Pittsboro officials: “the Town was simply lucky this time” regarding 1,4-Dioxane from Greensboro

The Haw River, as viewed from the Bynum bridge (File photo: Lisa Sorg)

The slug of toxic 1,4-Dioxane coursing down the Haw River from Greensboro arrived in Pittsboro at just the right time.

Pittsboro Town Manager Chris Kennedy announced in a press release today that based on low levels of compound in drinking water, the contamination passed the town’s water intake from the Haw River during “dormant raw water draw hours,” when demand is low, as common in fall and winter.

Levels of 1,4-Dioxane in both treated and untreated water in Pittsboro ranged from less than 1 part per billion to 2.09 ppb. The EPA has set a health advisory goal of 35 ppb in drinking water, which represents a 1-in-10,000 excess lifetime cancer risk.

That is not as protective as the 1-in-1 million cancer risk that the EPA uses for chemicals that have no safe dose. However, research is incomplete on 1,4-Dioxane, and the EPA has yet to set legally enforceable standards for the compound.

1,4-Dioxane is a toxic chemical used in degreasers that the EPA has classified as a likely carcinogen.

Routine sampling showed Greensboro’s TZ Osborne wastewater treatment plant discharged the contamination on Wednesday, Nov. 3, but the city did not receive the lab results until Monday, Nov. 8, at 11:20 a.m.

Kennedy said that Greensboro notified them about three hours later. The amount of 1,4-Dioxane in the original discharge was 767 parts per billion; that’s more than 2,100 times the EPA’s and the state’s health advisory goal for surface water. That level is more stringent — just 0.35 ppb — than in drinking water.

If Pittsboro’s raw water intake had pulled the contamination into the drinking water system, which has happened before, the contamination would have “persisted in our system for weeks,” Kennedy said. “While this news is a relief, it does not discount the fact that an excessive release could have contaminated our drinking water supply. Frankly, the town was simply lucky this time.”

Kennedy said the town will continue to sample both treated and untreated water “until it is abundantly clear that the 1,4-Dioxane has cleared the raw water intake.”

Greensboro has yet to publicly announce the source of the contamination.

The wastewater treatment plant in Greensboro receives discharges from both residential and industrial customers in Guilford County. From there, the plant treats the discharge before sending it into South Buffalo Creek, which feeds the Haw. However, conventional treatment systems don’t remove 1,4-Dioxane.

The discharge violates the terms of a  Special Order by Consent between DEQ and the City of Greensboro, which set a maximum daily level of 45 parts per billion of 1,4-Dioxane in wastewater. The Haw River Assembly, represented by the Southern Environmental Law Center, has challenged the terms of the order, saying they are not protective enough.

The recent incident was just one of several illegal discharges from the Greensboro plant. In July 2021, sampling results showed that levels from in wastewater ranged from 543 parts per billion to 687 parts per billion. Greensboro officials said they had not identified the source.

In August 2019, Greensboro’s discharge contained levels of 1,4-Dioxane ranging from 705 ppb to 1,210 ppb. The source of the contamination was Shamrock Environmental, an industrial customer that discharges its wastewater to the Osborne plant. That incident prompted DEQ to enter a Special Order by Consent with the city.

While DEQ regulates discharge from cities and towns, the municipalities are responsible for regulating their dischargers and ensuring wastewater is compliant with state and federal law.

According to Greensboro documents obtained under public records law, roughly two dozen companies discharge their wastewater into the city system. Since 2018, the city has issued 18 violations related to contaminants in the discharge, none of them related to 1,4-Dioxane.

Shamrock Environmental has been cited three times and fined $2,500 for exceedances of a compound called p-cresol, which is used in the manufacture of household products. Shamrock is not a manufacturer, but is a hauler and disposal service for that sector. Vertellus, a specialty chemical company received violations for exceedances of chloroform, toluene and since.

