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06 June 2001 AGE-NC Project No. 98-0533 Page 2 of 5 3E@15'from beneath USTs#1 and 93 at concentrations of 20 micrograms per kilogram(µg/kg),27 gg/kg, and 8 µg/kg, respectively. Total lead was detected in soil sample 3E@15'at a concentration of 324 mg/kg. On 21 and 22 June 2000, four soil borings were advanced at the site; three of the boring locations were subsequently completed as ground water monitoring wells MW-1, MW-2 and MW-3 (Figure 2). Three ground water monitoring events to date indicated a general ground water flow towards the east (southeast in July 2000 and northeast in November 2000 and February 2001. Although all detected analyte concentrations in the wells are low and within California Maximum Contaminant Levels (MCLs) for drinking water, the southernmost monitoring well (MW-2) consistently has the higher contaminant levels.Methyl tert butyl ether(MTBE)was detected at a low concentration in a ground water sample from MW-2 (1.6 micrograms per kilogram - µg/kg) in July 2000, and MTBE was detected in a soil sample from a depth of 15 feet bsg from the MW-2 pilot boring.Mapping the data (Figures 3, 4 and 5) shows that the contaminates detected in MW-2 soil and ground water samples may be the north leading edge of plumes of impacted soil and/or ground water that is not assessed further toward the south. Complete background information and details ofprevious investigations at the site is included in the reports titled Underground Storage Tank Removal Report dated 11 January 2000, and Preliminary Site Assessment Work Plan. 3.0. SCOPE OF WORK Based upon analytical results of soil and ground water samples collected to date, additional investigation is needed to determine the southern lateral extent of hydrocarbon-impacted soil and ground water. To complete assessment of impacted soil and/or ground water, AGE proposes to advance one soil boring to a depth of approximately 70 feet bsg south of MW-2 to collect soil and ground water samples for laboratory analysis. Completion of the scope of work will involve the following tasks: • Permitting and pre-field work activities; • Soil sample collection and analysis; • Ground water sample collection and analysis; Advanced GeoEnvironmental,Inc.