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<br />S.0 FINDINGS/CONCLUSIONS <br />In summary, the findings of the subsurface site investigation are as follows: <br />• Areas of pooled free diesel product were observed within bermed area of the AST <br />system and oil staining was observed on concrete surfaces in the vicinity of the AST <br />system. <br />• In general, sandy soils with clay, gravel, and cobbles were encountered in the seven <br />boreholes advanced in the vicinity of the AST system. Saturated soils were encountered <br />at depths less than 2 feet below ground surface in all of the boreholes advanced. <br />• Based on monitoring well survey data and depth to water measurements, groundwater <br />beneath the site flows toward the northeast. At the time depth to water measurements <br />were collected from monitoring wells, the groundwater level was less than 1 foot below <br />the ground surface in wells located to the southeast, east, northeast of the AST system. <br />• Laboratory results for four of the eight soil samples analyzed indicate the presence of <br />TEI'1~ in concentrations exceeding the State Remedial Action Category II (RAC Il). <br />Analytical results for the soil samples indicate the presence of low concentrations of <br />toluene in sample SFI-2:2.5, ethylbelrzene iIt samples SH-1:2.5 and SH-2:2.5; and <br />xylene in samples SH-1:2.5, SH-2:2.5, and BFI-16:1-3. No BTEX constituents were <br />indicated at concentrations above the laboratory detection limit in the remaining five <br />soil samples. Benzene was not indicated above the laboratory detection limit in any of <br />the soil samples analyzed. <br />• Laboratory results for groundwater samples submitted for analysis indicate low <br />concentrations of TEPH in groundwater from two of the six wells. Analytical results <br />for the groundwater samples low concentrations of benzene, toluene, ethylbenzene, and <br />xylene in samples SH-1 and MW-11. BTEX constituents were not indicated at <br />concentrations above the laboratory detection limit in the remaining groundwater <br />samples. None ofthe groundwater sample analytical results exceed the State MCLs. <br />6.0 RECOMMENDED REbIEDIAL RESPONSE <br />Based on analytical results presented in the subsurface site investigation report, dissolved <br />TEPH and BTEX constituents in ground water do not exceed state 1viCLs, therefore, only <br />free-phase diesel product recovery is addressed in this recommended remedial response. <br />Measures should be implemented to immediately address recovery of the free-phase diesel <br />product at the site. To facilitate the recovery of free-phase diesel product, ERM-Rocky <br />Mountain, Inc. recommends the following: <br />ERM-ROCKY MOUNTAW, MC. <br />P:\IOOOISWPCl96I0I9VtEPOR7.DOC Printed on Recycled Paper <br />9 <br />