Pittsboro hit with another dose of 1,4-dioxane from Greensboro
This story has been corrected. Greensboro told Policy Watch today that they do not believe Shamrock Environmental is the source of the contamination. The data provided by the City of Pittsboro did not take into account the dilution factors in Greensboro.
Pittsboro’s drinking water received another 1,4-dioxane hit last week, which the city attributes to an “additional build-up of contamination from Greensboro” on July 6, according to a press release released today. .
As reported by Policy Watch, on June 30, the city of Greensboro illegally released 1,4-dioxane levels 20 times higher than the EPA’s recommended levels from its TZ Osborne wastewater treatment plant into the creek. South Buffalo, a tributary of the Haw River, according to a press release from the NC Environmental Quality Department. Pittsboro gets its drinking water from the Haw River.
1,4-Dioxane is a toxic chemical used in degreasers that the EPA has classified as a probable carcinogen. There is no regulatory standard for 1,4-dioxane, but the EPA has set a health advisory target of 35 parts per billion for drinking water, which equates to an excess cancer risk of 1 in 10,000 lifetime. The target for surface water is more stringent, at 0.35 ppb, a lifetime excess cancer risk of 1 million in 1.
Test results announced by the City of Pittsboro show that on July 6, the levels of 1,4-dioxane in raw water – directly from the Haw River – ranged from 26.5 parts per billion to 93.6 ppb. Treated drinking water from two sources was also high: Chatham Forest, 66.8 ppb and Water Reservoir, 21.7 ppb. The treated water from the Horton Reservoir was 1.71 ppb.
These levels are higher than those of July 2 when the raw water contained 1,4-dioxane levels at 76.5 parts per billion and the treated drinking water had levels below 1.25 ppb.
Meanwhile, results of upstream environmental testing from Shamrock showed that its mixed effluent in the TZ Osborne wastewater treatment plan on July 6 and 8 reached 98.8 ppb. A “channel seizure” – before the Shamrock wastewater was mixed – measured 466 ppb.
However, City of Greensboro spokesperson Elijah Williams said Shamrock Environmental was not the source of the contamination. Considering the dilution factors, Shamrock levels should have been much higher for him to be responsible for this spill. Shamrock Environmental is in the waste management business, including tanker cleaning services. She was responsible for a previous spill in 2019, but Greensboro recently excluded the company from that incident.
Although 1,4-dioxane is extremely difficult to remove from drinking water using conventional treatments, the City of Pittsboro refreshes the water in its reservoirs with better quality finished water to dilute and remove. contamination.
The TZ Osborne Wastewater Treatment Plant in Greensboro receives effluent from residential and industrial customers in Guilford County.
Pittsboro officials said in a press release that recent rains, along with the flushing of the urban system, are helping to reduce levels of contamination. The city will continue sampling until 1,4-dioxane levels are not detected.
Pittsboro plans to release the results of its sampling until July 9 tomorrow.
In addition, the Environmental Management Commission is due to discuss 1,4-dioxane at its meeting tomorrow, which begins at 9 a.m.