1,4-Dioxane levels in Haw River have decreased following Nov. 3 slug from Greensboro


PITTSBORO — Town staff continues to be encouraged by the most recent results from water samples taken from the Haw River following the Nov. 3 1,4-Dioxane discharge from Greensboro.

Lab results from before Thanksgiving showed concentrations of 1,4-Dioxane decreasing from the Nov. 17 spike of over 80 parts per billion, which was more than double the EPA recommended threshold. Raw water samples from Nov. 18 and Nov. 19 showed 50.5 parts per billion and 34.1 parts per billion, respectively. Treated water at Pittsboro’s treatment plant, however, were above the EPA recommended threshold, with numbers showing 46.3 parts per billion and 49.8 parts per billion on Nov. 18 and Nov. 19.

And late Monday, Pittsboro Town Manager Chris Kennedy announced lab results from water samples drawn from the Haw River on Nov. 24 indicated levels as low as 6.58 parts per billion.

Kennedy said, however, elements of 1,4-Dioxane have still been able to trickle into the town’s water system and storage tanks, indicated by the still elevated numbers in those water samples. 1,4-Dioxane levels in the water storage tanks had decreased, he said, but were still elevated compared to the numbers in the Haw River.

Kennedy said it would take time for the 1,4-Dioxane to filter out.

“The improvements in the raw water quality will eventually result in improved concentration levels in the finished water circulated in our distribution system,” he said.

While town staff is hesitant to say Pittsboro has been cleared of more contamination from the Nov. 3 discharge, Kennedy said in an email that town staff are optimistic about the numbers.

“Staff is not considering us ‘out of the woods’ just yet, but we are relieved to see diminishing concentration levels,” he said.

Town staff will continue to test the water from the Haw River and storage tanks until staff are certain the contamination has passed, according to Kennedy.

The City of Greensboro recently agreed to new conditions on the agreement regarding the threshold allowed for 1,4-Dioxane discharges. (See accompanying story in this edition.) The new conditions have lowered the threshold allowed for Greensboro to discharge from 45 parts per billion to 35 parts per billion. The new agreement also increase fines on discharges that exceed the 35 parts per billion limit.

Town staff received a copy of new agreement on Monday morning, but by press time on Tuesday Kennedy hadn’t commented regarding it.

Reporter Taylor Heeden can be reached at theeden@chathamnr.com.