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Mr. Marty Hartzell Page 2 of 10 The test wells VW la and VW1b are constructed of 2-inch diameter PVC casingand test well VW2 is constructed of flinch diameter PVC casing. All wells were completed with 0.10 inch slotted screen and pea gravel filter pack. The screened intervals of the wells are as follows: VW la: 23 —26 feet below grade VWlb: 38 —42 feet below grade VW2: 24—44 feet below grade State-licensed V&W Drilling (C57-720904) completed the drilling and well construction. The dual completion well (VW1a/VWIb) is located at the northernmost corner of the former UST tank pit and well VW2 is located just south of the former tank pit. The locations of the wells are shown on Figure 2. Logs of the vapor test wells are included in Attachment A SOIL SAMPLE ANALYSTS Selected soil samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) by EPA Method 8015, and for benzene, toluene, ethylbenzene and xylenes (BTEX) by EPA Method 8020. Samples selected for analysis were based upon field evidence of contamination and changes in lithology. The following samples were analyzed for TPHg and BTEX: • VW1: 15, 20, 25, 35, 40, and 42 feet below grade VW2: 20, 25, 30, 35, 40, and 44 feet below grade In addition, the soil sample collected from VW2 at a depth of 40 feet below grade was analyzed for total lead by EPA Method 7420 and the sample collected from VW1 at 40 feet below grade was analyzed for soluble lead by EPA Method 6010/200.7, 239.2. State-certified Argon Laboratories (FLAP 2359) performed analysis. Soil analytical data are summarized in Table 1. Laboratory data sheets and chain of custody documentation are included in Attachment B. Analytical results of soil samples collected during the drilling of VW1 and VW2 indicate that residual petroleum hydrocarbons previously detected at the site have been delineated and are limited to a small area beneath the former gasoline tank at depths ranging from approximately 12 to 45 feet below ground surface (bgs). The samples collected at a depth of 40 feet bgs in wells VWl and VW2 contained 130 parts per million (ppm) and 14 ppm, respectively. VWI and VW2 are located approximately 4 feet and 15 feet, respectively, from boring SB 1, which contained 30,000 ppm TPHg at a depth of 40 feet. These analytical results indicate that soil contamination did not spread laterally to any significant degree and attenuated rapidly below 40 feet. A sample collected from boring SB 1 at a depth of 45 feet bgs contained only 1.6 ppm TPHg and a sample collected at 35 feet bgs recorded only 5 ppm on the PID. A cross-section illustrating soil stratigraphy and the extent of residual contamination beneath the site is shown Figure 3. The figure illustrates that the gasoline released from the tank migrated vertically through the relatively coarse soil until it came in contact with the relatively impervious silt zone at approximately 38 feet bgs. This silt layer retards further vertical • migration of contaminants. In addition, a zone of fat clay between the depths of approximately 48 and 52 feet bgs would also presumably act as barrier to vertical migration. The non-detect results of 0:4)�«RO��d\RWo�\ doc