Problem
This facility is an active retail fueling facility located at 19516 Highway 44 & CR 44B in Eustis, Florida. Closure assessment was required for the existing underground storage tank system (UST) at this facility when the UST system was upgraded (Picture 1, Picture 2, Picture 3, Picture 4, Picture 5, & Picture 6).
Solution
Soil samples were collected for field screening during excavation of the USTs on a horizontal grid of approximately 5 ft by 5 ft and a vertical grid of 2 ft. Field screening of soil samples for petroleum vapors was conducted using the headspace testing procedure as specified in Chapter 62-770, Florida Administrative Code (F.A.C.). A soil boring was installed adjacent to each of the three dispensers and three additional borings were installed along the product piping. One soil sample was collected from the tank pit and one soil sample was collected from one of the dispenser island borings for laboratory analysis. Following removal of the USTs, a temporary groundwater monitoring well was installed within the tank pit, in the location of the highest soil vapor readings. Groundwater samples were collected from this well for laboratory analysis.
Laboratory analytical results for the two soil samples collected for analysis reported all analytes as not present at their respective method detection limit and the limit of detection achieved by the laboratory for each analyte was below the respective Leachability Soil Concentration Target Level specified by Chapter 62-777, F.A.C. Groundwater analytical results for samples collected from the temporary well reported all analytes as not present at their respective limit of detection and those limits of detection were reported as below the respective Groundwater Cleanup Target Level specified for each analyte by Chapter 62-777, F.A.C.
Based on these results, TERRA-COM concluded that the requirements for UST closure assessment were met and that no additional assessment was required.