PFAS Removal and Phased Construction of Existing Treatment Facility
Weston & Sampson helped the City of Portsmouth, New Hampshire, address the impacts of PFAS in the drinking water supply at the former Pease Air Force Base, listed on the US EPA’s National Priorities List (NPL). Our interdisciplinary team of engineers, scientists, and construction specialists designed and installed temporary granular activated carbon (GAC) treatment to remove lower concentration PFAS levels. We then designed upgrades to the existing treatment facility, including 3,800 square feet of space to house ion exchange resin and GAC filters, along with a new control room and supervisory control and data acquisition (SCADA) system. Other system appurtenances include a raw water booster pump skid, chemical feed systems, a backwash water recycle system, HVAC, plumbing, and an emergency generator. Additional improvements include refurbishment of well stations with new instrumentation, new vertical turbine well pumps, and variable frequency drives. The new permanent treatment system is designed to treat 1,200 gpm from three wells. Construction was carefully phased over two years to maintain system operation and minimize shutdowns.