Site Profiles - View. General Information. Contaminants: Site Hydrology:

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1 Site Profiles - View General Information Site Name and Location: Description: Historical activity that resulted in contamination. Tiger Cleaners Memphis, Tennessee, United States Tiger Cleaners is located in the Bellbrook Retail and Industrial Complex, Memphis, Tennessee. It is part of a strip-mall type structure built between 1965 and 1984.The subject site has been utilized as a drycleaning facility since The main contaminant source area is located beneath the drycleaning machine in the rear of the facilty. A secondary source of contamination is located just outside the back door of the facility where filters were drained. Contaminants: Contaminants: Contaminants present and the highest amount detected in both soil and groundwater (please avoid giving ranges). Other Contaminants Present: Indicates what other contaminants were found on-site Deepest Significant Groundwater Contamination: Contaminant Conc in GW Conc. in Soil cis-1,2-dichloroethene 26,300 µg/l mg/kg Tetrachloroethene (PCE) 20,000 µg/l 4,313 mg/kg trans-1,2-dichloroethene 1,913 µg/l mg/kg Trichloroethene (TCE) 16,985 µg/l mg/kg Vinyl Chloride 2,800 µg/l mg/kg The highest concentration found was in MW-12 located near the rear of the facility. The well is 12 ft bgs (screened at 10ft) Plume Size: Approximately 20,000 square feet(.5 acre) Site Hydrology: (1 of 5)2/2/2006 5:09:14 PM

2 Depth to Groundwater: Lithology and Subsurface Geology: Conductivity: Gradient: Media: Media: 5-9 ft bgs Clayey silt surface-11 ft bgs Silt ft bgs Clayey silt ft bgs Silt ft bgs Clayey silt ft bgs Fine sand ft bgs Medium sand ft bgs ft/day (based on seasonal and soil variations) ft/ft Groundwater Soil Remediation Scenario: Cleanup Goals: Technologies: Technologies Used: Goals are site- specific based on potential receptors, risk assessment and other factors. The State of Tennessee uses the EPA's Clean Water Act MCLs for groundwater and the EPA Region 9 PRG's for industrial soil as screening tools. Site specific goals may be calculated. In Situ: Bioremediation Hydrogen Release Compound (HRC) Other technologies used: Why the technology was selected: Date implemented: A passive soil-gas survey (EMFLUX )was utilized to delineate the contaminant plume before groundwater monitoring wells or DPT soil sampling was conducted. This was helpful in pinpointing contaminant hot spots. The Regenesis HRC technology was selected because studies estimated the cost would be lower in comparison with other in situ bioremediation and in situ chemical oxidation technologies. April (2 of 5)2/2/2006 5:09:14 PM

3 Final remediation design: The HRC application (glycerol tripolylactate) was conducted April 22-26, Prior to the application, eight groundwater monitoring wells, which delineated the plume extent, were sampled to quantify baseline groundwater contaminant concentrations. In the source area, where the highest soil contaminant concentrations were detected at 4-6 ft, a directional drill rig was used to inject a total of 1,080 lbs of HRC into 4, 40-ft horizontal borings beneath the Cleaners, at depths ranging from 7-9 ft below the floor surface. Outside the source area, a Power Probe with an expendable carbonsteel point and a Geoprobe grout pump were used too complete 105 vertical injections. At eight locations, 100 lbs of HRC was injected into each boring along the fire-main trench located outside the Cleaners (upgradient and adjacent to MW-12), from a depth of 3-13 ft bgs (total 800 lbs). At 97 locations, approximately 21 lbs of HRC were injected into each boring in the contaminant plume, from a depth of 3-9 ft bgs (total of 2,120 lbs). Results and Next Steps: Results to date: The eight ground water monitoring wells are being sampled quarterly to monitor contaminant and bioenvironmental conditions. To date, seven quaters of monitoring data is available. Baseline sampling indicated that the most significantly impacted monitoring well (MW-12) had PCE and TCE concentrations of 1,790 1 µg/l and 1,758 µg/l respectively, prior to HRC application. These concentrations are 90% less than the highest detected. The latest quarter of data indicates a decline in PCE with respect to baseline concentrations. This decline is about 40% for the most impacted well and as much as 90% in other source area wells. PCE shows a consistent pattern of decline for all quarterly data from the source area samples. The most impacted well, and the wells immediately downgradient, however, exhibit some fluctuation within the downward trend. TCE concentrations at the most impacted well have also fluctuated above and below baseline levels with the latest quarter of data, indicating an increase above baseline conditions but an 86% decrease below the highest detected at the site. Downgradient wells indicate slightly fluctuating-to-steady TCE concentrations. Source area wells indicate an overall decline in TCE. Other degradation by-products (DCE and VC) have indicated a flucuating trend above and below baseline limits with the largest degradation by-product concentration occurring at the most impacted well. There were no indications that contaminant plumes have migrated or advanced beyond previously defined boundaries. (3 of 5)2/2/2006 5:09:14 PM

4 Next Steps: It is not certain if the noted decline in parent product, when compared to baseline concentrations, is a result of the HRC remedy. In the most impacted well, the largest reduction in contaminant concentration (from NAPL) to dissolved phase concentrations) occurred prior to HRC injection. The cause of the decline is unknown; however, potential lab result discrepancies have been identified with some of the reported data. In addition, favorable reductive groundwater conditions are not supported by the geochemical data although a slight increase of respiration by-products (CO2) and degradation byproducts (cl-) during some quarters seem to indicate active biodegradation. 1. Comprehensive review of site analytical and geochemical data along with collection and analysis methods. 2. Considering ISCO application to reach cleanup goals. Costs: Cost for Assessment: Cost to Design and Implement: Cost for Operation and Maintenance: Total Costs for Cleanup: $76,044 $124,524 Lessons Learned: Lessons Learned: 1.A thorough understanding of site geochemistry is required to understand effect of HRC on groundwater. 2. It is unclear how much time will be necessary before complete cleanup by HRC can be acheived. 3. In evaluating the cost of implementing this technology, monitoring costs should be included as these costs can be significant (4 of 5)2/2/2006 5:09:14 PM

5 Contacts: Principal Point of Contact: Pam Franklin TN Division of Superfund 711 RS Gass Blvd Nashville, Tennessee (615) Site Specific References: Site Specific References: Images: Images of Site: Tiger Cleaners Site File Profile last updated on Nov 03, (5 of 5)2/2/2006 5:09:14 PM