Greensboro releases yet another slug of 1,4-Dioxane into Haw River, Pittsboro’s drinking water supply

Update Nov. 10, 9:30 a.m.: Cory Saulsbury, superintendent of Pittsboro’s water plant told Policy Watch that sampling from from Nov. 3 to Nov. 8 showed levels of 1, 4-Dioxane at 1.07 ppb. Saulsbury said the town will “continue to monitor the situation by pulling samples every day this week with a rush order.” 

Greensboro’s wastewater treatment plant illegally discharged high levels of the likely carcinogen 1,4-Dioxane into the Haw River, the drinking water supply for the Town of Pittsboro and other downstream communities along the Cape Fear River.

Adam Pickett, Pittsboro’s public utilities director, confirmed to Policy Watch that there had been a discharge. Emails obtained by Policy Watch show that the discharge occurred on Nov. 3, and Greensboro notified downstream communities, including Pittsboro, on Nov. 8. The amount of 1,4-Dioxane in the original discharge was 767 parts per billion; that’s more than 2,100 times the EPA’s and the state’s health advisory goal for surface water.

The discharge violates the terms of a  Special Order by Consent between DEQ and the City of Greensboro, which set a maximum daily level of 45 parts per billion of 1,4-Dioxane in wastewater. The Haw River Assembly, represented by the Southern Environmental Law Center, has challenged the terms of the order, saying they are not protective enough. Haw Riverkeeper Emily Sutton told Policy Watch that Greensboro had not contacted the group directly about the latest discharge, “even as negotiations are underway regarding the Special Order by Consent triggered by major 1,4- dioxane releases” that occurred in 2019 and 2021.

1,4-Dioxane is a toxic chemical used in degreasers that the EPA has classified as a likely carcinogen. There is no regulatory standard for 1,4-Dioxane, but the EPA has set a health advisory goal of 35 parts per billion for drinking water, which equals a 1-in-10,000 lifetime excess cancer risk. The surface water goal is more stringent, at 0.35 ppb, a 1-in-1 million lifetime excess cancer risk.

Emails show that Pittsboro’s latest sampling through Nov. 2 showed levels of 4 parts per billion. It’s still unknown how much 1,4-Dioxane entered the town’s drinking water, but results should be available this afternoon.

Elijah Williams, water reclamation manager for the City of Greensboro, told Policy Watch that utilities staff has notified the NC Department of Environmental Quality (NCDEQ) and downstream utilities and is actively investigating possible sources of the substance.

This is just one of several illegal discharges from the Greensboro plant. The most recent one occurred in July 2021; sampling results showed that levels from in wastewater ranged from 543 parts per billion to 687 parts per billion. Greensboro officials said they had not identified the source.

In August 2019, Greensboro’s discharge contained levels of 1,4-Dioxane ranging from 705 ppb to 1,210 ppb. The source of the contamination was Shamrock Environmental, an industrial customer that discharges its wastewater to the Osborne plant.

The TZ Osborne Wastewater Treatment Plant in Greensboro receives discharges from both residential and industrial customers in Guilford County. From there, the plant treats the discharge before sending it into South Buffalo Creek, which feeds the Haw. However, conventional treatment systems don’t remove 1,4-Dioxane.

 

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 Town of Pittsboro did not account for dilution factors in Greensboro.

Pittsboro’s drinking water took another hit of 1,4-Dioxane last week, which the town attributes to an “additional slug of contamination coming from Greensboro” on July 6, according to a press release today.

As Policy Watch reported, on June 30, the City of Greensboro illegally discharged levels of of 1,4-Dioxane 20 times higher than EPA recommended levels from its TZ Osborne wastewater treatment plant into the South Buffalo Creek, a tributary of the Haw River, according to a NC Department of Environmental Quality press release. Pittsboro sources its drinking water from the Haw River.

