DEQ Transparency Questioned About Naming 1,4-Dioxane Discharger

On Monday, October 14, 2019, North Carolina Health News reported that a release of 1,4-dioxane occurred earlier this year in Greensboro that sent elevated levels of the contaminant downstream to the Haw River and into Jordan Lake eventually traveling to the Cape Fear River. The report also stated that the North Carolina Department of Environmental Quality (DEQ) and Greensboro officials would not identify an industry source because it was a mistake that happened in early August and the company was cooperating with the City of Greensboro. A Greensboro water official said the company has been working voluntarily and proactively with the city for several years to curtail the release of 1,4-dioxane into surface waters.

The next day, Tuesday, October 15, 2019, DEQ posted a news release about the discharge naming the source as Shamrock Environmental Corporation. According to the news release, the City of Greensboro had not previously told DEQ the company's name. Although Shamrock was the source of the release, Greensboro holds the discharge permit for the pretreatment program. DEQ is pursuing appropriate enforcement for all identified permit violations.

The City of Greensboro took water samples on August 7 and received results two weeks later that showed 1,4-dioxane levels of 957 parts per billion (ppb). The EPA Cancer Risk value for surface water is 0.35 ppb. EPA's health advisory for drinking water is 35 ppb. On August 23, 2019, the Town of Pittsboro observed a temporary spike of  1,4-dioxane at levels of 107 ppb in their treated drinking water. The contamination made its way downstream to Fayetteville and Wilmington, where it was detected at elevated levels.

Wilmington has one of only a few utilities in the state with a filtration system capable of removing 1,4 dioxane. For most municipalities, the level going into their water treatment plants is close to the level going back out.