CARY, N.C. — Sometimes it’s helpful to take a step back and look at the big picture.
Cadillac and surrounding communities have been hyper-focused on the question of how to deal with PFAS contamination in the groundwater, perhaps without realizing that insight may be gleaned from other communities across the U.S. that have dealt with the same problem.
In Cary, North Carolina, PFAS first was detected in the municipal drinking water supply in 2015.
Betsy Drake, Cary’s water utility engineering manager, told the Cadillac News the system serves around 300,000 people, including residents of Cary, the town of Apex, and three major research universities nearby.
Initial testing detected low amounts of PFAS in the water but subsequent research conducted by a scientist at one of the local universities brought to light that the level of contamination was actually much higher.
Drake said the level of contamination uncovered in their municipal drinking water supply was comparable to elevated levels found in private wells in this area.
Unlike Cadillac, which gets its municipal water from the ground, Cary supplies its customers from the surface waters of Jordan Lake, primarily.
Another way that Cadillac is different than Cary is that PFAS has never been detected in the municipal water supply here but only in private drinking water wells.
Neighboring Haring Township, however, is in a similar situation as Cary because PFAS has been detected in its municipal drinking water supply.
Drake said she has not seen any data about the level of contamination in private wells around Cary, which is not too surprising; officials with the Michigan PFAS Action Response Team have said that Cadillac is unique in its level of community involvement, which has included a grassroots self-testing campaign.
Cary is similar to Cadillac, however, in that they don’t know exactly where the PFAS is coming from.
“We don’t have a smoking gun, so to speak,” Drake said. “It’s just pervasive in the environment.”
When Cary officials learned about the extent of contamination in the municipal water, Drake said they made a decision to develop their own testing and treatment strategy.
“It was something people were very interested in,” Drake said. “Drinking water is important to people.”
For years, Cary used powdered activated carbon on an as-needed basis to improve the taste and odor of the drinking water drawn from Jordan Lake.
Coincidentally, powdered activated carbon also is effective in removing PFAS from the water, so instead of using it intermittently, Drake said around 2017-2018 they made the decision to use it all the time.
North Carolina does not have statewide standards for PFAS contamination in drinking water, so they technically didn’t have to do anything when they found out about it, but Drake said they wanted to take a proactive approach to ensure the water is safe to consume.
Drake said they took the same approach to releasing data and information to the public, including creating an “emerging contaminants” section on the city website.
“Everyone can see what we’re doing about it,” said Drake, who added that she feels like there is more community trust in Cary than in many other cities that have been dealing with PFAS, in part because of their commitment to transparency.
The powdered activated carbon is effective in bringing PFAS levels to under 4 parts per trillion for the most harmful compounds. While North Carolina currently doesn’t have its own PFAS standards, Cary’s treatment strategy makes its water supply compliant with new federal standards announced in 2024.
Overall PFAS levels in Jordon Lake also have declined since awareness about PFAS contamination has increased, Drake said. While they don’t know exactly why levels are lower, Drake theorized that it might be due to industrial users downstream using less of the chemicals in recent years.
In addition to the powdered activated carbon, Cary also uses PFAS destruction technology to treat the drinking water as part of a pilot project.
The Cadillac News previously spoke to representatives of a company called Invicta Water for an article about destruction technologies. Invicta Water is based out of North Carolina and is part of the Cary pilot project.
Drake said they are interested in destruction technology for a couple of reasons.
For one thing, carbon doesn’t destroy the PFAS but merely collects it and turns it into a different form. Destruction technology systems developed by Invicta and other companies directly eliminate the chemicals in the water supply, with no need to transport the collected PFAS elsewhere for disposal.
Incorporating destruction technology into their process may reduce or eliminate the cost associated with disposing of the PFAS collected by the carbon, Drake said.
Another reason Cary officials decided to partner with Invicta on the pilot project is to support a “home-grown” company that is working on solutions to the PFAS problem.
“That was really appealing to us,” Drake said.
Destruction technologies also have the potential to more effectively remove some of the newer PFAS compounds that have shorter molecular chains than the older ones.
While the older, long-chain compounds such as PFOS and PFOA are among the most concerning from a public health perspective, removal of short-chain PFAS could become more of a priority as a result of their increased use in industry and in commercial products.
Traditional PFAS-removal technologies like carbon aren’t as effective at removing short-chain compounds.
“We find that our (powdered activated carbon) generally does very well with the long chains,” Drake said. “For the shorter chain compounds, it really depends on the specific compound.”
Drake added, however, that among the various types of carbon treatments, powdered activated carbon performs relatively well in removing many of the short-chain compounds.
Cary should be getting data back from the Invicta pilot project this fall, Drake said.
In Cadillac, Local Development Finance Authority board member Brian Warner has been spearheading efforts to bring a similar pilot project here.
The LDFA was formed in the 1990s to fund and oversee the removal of contaminants in the Cadillac industrial park. The LDFA system wasn’t designed to address PFAS but has been in the process of adapting to the emerging contaminant in recent months.
Warner has proposed treating one of the LDFA wells using destruction technology to find out if such a system would be a good fit for Cadillac in the future.
Keep reading the Cadillac News for updates on this project as they become available.
Story Highlights • The town of Cary, North Carolina for years has been dealing with PFAS contamination in its municipal water supply. • The Cadillac News spoke with Cary’s water utility engineering manager to learn about the town’s PFAS history and what it has done to address the contamination.