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Mr. Jeffery Wong Page 2 The most recent depth to water measurements at the Harry's Auto site showed water levels to be approximately 42 feet below grade. Underground Storage Tank Removal On April 12, 1989, four USTs (one 2,000 gallon, two 550 gallon and one 300 gallon) were removed from the subject site by North Cal Construction of Stockton, California. The contents of the USTs apparently had consisted of gasoline. One soil sample was collected from beneath each of the smaller USTs at depths ranging from 9 to 10 feet. Two samples were collected at depths of 11.5 feet from beneath the 2,000-gallon UST. In addition one soil sample was collected from a depth of 3 feet beneath a product line. The samples were submitted to State-Certified FGL Environmental Laboratories for analysis. Each sample was analyzed for total petroleum hydrocarbons (TPH) using modified EPA Method 8015; for benzene, toluene, ethylbenzene and xylenes (BTEX) and ethylene dibromide(EDB)by EPA Method 8020 and for total lead by EPA Method 7420. Elevated concentrations of TPH and BTEX were detected in the samples collected from beneath Tank #l, Tank#2 and the product line. No detectable concentrations of TPH or BTEX were found in the samples collected beneath Tank#3 or Tank #4. No detectable concentrations of EDB were found in any sample. Total lead concentrations appear to be within the range of naturally occurring, background concentrations. Analytical data are summarized in Table 1. UST and soil sample locations are depicted on Figure 2. Soil and Groundwater Investigation At the direction of San Joaquin County Public Health Services, Environmental Health Division (PHS/EHD), Ground Zero conducted a subsurface investigation in order to evaluate the lateral and vertical extent of soil contamination, as well as the potential impact to groundwater. On February 22 and 23, 2000.eight soil borings were advanced at the site. Borings SBI and SB2 were drilled in the vicinity of the former tank pit. SB 1 was converted into groundwater monitoring well MW 1. Borings SB3, SB3a through SB3c, SB4 and SB5 were located peripheral to the former tank excavation. The locations of the borings and the monitoring well are shown on Figure 3. Soil samples collected from borings SBI and SB2 indicated detectable concentrations of gasoline hydrocarbons to 80 feet below ground surface (bgs). The remaining borings had no detectable amounts for the target analytes. No oxygenated additives were detected in any soil sample. Soil analytical results are summarized in Table 2. Groundwater sampled from well MW 1 contained relatively high concentrations of TPHg and BTEX. No oxygenate additives were detected in the groundwater sample. Analytical results for groundwater are summarized in Table 3. The results of the investigation were reported by Ground Zero in the Subsurface Investigation Report dated April 12, 2000. PHS/EHD responded to the report in a letter dated July 24 in which a workplan for additional investigation was required. Hanys\reports\workp1an3mws