State regulators this week said they plan to begin testing groundwater from monitoring wells in New Hanover County for the presence of PFAS compounds.
Officials and staff from New Hanover County, the City of Wilmington, and Cape Fear Public Utility Authority discussed PFAS affecting groundwater in the County during a conference call Thursday with representatives from the North Carolina Department of Environmental Quality (NCDEQ).
This action came after CFPUA staff presented results of recent testing of its wells to NCDEQ. Results of CFPUA’s testing included detections of PFAS compounds in six of 25 wells that provide water to the Richardson Water Treatment Plant.
PFAS compounds found only downstream from the Chemours’ chemical plant near Fayetteville constitute much of the PFAS detected in these wells, in most cases making up more than 90 percent. Total PFAS levels in those wells ranged from 25 parts per trillion (ppt) to 65 ppt.
Richardson, the second-largest of CFPUA’s three drinking water-distribution systems, serves customers in northern New Hanover County, including Murrayville, Wrightsboro, Porters Neck, and parts of Castle Hayne and Ogden.
Recent tests show Richardson continues to be effective at filtering PFAS compounds. No PFAS were detected in finished drinking water sampled in March, while a trace amount – 0.6 parts per trillion (ppt) – was detected in a sample taken April 16.
Richardson WTP is sometimes referred to as the Nano Plant because it contains state-of-the-art membrane technology recognized as one of the best available filter options. Its source is groundwater drawn from wells tapping the Castle Hayne and Peedee aquifers.
As with similar membrane-based filters, constituents removed during Richardson’s treatment processes end up in a side stream, typically called “concentrate.” Concentrate sampled April 16 had total PFAS concentrations of 60.9 ppt.
The concentrate is piped to a discharge point into the Intracoastal Waterway. Results from testing of the concentrate have been shared with NCDEQ staff