Support Platform CS01- Treating Clay Lithology
SITE
Gentry Oil, LLC (Active Bulk Fuel Storage Distribution Facility), DeLand, FL FACID:8622760
CONTAMINATION
Gasoline Range Organics in ground water
BACKGROUND
A release of gasoline fuel from a UST at this facility led to soil and groundwater contamination. The only prior remediation action taken at the site was the excavation of approximately 60 tons of soil from the tops of the USTs upon their closure. The site lithology consists of clayey sand and sandy clay. The Support Platform (SP) in conjunction with EN Rx Reagent was selected for remediation at the site upon complete site characterization.
SUMMARY OF ACTIVITIES
- Baseline sampling was performed prior to the
installation of the Support Platform - The SP began running in August of 2019 and injected EN Rx Reagent into 20 vertical and horizontal wells.
- Approximately 35,000 gallons of reagent was
proposed to be injected in an around the tank vault. - The SP system was adjusted to inject the maximum volume into the clayey lithology while avoiding surfacing.
- First quarter sampling revealed additional mass in three wells in the abandoned UST area.
- The SP customizing options allowed for targeted
treatment to the desorbed areas.
RESULTS
Although remediation activities are still underway, the sampling results show large reductions in BTEX concentrations among the monitoring wells surrounding the UST area. The desorption that occurred during the beginning stages of injection are evident in the 12/15/2019 sampling data. The continued treatment over the next two quarters has shown reductions in all wells of 90% and greater and is now showing exceedances of only one constituent.
ND = Non-Detect
CONCLUSION
The site treatment using the Support Platform coupled with the EN Rx Reagent has led to a large reduction of the contaminant plume and is on its way to below GCTLs in all key wells. The following benefits were observed.
- SP unit allowed adjustments to be made to the injection plan when sampling data indicated more mass was present with no additional mobilization cost.
- The slow nature of both the controlled reagent and the SP unit allow for use around the tanks with no adverse effects.
- Robust amounts of reagents can be applied even in tight lithologies.
- Desorption time is incorporated into the plan.
- The engineer can control where to place the reagent in real time based on data, all from the web portal.
