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i Mr. Ron Rowe • Page 2 samples collected during the UST removal, but at depths of approximately 16.5 ft bgs. Analytical results for the sample collected beneath the smaller UST were not available. Results for the sample beneath the larger UST indicated TPH concentrations of 2,000 ppm and total xylenes at a concentration of 1,000 ppm. (Soil Assessment Report, 10-9-87. Kleinfelder. File #24-2072-1) On September 25, 1987 twelve soil samples were collected from a stockpile of soil removed during the tank removal. Four of the samples contained detectable concentrations of TPH. Laboratory analytical results indicated that one sample contained concentrations of TPH as diesel at 13 ppm. The other three samples contained concentrations of TPH as gasoline ranging from 170 ppm to 1900 ppm. The stockpiled soil had been segregated based on the sampling locations and laboratory results. (Soil Assessment Report, 10-9-87. Kleinfelder. File # 24-2072-1) In October 1987 Mr. Jay Friedman of Valley Volkswagen and Mr. Ray Walker of Walker Hydraulics backfilled the UST pit with the stockpiled soil. Apparently the petroleum hydrocarbon impacted soil was placed at the top of the backfilled UST pit. (Telephone Conversation Record, 10-27-87. Kleinfelder) In May 1995, three soil borings (SB1, SB2, and SB3) were advanced to approximately 46 feet bgs and monitoring well MW1 was installed to a depth of 62.5 feet bgs (see Figure 2). • The soil samples collected from soil borings SB1, SB2, and SB3 did not contain detectable concentrations of TPHg, BTEX, or Oil and Grease, except the 25.5 ft sample from SBI (0.010 ppm total xylenes). Total lead was detected in all of the samples at concentrations ranging from 6 to 10 ppm. Analytical results are summarized in Table 1. The soil samples collected from soil boring MW 1 (located in the center of the former UST pit) contained TPHg concentrations of 8,000 ppm and 8,800 ppm in the 20.5 ft and 30.5 ft samples, respectively. Benzene was not detected in any of the soil samples. Oil and Grease concentrations were detected at concentrations of 230 ppm, 140 ppm, and 50 ppm in the 10.5 ft, 20.5 ft, and 30.5 ft samples, respectively. Total lead concentrations were detected in all of the soil samples collected from boring MW 1 at concentrations ranging from 8 ppm to 61 ppm. The initial groundwater samples collected from monitoring well MW 1 contained TPHg concentrations of 850 parts per billion (ppb). Benzene was not detected, however toluene, ethylbenzene, and total xylenes were detected at concentrations of 5.2 ppb, 18 ppb, and 85 ppb, respectively. Total Lead and Oil and Grease concentrations were not detected in the groundwater samples. Discussion and Pro sed Sg= of Work The lateral and vertical extent of soil contamination appears to have been defined during the . phase of work completed in May 1995. Further investigation of the extent of soil contamination