The possibility that coal tar – a toxic byproduct of early gas production – may have migrated off a state Superfund site in the City of Tonawanda into a nearby residential neighborhood is causing concern among city officials and residents.
Carney Street resident Linda Freer describes a “terrible, wrenching smell” when she steps outside in the early morning and says other residents report a coal tar smell backing up into their homes via the sewers.
Worries began about six months ago, when a sanitary sewer line break on Carney in the city’s Gastown section resulted in a sinkhole. At that time, city public works crews inserted a camera in the sewer at Carney and East Niagara Street to investigate the break and when it was retrieved, the underside of the camera and attached line were coated in an oily substance.
But there was not enough residue for a lab to analyze the substance to confirm if it was coal tar, according to the state Department of Environmental Conservation.
Mayor Rick Davis keeps a sample of the substance in a jar in his office and says he wants National Fuel, which is responsible for cleanup of the former Gastown manufactured gas plant, and the contractor, GEI, to also remediate any sewer contaminated with hazardous material.
“I want to see them replace all the contaminated sewer line, get the contaminated sewer line out of there,” he said. “In order to do that they’re going to have to dig up East Niagara from where the contamination starts to where it ends and repave it. And I would like that done sooner rather than later.”
The source of the contamination is a 3.5-acre triangular site on East Niagara, between Carney and East Avenue.
Tonawanda Gas Light Co. opened there in 1884, producing gas first through a process known as coal carbonization and, later, carburetted water. In 1923, the facilities were dismantled, although several structures remained underground.
Coal tar first turned up in the sump of Gastown Sportsmen’s Club in 1993.
Cleanup at the site began earlier this year and calls for temporary relocation of businesses, excavation of contaminated areas to a depth of six feet and permanent immobilization of deeper contamination using solidification.
In addition, plans call for construction of three underground collection trenches, removal of the foundation of the one remaining gas holder and dredging sediment along the south shore of Tonawanda Creek, just east of a railroad bridge, over an area approximately 80 by 160 feet, among other actions.
“Right now they’re over there dredging the canal to get the coal tar that leached into the canal out of there,” Davis said.
Freer said she worries that coal tar carried northward by groundwater toward the canal has affected fish and wildlife.
“They might be catching it now, but how long has it been leaking?” she said. “We don’t know how long it’s been seeping into the canal.”
Meanwhile, the Carney sewer break and sinkhole were repaired on Dec. 11 and 12 by a DEC contractor, OpTech, which was brought in at the city’s request and has training in the safe excavation and disposal of potentially hazardous soil.
No coal tar was seen or smelled by workers or detected by an on-site monitoring device during the sewer repair work, according to the DEC. The contractor dug to a depth of 11 feet, two feet deeper than the sewer line, to confirm the absence of coal tar, DEC officials said.
Soil samples were sent to a lab for analysis, and the DEC expects results back as early as this week. The DEC expects results to confirm that coal tar was not present in the area of the sewer break.
But that hasn’t assured residents like Freer, who are left with a lot of questions.
“I’m concerned because I don’t know what’s in the soil,” she said. “Now that they say it’s not coal tar, what is it then? We, the residents, don’t know.”
The DEC does not yet know what the oily substance on the camera was, but said it may have been a weathered diesel or fuel oil, which can have a similar odor under certain conditions.
Davis said he remains convinced that coal tar has infiltrated the sewers and is adamant that the sewers on East Niagara be replaced as part of the cleanup. Under a consent order between the city and the DEC, the city is borrowing millions of dollars to replace sewers throughout the city due to storm sewer overflows during heavy rain.
“The DEC is going to hold us to a hard deadline when it comes to this mandated work we have to do, but yet they’re not going to hold National Fuel and GEI to that same standard,” Davis said. “I mean, who are they working for?”
It’s a quality-of-life and health and safety issue for residents, he said.
“Every time we clean out the sewers in that area as part of routine maintenance, or there’s a heavy rain event, residents get the smell of coal tar backing up their sanitary sewer laterals coming into their house,” he said.
“It can get extremely nauseous at times when you’re trying to live there to smell this.”