1,4-Dioxane is a toxic chemical used in degreasers that the EPA has classified as a likely carcinogen. There is no regulatory standard for 1,4-Dioxane, but the EPA has set a health advisory goal of 35 parts per billion for drinking water, which equals a 1-in-10,000 lifetime excess cancer risk. The surface water goal is more stringent, at 0.35 ppb, a 1-in-1 million lifetime excess cancer risk.

Testing results announced by the Town of Pittsboro show that on July 6, levels of 1,4-Dioxane in raw water — straight from the Haw River — ranged from 26.5 parts per billion to 93.6 ppb. Treated drinking water at two sources were also elevated: Chatham Forest, 66.8 ppb and the water tank, 21. 7 ppb. Treated water from the Horton tank was 1.71 ppb.

These levels are above those on July 2 when raw water contained levels of 1,4-Dioxane at 76.5 parts per billion and treated drinking water showed levels of less than 1.25 ppb.

Meanwhile, upstream Shamrock Environmental test results showed that its mixed effluent into the TZ Osborne wastewater treatment plan on July 6 and 8  reached 98.8 ppb. A “flume grab” — before Shamrock’s wastewater had been mixed — measured 466 ppb.

However, City of Greensboro spokesman Elijah Williams said Shamrock Environmental is not the source of the contamination. Accounting for dilution factors, Shamrock’s levels would need to have been much higher for it to be responsible for this spill.  Shamrock Environmental is in the waste management business, including tanker cleaning services. It was responsible for a previous spill in 2019, but Greensboro has recently ruled out the company in this incident.

Although 1,4-Dioxane is extremely difficult to remove from drinking water using conventional treatments, the Town of Pittsboro is refreshing water in their stored tanks with better-quality finished water to dilute and flush the contamination.

The TZ Osborne Wastewater Treatment Plant in Greensboro receives effluent from both residential and industrial customers in Guilford County.

Pittsboro officials in a press release said that recent rainfalls, along with flushing the town system, is helping to reduce contamination levels. The town will continue sampling until the levels of 1,4-Dioxane are not detected.

Pittsboro expects to release results of its sampling through July 9 tomorrow.

Also, the Environmental Management Commission is scheduled to discuss 1,4-Dioxane at its meeting tomorrow, which begins at 9 a.m.

Pittsboro announces drinking water results after 1,4-Dioxane spill in Greensboro

The Haw River, as viewed from the Bynum bridge (File photo: Lisa Sorg)

Levels of 1,4-Dioxane in finished, or treated, drinking water in Pittsboro are below the EPA and North Carolina’s drinking water health advisory level, but much higher than stricter advisory goals for surface water.

The Town of Pittsboro released the results today, based on sampling from July 1 through July 6, shortly after Greensboro illegally discharged the toxic compound from its TZ Osborne wastewater treatment plant on June 30. The source of the 1,4-Dioxane has not been publicly disclosed, but state documents show that the City of Greensboro has required additional sampling from one of its industrial customers, Shamrock Environmental.

Treated drinking water levels in Pittsboro ranged from 1.06 parts per billion to 5.56 ppb. The highest level was detected on July 6 at the Chatham Forest tank.

The EPA health advisory goal for 1,4-Dioxane in drinking water is 35 ppb, which represents a 1 in 10,000 lifetime excess cancer risk.

The drinking water goal is controversial because the EPA recommendation for 1,4-Dioxane in surface water is more stringent — 0.35 parts per billion. That represents a
1 in 1 million lifetime excess cancer risk for humans, which the scientific community considers “acceptable.”

If the EPA and North Carolina’s drinking water recommendation for 1,4-Dioxane were as rigorous as that of the surface water, Pittsboro’s levels would be three to 15 times above the guidelines.

Six states have enacted stricter guidelines for 1,4-Dioxane in drinking water than North Carolina, all of them below 1 ppb: Colorado, California, Massachusetts, New Hampshire, New Jersey and Washington.

