WILMINGTON, N.C. (WECT) - The N.C. Department of Environmental Quality is notifying drinking water facilities on the Cape Fear of high levels of 1,4-dioxane discovered in Reidsville.
State officials said in a news release that samples received on Tuesday showed 1400 ug/L (micrograms per liter) of 1,4-dioxane from the Reidsville wastewater treatment plant on October 11, 2019. The EPA has set an advisory lifetime health goal of 35 ug/L for drinking water.
Reidsville officials say two companies within their pretreatment system, DyStar and Unifi, are possible sources of the chemical.
The samples collected at the Reidsville plant are part of a formal investigation launched earlier this month by DEQ into 1,4-dioxane detected in the Cape Fear River Basin when the city of Greensboro reported the chemical was released in August by Shamrock Environmental Corporation from a processing facility in Greensboro’s Bryan Park Industrial Complex.
DEQ stated in the Tuesday news release that they alerted downstream utilities of the elevated 1,4-dioxane levels, and instituted weekly sampling at the Reidsville site. Results from the weekly sampling already required at the Greensboro site as a result of the August 1,4-dioxane investigation show 20 ug/L on October 7 and 45 ug/L on October 11.
“Weekly sampling will help determine the extent of the loading to the river. DEQ will pursue appropriate enforcement action for all identified permit violations in this case,” the release from the DEQ stated.
In a news release Wednesday morning, CFPUA confirmed they were alerted Tuesday evening about the elevated levels of 1,4-dioxane, stating “NCDEQ is investigating the discharges, including their potential dilutions and effects on concentrations downstream. CFPUA staff anticipate significant dilution of the discharge by the time it reached the raw water intake on the Cape Fear River near Lock & Dam No. 1.”
CFPUA added that its Sweeny Water Treatment Plant, which treats water from the Cape Fear River, is among a few plants in the state that can effectively filter 1,4-dioxane.
“Sweeney typically removes about 67 percent of 1,4-dioxane in raw (untreated) river water,” CFPUA officials stated in a news release.
CFPUA says it and other utilities have been in communication with state regulators regarding 1,4-dioxane and that CFPUA regularly monitors raw and finished water for the chemical.
New Hanover County has seen several spikes in 1,4-dioxane levels recently. In September, The Cape Fear Public Utility Authority (CFPUA) asked for assistance from the DEQ after a fourth increase in 1,4-dioxane levels this year.
The EPA says 1,4-dioxane is a likely human carcinogen and has been found in groundwater across the nation. The synthetic industrial chemical is highly mobile and does not readily biodegrade in the environment.