Removal of PFAS Contamination in Horsham Township, PA Water Supply

In 2016, the Horsham Water and Sewer Authority (HWSA) had an ongoing effort to remove perfluoroalkyl substances (PFAS) contamination from local potable well water supplies in Bucks and Montgomery counties located in Pennsylvania, U.S.A.

It was believed that the contamination stemmed from firefighting foams used at Warminster Naval Air Warfare Center, Horsham Naval Air Station Joint Reserve Base, and Horsham Air Guard Station, which caused the shutdown of approximately 160 public and private water wells. Despite a federal health advisory for two prominent PFAS compounds, PFOA and PFAS at 70 ppt, pressure from the community, including local politicians, mandated that the water should have non-detect levels of PFAS from all wells. For HWSA to move forward they needed the right product, funding, and permitting.

After a full investigation to find the best approach, the HWSA Superintendent and their contract engineer, Gilmore Associates, identified a potential solution, Purolite’s pilot plant study with PFAS-selective ion exchange resin that assessed the cost and performance between resin technology and granular activated carbon (GAC). Purolite’s representatives met with the team and demonstrated the operating and capital expense cost-performance advantages by using Purofine PFA694E as a standalone treatment or polisher to GAC. As a result, HWSA suggested that Purolite install a polisher to the existing GAC system provided by Altair at their Well 10.

Next, HWSA needed to obtain permits from the Southeast Pennsylvania Department of Environmental Protection (DEP) to include using NSF/ANSI-61 certification, pilot results demonstrating performance and product approval for Purolite's PFA694E.

Finally, the funding was secured, and the plan was in motion. HWSA received a grant from Pennsylvania DEP to remove PFAS contamination at Wells 10, 17, and 21, and temporarily installed GAC treatment systems until a long-term solution could be put in place. The grant stipulated that the plant would need ongoing PFAS sampling to ensure both GAC and ion exchange performance.

Purolite's role in this project was to bring the water to a non-detectible level of PFAS by using their ion exchange resin as a polisher to the GAC system on their Well 10.

After a successful pilot using resin filtration as an addition to GAC, the HWSA was able to return to full service and supply treated water to the public water system. The monitoring of full bed exhaustion would continue to determine the total performance of the resin. As a precaution, if detection was observed then the flow would be re-directed to their waste treatment plant.

To date, HWSA has been able to maintain non-detectable PFAS levels. Purolite developed the ion exchange resin treatment that resolved HWSA's PFAS contaminated water supplies through cutting edge technology -- and offered a cost-effective alternative to GAC for PFAS remediation.

With the success of Well 10, Horsham is now pursuing lead-lag resin only treatment for Well 10 as well as Wells 17 and 21.