Back hoes and safety fencing obstructed the parking area at the J & J Corner Store at 4192 Harry Byrd Hwy this week as crews worked to replace a leaking fuel storage tank on the property. The leak in the premium gasoline tank was discovered by automatic monitoring equipment on November 4, 2010. As a result, the store owner had the tank tested using a technique called “tightness testing” which involves taking the tank out of service and measuring the amount of product in the tank over a period of time. The testing company reported that the tank had failed the test on November 12, 2010.
The Virginia Department of Environmental Quality (DEQ) required the owner to install two monitoring wells to determine whether a significant release had occurred. The wells were installed and immediately showed significant amounts of fuel. One well had 8 feet of gasoline in it and the second well had 3 feet. The owner was required to begin removing gasoline from the monitoring wells immediately using a a vactruck. DEQ also required the owner to perform a site characterization investigation, and to remove the tanks.
The investigation included the sampling of the nearest drinking water wells. Low levels of petroleum compounds were detected in the well that serves the store and a rental house next to the store on Shepherd’s Mill Rd. The well serving the adjacent house was also impacted with low level petroleum compounds.
DEQ representative David R. Forrer said , “Although the contaminant concentrations did not exceed EPA’s safe drinking water standards, DEQ immediately installed carbon filtration units to treat these drinking water supplies. Contamination has not been detected in the other drinking water wells, but the consultant will continue sampling them periodically.”
Ten monitoring wells have also been installed to characterize the extent and direction of contaminant migration. Gasoline has been extracted from 5 of the ten wells. Shortly after their installation the environmental contractor was able to remove 330 gallons of gasoline from the water table, but Mr Forrer indicated that the recovery has dropped off significantly. “So it appears that very little free phase gasoline remains.”
All 3 of the underground storage tanks were removed on February 3, 2011. A single corrosion hole was discovered in the bottom of the tank that had failed the tightness test. Once pulled from the ground there was not a significant amount of fuel around the tank. Mr Forrer said, “Other than a sheen on water in the excavation, no significant amount free phase gasoline was present in the tank basin, which implies that the consultant’s product removal system was extremely effective. We were encouraged by this, but groundwater cleanup and monitoring will continue for many months.”