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%W -W \.+/ Site Background Information: former Tracy Diner Page 3 of 4 • The fuel additive MTBE was detected in three of the four soil boring ground water samples at concentrations of 28 Ag/1(B6 and B9) and 8.7 pg/l (B8). • Dissolved lead was not detected at or above laboratory reporting limits in the any of the ground water samples. SOIL EXCAVATION On 23 October 2000, hydrocarbon -impacted soil at the former northern dispenser area was removed with an excavator and 2.45 cubic -yard bucket and stockpiled on the eastern edge of the site. Excavated soil was field screened for the presence of volatile organic compounds using an organic vapor meter (OVM). Ground water was present within the limits of the excavation at a depth of 15 feet bsg. On 20 and 21 October 2003, hydrocarbon -impacted soil north of the October 2000 excavation area was removed with an excavator and 2.45 cubic -yard bucket and stockpiled on the eastern edge of the site. Excavated soil was field screened for the presence of volatile organic compounds using an OVM. Ground water was present within the limits of the excavation at a depth of 13 feet bsg. On 21 October 2003, the excavation was halted due to the discovery of one 500 -gallon UST. On 05 November 2003, the UST was removed under the supervision of the EHD. Excavation activities resumed on 10 November 2003 and continued until 12 November 2003. At this time, the excavation was backfilled with clean fill material. Saturated soil was excavated from below the water table and stockpiled on-site within a soil containment berm. Soil was placed on plastic sheets for temporary storage. The open excavation area was surrounded by caution fencing. No AGE or subcontractor personnel was allowed into the excavation area. On 27 July 2004, two soil borings were advanced at the site for the collection of soil samples and the installation of two ground water monitoring wells (MW -6 and MW -7). The monitoring wells were developed on 05 August 2004, sampled on 09 August 2004, and surveyed on 16 August 2004. MW -6 and MW -7 were completed as ground water monitoring wells using 2 -inch diameter PVC casing with a 0.020 -inch slotted screen installed from approximately 5 feet to 20 feet bsg. The filter pack (No. 3 Lonestar sand) was installed from 4 feet to 20 feet bsg, and a nominal 1 -foot bentonite chip plug was installed above the filter pack and hydrated. The wells were grouted to near the surface with portland cement, and water -tight, traffic -rated well boxes were installed over the wells. A total of five soil samples were analyzed for petroleum hydrocarbon constituents. TPH-g and TPH-d were detected in the soil sample collected from boring MW6-15H at concentrations of 3.5 mg/kg and 37 mg/kg, respectively. On 30 June 2005, three soil borings were advanced at the site for the collection of soil samples and Advanced GeoEnvironmenlal, Inc.