The Orange County Water District (OCWD) and the Yorba Linda Water District (YLWD) has began operating what is dubbed the US largest ion exchange (IX) treatment plant to remove per- and polyfluoroalkyl substances (PFAS) from local well water.
PFAS are a group of thousands of manmade, heat-resistant chemicals that are prevalent in the environment and are commonly used in consumer products to repel water, grease, and oil. Due to their prolonged use, PFAS are being detected in water sources throughout the US, including the Orange County Groundwater Basin, which supplies 77% of the water supply to 2.5 million people in north and central Orange County. Despite playing no role in releasing PFAS into the environment, water providers must find ways to remove it from their local water supplies.
Steve Sheldon, president of OCWD, commented: “We worked closely with YLWD to rapidly construct this treatment facility to remove PFAS from groundwater and ensure that they continue to meet all state and federal drinking water standards.”
YLWD, one of 19 water providers that pump water from the groundwater basin, has all 10 of its groundwater wells impacted by perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), prompting it to temporarily shut down wells and transition to purchasing imported water sourced from the Colorado River and Northern California. These wells were among dozens of wells throughout Orange County that were removed from service in 2020 after the state of compounds no longer produced in the US.
Located at the existing YLWD headquarters in Placentia, the PFAS Treatment Plant uses an IX treatment system made of highly porous resin that acts like magnets that adsorb and hold onto contaminants. It consists of 11 IX systems, a 25 MGD booster pump station and an upgraded onsite chlorine generation system. During treatment, contaminants such as PFAS are removed from the water before it goes into the distribution system. Construction began in March this year, and the facility will be capable of treating up to 25 million gallons per day. Phil Hawkins, president of YLWD, said: “Bringing this treatment facility online is very important for our customers. It means YLWD can safely increase its use of local groundwater, which is less expensive and more reliable than imported water.”