The raw water taken from the intake along the Haw River showed that on July 1, levels of 1,4-Dioxane were not detected. But on July 2, two days after the Greensboro release, concentrations in the Haw River hit 76.5 parts per billion. Levels decreased to 2.46 ppb on July 3, possibly because it had rained, before rebounding to 43.7 ppb by July 5.

These concentrations are seven to 200 times the EPA guidelines for surface water.

Pittsboro town staff will continue sampling until the results show non-detections “for an extended period,” according to a press release from Town Manager Chris Kennedy.

1,4-dioxane is toxic to people, causing liver and kidney damage, and increases the risk of cancer. It is used, and created as a byproduct, when manufacturing chemicals, paints, cosmetics, cleaning products, dyes, textiles, paper, and other products.

Below is a screenshot of the press release with the results and sampling points.

Greensboro violates consent order, discharges high levels of 1,4-Dioxane, heading toward Pittsboro, Fayetteville

South Buffalo Creek receives wastewater from Greensboro’s TZ Osborne treatment plant. The creek flows into the Haw River, a drinking water supply for the Town of Pittsboro. In turn, the Haw empties into Jordan Lake, which feeds the Cape Fear River. (Photo: Lisa Sorg)

This is a developing story and will be updated.

The City of Greensboro has discharged levels of of 1,4-Dioxane 20 times higher than EPA recommended levels into the South Buffalo Creek, a tributary of the Haw River, according to a NC Department of Environmental Quality press release. The contaminated discharge came from the city’s TZ Osborne Wastewater Treatment Plant; the source of the contamination has not been disclosed.

Preliminary sampling results show that levels of the likely carcinogen ranged from 543 parts per billion to 687 parts per billion in the wastewater. The EPA’s drinking water health advisory level is 35 parts per billion; in surface water the level is 0.35 parts per billion.

DEQ has notified Pittsboro and Fayetteville, both downstream from Greensboro, that their drinking water could become contaminated. Pittsboro could be affected as early as tomorrow, and based on the levels in the discharge, DEQ said the town’s drinking water could exceed the health advisory level.

Greensboro reported sampling results to the North Carolina Division of Water Resources this afternoon. Additional sampling is underway at the Pittsboro raw water intake.

EPA has identified 1,4 dioxane as a likely human carcinogen. 1,4 dioxane is a clear liquid that is highly miscible in water. It has historically been used as a solvent stabilizer and is currently used for a wide variety of industrial purposes. It is difficult, if not impossible to completely remove from drinking water using traditional treatment methods.

These concentrations violate a Special Order by Consent between DEQ and the City of Greensboro, which set a maximum daily level of 45 parts per billion. In a notice on the city’s website, Greensboro said it is actively investigating possible sources of the substance. This discharge does not affect Greensboro’s drinking water quality.

The Special Order by Consent was triggered by an event nearly two years ago, when discharge from the city’s TZ Osborne plant contained levels of 1,4-Dioxane ranging from 705 ppb to 1,210 ppb. The source of the contamination was Shamrock Environmental, an industrial customer that discharges its wastewater to the Osborne plant.

Shamrock is headquartered in Browns Summit; it has several facilities in North Carolina and one in Virginia. The Patton Avenue plant, responsible for the discharge, is a tanker cleaning facility. It also treats and manages wastewater, recycles and disposes of drilling mud, and hauls waste.

At the time, Greensboro did not notify state environmental regulators for nearly a month, when the city’s next report was due. The consent agreement requires Greensboro to notify DEQ within 24 hours if there are detections greater than 45 ppb.

Haw Riverkeeper Emily Sutton told Policy Watch that “this new release of 1,4-Dioxane in the Haw is a result of weak enforcement of the water quality standards. The EPA has stated that levels of 0.35 ppb over a lifetime is harmful to human health. The proposed special order by consent is a result of previous violations, but is proposed to allow 33-45 ppb to be discharged into the Haw watershed and transported to downstream communities. This is unacceptable. We have to stop these discharges at the source.”