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t 15.5 foot sample (See Drill Log) . Field inspection and PID testing did not record the presence of organic vapors or visual staining of soils typically associated with waste oil F contamination in Boring SB2 to a depth of 17.5 feet, Slight to strong gasoline hydrocarbon odors were noted in boring Sa3 to a depth of 31.5 feet, the maximum depth explored. PID readings in the 20.5, 25.5 and 30.5 samples were 4751, 4122, and 1400 ppm, respectively. The depth to first 3 => groundwater beneath the site was recorded approximately 32 feet below grade in boring SB1. 4.2 Laboratory Analysis - Soil The laboratory analysis of samples collected at 20.5, 25.5 and 30.5 feet in boring SB1 did not record the presence of BTEX above the 0.02 ppm method detection limit. The TPH-G concentrations in these samples and the TPH-PT concentration in the 30.5 foot sample were not detected above the 5.0 ppm ' z detection limit (Table 1). Elevated concentrations of BTEX and TPH-G were recorded in the 20.5, 25.5 and 30.5 samples from boring SB3. The 30.5 foot sample exhibited the highest t: . levels with BTEX and TPH-G concentrations of 215, 967, 279, 1358 and 11089 ppm, respectively. The laboratory test results for these samples, including BTEX concentrations, are summarized in Table 2. The 11.5 and 16.5 foot samples from boring SB2 did not record EPA 8010 constituents, including Chloroform and Trichloroethane, above method detection limits (Table 3). Laboratory data sheets, chain of custody forms and laboratory quality control data are presented in Appendix IV. t 5.0 CONCLUSIONS The result of field inspection and laboratory analysis of soils collected during tank removal and subsequent borings r drilled within the former tank pits, indicate hydrocarbon contamination has occurred a a result of leakage of gasoline product to the subsurface from Tanks A and C. The := absence of significant contamination in the pit sample from Tank B and the non-detectable concentrations of EPA 8010 constituents (including Chloroform and Trichloroethane) in samples collected from soil boring SB2 indicate no significant leakage of waste oil occurred at this location. Primary source co►ztrol has been achieved at the site with .. . ... . the...removal-.of...--the....three u/g......tanks. .and associated ;}, oduct.. __. ...._. .. lines. The only other source for continuing contar;'nation are the soils contaminated by the leakage of gasoline b product from Tanks A and C. The elevated concentrations of total petroleum hydrocarbons recorded in soils to a depth of 30.5 feet beneath Tank A indicates a significant volume .of gasoline has leaked. The highest TPH concentration detected .in the 30.5 foot sample, 4