The North Carolina Department of Environmental Quality’s Division of Water Resources (DWR) has been alerted to elevated levels of 1,4-dioxane discharged from the City of Asheboro Wastewater Treatment Plant (WWTP) into Hasketts Creek. This creek flows into the Deep River within the Cape Fear River Basin.
The Environmental Protection Agency (EPA) classifies 1,4-dioxane as a “likely human carcinogen,” meaning it is a substance that likely can cause cancer. The chemical is used for various industrial purposes.
On May 3, after receiving the report from Asheboro WWTP regarding the elevated levels of 1,4-dioxane, DWR staff informed downstream drinking water utilities. These included the City of Sanford, Fayetteville Public Works Commission, Brunswick County, and the Cape Fear Public Utility Authority in Wilmington.
The concentration detected by Asheboro WWTP was 826 parts per billion (ppb), collected on April 25. On the same day, DWR found a concentration of 730 ppb in their sample from Asheboro WWTP’s discharge. According to DEQ’s calculations using EPA toxicity data for lifetime exposure, an average monthly concentration protective of downstream water supplies should be about 22 ppb for this discharge.
These concentrations were determined through “grab samples,” which are wastewater samples taken at a single point in time by both the facility and DWR. The testing method used is certified by the U.S. Environmental Protection Agency.
Monitoring efforts are also ongoing at other wastewater treatment plants known to have 1,4-dioxane in their discharge into the Cape Fear River Basin. These include facilities in Burlington, Greensboro, High Point, and Reidsville.
Sampling data has been made available online under “Cape Fear River Basin 1,4-Dioxane Wastewater Discharge Data.”
