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Site History
<br /> • 14000 Highway 88,Lockeford,GA
<br /> Time Oil Property No 04-049
<br /> Site Assessment-August 1992
<br /> On August 26, 1992, a sod vapor survey was performed to assist in determining the extent of impacted soils
<br /> A pneumatic hammer was used to drive 13 soil vapor probes to depths of up to 13 feet in the vicinity of the
<br /> former tanks Vacuum pumps and charcoal tubes were used to collect vapor samples from each probe at
<br /> various depths Immediately after collection, each sample was submitted to an onsite mobile tab where it
<br /> was extracted and infected into a gas chromatograph Due to the presence of hardpan dust below the ground
<br /> surface, the results of the soil vapor survey were limited, as no probes could be advanced deeper than 13
<br /> feet
<br /> During the week of September 28, a drill rig was used to advance 4 soil borings and install 3 vapor extraction
<br /> wells and 3 vapor inlet wells During field activities, soils were found to consist of hardpan to approximately
<br /> 15 feet, this strata was underlain by loose fine to medium sands Dense silty sands and sandy silts were
<br /> generally encountered at depths of 30 to 35 feet to the extent of the borings Groundwater was not
<br /> encountered during field activities
<br /> Drilling at each location was continued until hydrocarbons were no longer indicated by field instrumentation
<br /> Accordingly, borings SBA, SB-2, and SB-4 were terminated at a depth of 40 feet while SB-2 (W1) was
<br /> advanced to 45 feet Wells W3, W5, and W6 were installed to 40 feet, while W4 was installed to 30 feet and
<br /> W2 was installed to 45 feet Wells W1, W2, W3 were installed as 4" diameter vapor extraction wells, and
<br /> wells W4, W5, and W6 were installed as 2" diameter vapor inlet wells Although each well was constructed
<br /> using 0 020 slotted casing, screened intervals vaned depending on well depth and field observations
<br /> . Three soil samples from each boring were submitted for analysis based on field screening and visual
<br /> observation (Only 2 samples were submitted from W3 ) Each sample was analyzed for TPH, BTEX, and
<br /> ethylene dibromide Results indicated that sod contamination was generally limited to the area of the former
<br /> tanks and appeared to exist at a depth of 30 feet to 35 feet The highest concentrations of contaminants were
<br /> indicated in 30-foot samples collected from W1(SB-2), W2, and SB-2 Samples collected from a depth of 15
<br /> feet in SB-1 and W3 contained 200-300 ppm gasoline, however, samples collected at 30 feet contained less
<br /> than 10 ppm gasoline Samples collected from SB-4, W4, W5, and W6 contained trace to "non-detect"
<br /> concentrations of contaminants None of the samples collected from depths of 40 feet to 45 feet contained
<br /> detectable concentrations of gasoline or its constituents
<br /> After the installation of the wells, a vapor extraction pilot test was performed on W1, W2, and W3 to evaluate
<br /> the feasibility of in-situ remediation by vapor extraction The results of the study indicate that soil vapors can
<br /> be easily extracted from the existing wells and that vapor extraction appears to be appropriate for site
<br /> remediation
<br /> Based on the results of the site investigation, it appeared that impacted sods were limited to the former tank
<br /> excavation and the more dense soils encountered at a depth of 30 feet Although several of the soil samples
<br /> submitted for analyses contained trace concentrations of hydrocarbons, SB-4, W4, W5, and W6 generally
<br /> defined the extent of sod contamination to the west, southwest, north, and south of the tanks
<br /> A copy of Canonie's"Site Assessment Report"was forwarded to the appropriate regulatory agencies on May
<br /> 25, 1993 In their reply dated June 18, 1993, the PHS/EHD requested that a workplan for an additional
<br /> investigation to verify the extent of soil contamination be submitted
<br /> SLorkplan for Additional SitQ Activities-OctQber 1993
<br /> A copy of Science and Engineering Analysis Corporation's (SECOR) "Workplan, Additional Environmental
<br /> Investigation" was forwarded to the appropriate regulatory agencies on October 20, 1993 The goal of the
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