Small amounts of petroleum coming out of the ground in multiple locations in the area of Perrolee Street and flowing into Town Creek are believed to have come from a gas station on East Main Street in Gallatin, according to city and state officials who say the leak could have happened decades ago.
Based on currently available data from dye tracing and laboratory analysis, the leak appears to have originated from the gas station at the corner of East Main Street and Hartsville Pike, according to Kim Schofinski, deputy communications director for the Tennessee Department of Environment and Conservation (TDEC).
To date, at least eight known seep locations have been identified where the chemical is coming out of the ground including properties along Barton Avenue and a section of the nearby greenway.
“This is a significant amount of gas probably released over a long period of time,” Gallatin Stormwater Utility Manager Lance Wagner said about the leak. “It would take a pretty good amount to travel through that system and to spread out to where we’re seeing it this much.
“Unfortunately, that means that it will be in the system for a long time until it flushes out.”
Residents first reported foul smells along the greenway in the area of Barton Drive early last year, however it took until the summer to discover the first leak location. The investigation was later turned over to TDEC’s Division of Underground Storage Tanks after testing in September found petroleum constituents present in the samples.
The state agency required nearby tank owners to conduct testing of their underground storage systems as well as investigate potential soil and groundwater contamination, which found the systems to be in compliance with existing regulations, according to Schofinski.
A dye trace study was then conducted which found that groundwater from the East Main Street gas station property flowed directly to the affected area, according to Wagner. He added that the petroleum samples taken from the seep locations lacked a specific compound that was first added to gasoline in the 1980’s, which could mean the leak occurred three decades ago or longer.
“There have been petroleum products on that site for many, many years,” Wagner said. “By (the existing tanks) being in substantial compliance, that leads me to not believe it’s the current tanks. I think it’s a historic legacy issue.”
Regardless of when the leak occurred, TDEC has required the gas station’s tank owner to conduct interim corrective action onsite, according to Schofinski. The company will also be required to submit a plan to remediate the affected areas as well.
While the petroleum is contaminating Town Creek, Wagner said the leak is a “very mild” health concern to the public. Testing of the samples have also determined that the chemicals do not pose any fire or explosion risk.
“You get the same exposure filling up your tank with gas at the gas station and smelling the fumes,” Wagner added. “You get the same exposure changing the oil in your car.
“No one has been evacuated and the state has consistently said that this is not a life, health and safety (risk) scenario.”
The amount of petroleum coming out of the ground in most of the affected areas is expected to decrease with fewer rainfalls this summer. However, the leak will remain the most noticeable closest to the creek.
Officials with the city’s stormwater utility program plan to hold a community meeting within the next month for any residents interested in learning more about the petroleum leak. A date and location for the meeting have not yet been determined.
For more information about the case, including homeowners who want to report a new leak location, contact the Gallatin Engineering Division at (615) 451-5965.