Horsham Water & Sewer Authority, April 2019

Since July 2014, the Horsham Water and Sewer Authority (HWSA) has been responding to the discovery of PFOS and PFOA in local groundwater, sourced from the nearby Naval Air Station Joint Reserve Base Willow Grove. In June 2016, HWSA shut down a total of 5 wells exceeding the May 2016 EPA health standard of 70 ng/L and set a goal of reducing PFOA and PFOS to non-detect (ND) level in all drinking water supplied. HSA began installing granular activated carbon (GAC) filters to remediate and return the 5 impacted wells to service. A pilot test evaluated the effectiveness of a newly developed PFAS-selective ion exchange resin placed downstream of the GAC filters on 1 well as a polishing step to obtain ND levels. After several months of operation, the GAC filters were bypassed and the resin continued to operate until the concentration of PFAS rose above the detection level. Upon full transition to a long-term plan by fall 2019, the public water supply will be sourced by 10 wells with PFAS removal filters installed, purchased water from a supplier with a PFAS removal filter installed, and purchased water from a second supplier that has PFAS at or around non-detect levels. https://www.horshamwater-sewer.com/pfas-summary More information https://www.wateronline.com/doc/polishing-pfas-to-non-detect-levels-using-pfas-selective-resin-0001 and https://www.wateronline.com/doc/pilot-study-ion-exchange-and-gac-to-reduce-pfas-to-non-detect-0001