STATE DEPARTMENT CONFIRMS PETROLEUM DISCHARGE UNDER GREENWAY TRAIL
Suspected Source Could be Leaky Underground Storage Tank or Discharge from Decades Ago
GALLATIN – The Tennessee Department of Environment and Conservation (TDEC) and the City of Gallatin are working to remediate remnants of petroleum-based product contamination that could be the result of a leaking storage container or discharge from decades ago. TDEC’s Division of Underground Storage Tanks is conducting initial research along Town Creek northeast of downtown Gallatin before beginning the remediation process in the spring.
“According to TDEC’s field investigation, they have categorized this is a ‘nuisance odor’ but not a health hazard,” says Gallatin Stormwater Utility Manager Lance Wagner. “While they try to pinpoint where the contamination originated, the remediation process will get underway to quickly resolve the odor issue in that area.”
TDEC’s inspection was prompted by complaints of odors on the greenway on the north side of Gallatin in September 2018. Through water and air sampling, low concentrations of petroleum-based products diluted in the air and in the groundwater were confirmed. Evidence of contamination was found in multiple springs/seeps under the City Greenway Trail and in multiple smaller seeps/springs on residential properties along Perrolee Street, Morton Avenue and Barton Drive.
In February, TDEC began drilling soil borings to test soil, installing groundwater monitoring wells to sample groundwater and determine flow direction, mapping the pathways in the underlying soil and bedrock using geophysics, and conducting dye-trace testing to determine water-flow direction and travel time. Understanding the underground drainage systems will help determine where remediation efforts should take place.
In order to immediately mitigate the distinct petroleum odor present in this area and begin the long-term remediation process, an activated carbon and nutrient solution will be injected into the soils and ground water in the affected area. The carbon will help adsorb the petroleum-based products limiting their ability to migrate into the air, and the nutrient mixture will start breaking down the petroleum-based products. These injections will start along the City Greenway and progress into residential yards and drainage ways. This method is anticipated to eliminate the odor in the area within three months, and bacterial agents will continue to clean up the system for another 15 years.
TDEC’s Division of Underground Storage Tanks will cover the costs of both the investigation and remediation since a leaky underground storage tank is suspected to be the source of the contamination.
Questions on this ongoing investigation should be directed to Lance Wagner or Jennifer Watson in the City of Gallatin Engineering Division 615-451-5968.