain-proof/waterproof garments (GORE-TEX) and furniture (Scotchgard), nonstick cookware (Teflon), leakproof food packaging, and fire suppression foams widely used at airports and factories.

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However, “these chemicals, which are long-lasting in the environment and accumulate in the human body over many years, can present health concerns for the public over time,” according to the NJ Department of Environmental Protection (NJDEP).

There are thousands of PFAS chemicals. Two of the worst are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). “Since human health effects are associated with even low-level exposures to PFOA and PFOS, it is important to minimize exposure from drinking water,” according to a fact sheet published by the NJ Department of Health. These were phased out of production in the United States.

The NJ DEP reports that PFOS can enter drinking water through industrial release to water, air, or soil; discharges from sewage treatment plants; land application of contaminated sludge; leaching from landfills; and use of certain firefighting foams.

It’s a mystery

Rocky Hill borough officials do not know how PFOS chemicals got into their drinking water. There is no PFOS “discharge source” in Rocky Hill, according to a comprehensive interactive map of suspected PFOS-discharging sites created by the non-profit Environmental Working Group (EWG).

This mystery demonstrates the extent of the problem. PFOS molecules are not only carried by waterflows, but even by the winds. Their resistance to normal biodegrading has allowed PFOS to build up in the environment, including the bodies of humans and animals.

How serious is the problem?

To begin with, four types of PFAS (including the more dangerous PFOS and PFOA) have been found in the blood of about 98 percent of the United States population, according to the NJ Department of Health (DOH). Still, there are real reasons for concern. PFOS are endocrine disrupting chemicals that can affect hormone systems. Those exposed to PFOS have a higher risk for high cholesterol, kidney cancer, testicular cancer, and damage to the immune system.

The health risks have led to dozens of lawsuits against companies like DuPont, which manufactured the chemicals. PFOS in a mother’s body can cross into a developing embryo, increasing risks of low birthweights and birth defects, according to “Environmental Health News.”

The Rocky Hill Borough Water Department just misses compliance of the new, strict DEP standards by 2.75 parts per trillion (ppt). In other words, it is almost three drops of PFOS in 35 junior size Olympic pools. This is nothing like the situation at the Camp LeJeune military base, which reported well water measures of 172,748 ppt of PFOS, sparking a class action lawsuit.

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To explain: The NJ DEP new standard for PFOS is 13 ppt. Rocky Hill’s municipal well water contains an average of 15.75 ppt – just 2.75 parts per trillion above the limit. But because PFOS don’t break down in water, the potential for their retention—and buildup—in human bodies over time can be serious. “It’s significant because it’s not a chemical we can break down,” says Catherine Plunkett, Rocky Hill Borough council member and chairperson of the Water, Sewer & Environment Committee.

The NJ DEP is serious about a remediation deadline looming at the end of November. If the PFOS remediation system isn’t up, running and effectively lowering the ppt below upper threshold, the borough faces fines. Plunkett says, “The biggest question we get is, ‘why is this taking so long?” In her view, it hasn’t taken long, given the amount of preparation to be done. And there were major choke points along the way.

Funding was a major initial priority, especially for a small borough whose population of some 700 people would be hard pressed to divide the early estimate of $1.5 million among them. Rocky Hill Borough engineer Rob Martucci has been deeply involved in the PFOS remediation. He alerted Rocky Hill to a U.S. Department of Agricultural $1.2 million combination grant and loan. The borough’s water committee prepared and submitted the USDA funding application. “We got the grant about 9 to 12 months after applying,” says Plunkett, “We literally got that grant in the nick of time.”

In turn, Mayor Uhrik credits Senator Cory Booker with helping Rocky Hill successfully apply for a separate $1.67 million federal grant, a special Congressional earmark to help with PFOS. It has a double value: In addition to completing funding for the remediation, a portion of the monies can be put toward paying off the state loan. But with these government grants come limitations. “The components must be 100 percent American-made,” Plunkett says. “We couldn’t use components from China. And if made of metal, [it] must be all steel.” She adds, “with COVID, the costs of all the metals went up.

So between COVID and all the rules and regulations, that’s why it took so long.” Rocky Hill borough officials have selected a vendor, and the remediation system is now being built, she says. “The system took about nine months to create.”

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By comparison, a previous Superfund site remediation at the defunct Princeton Gamma Tech site behind Wawa at the corner of routes 518 and 206 in Montgomery was easier. It involved volatile organic chemicals whose molecules readily break apart during aeration. As noted earlier, the PFOS molecules don’t break up during air or water exposure.

Rocky Hill’s new PFOS system will use sand-grain-sized resin beads, which are charged to attract and hold PFOS molecules. When the filters with their trapped PFOS molecules are removed, the only practical way to break the bonds between the atoms in these molecules, and thus neutralize the PFOS contaminants, is by incineration. (The vendor will also provide this service, Plunkett says.)

Retired scientist/engineer Ivor Taylor of Rocky Hill, who is credited with designing the aeration system that remedied the Trichloroethylene (TCE) problem in 1983, also recommended the solution to bring Rocky Hill’s PFOS issue to comply with the new NJ environmental standards. Through his Rocky Hill Water group, Taylor has advocated for the ion-exchange system similar to that employed successfully for PFOS remediation in Horsham, PA. Visit for more information on the system.

The PFOS remediation system is being installed at the water tower site, adjacent to the Princeton North Shopping Center. The equipment by the existing fieldstone pump house must be expanded, and the overall project is on schedule to be completed by the end of the year.

Borough council members express confidence the work will be completed on time and will be successful in removing PFOS. “I feel like so many people are passionate and proactive about this, and so things are getting done,” sums up Councilwoman Plunkett. “That’s why I am so thankful I live in Rocky Hill.”


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