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N " In July 1999, we drilled an additional monitoring well (MW-12) and a vapor boring to 80 feet, which I was completed for a vapor extraction well , (VW-7) . This was reported in our report dated August 5, 1999. In December 2000, we drilled one additional monitoring well (MW- 13) which was placed near (MW-8) so that the slotted casing would be located at a shallower level than (MW-8) . This was reported in the Drilling Activity Report dated December 14, 2000, In July 2005 , we drilled two monitoring wells (MW- 14 and MW- 16) which were placed near the east side of the station and across Charger Way and Grant Street. In this report we also described the finding of boring (B-4) at the southeast side of the station . This was reported in the Drilling Activity Report dated August 24, 2005. C. GEOLOGY The site and all nearby terrain are underlain by non-marine sediment which are tentatively assigned to the Modesto Formation of Pleistocene age . The materials penetrated at this site are clay, silty clay and clayey silt. Sandy strata are present between 25 and 30 feet and below 50 feet interbedded with silts and silty clay. Bedding is absent or non-distinct but appears to be essentially horizontal . D. Surface Water The closest surface water is the Stockton River channel about 1 mile northwest of the site . The San Joaquin River Walker Slough is about 2 miles south of this site. E . Local Land Use The property is a commercial gas station . The site west of this site is a restaurant and to the east is a hardware store. South of Charter Way is a series of small commercial buildings and north of this site is a residential area . Groundwater Concepts The contaminate framework is groundwater flowing from west to east. The geology under this site is mostly silty clay and clay with the most permeable areas are between 58 and 60 feet, 63 to 67 feet, 80 to 100 feet, 141 to 158 feet. The mass of contaminates is in the area from MW- 1 to MW-5 and extending east across Charter Way to the east southeast. The Hydraulic Conductivity of the groundwater was tested on April 30, 1993 in wells MW-4, MW-5 and MW-6. The conductivity was found to be 2. 94 feet/day. The depth of the water table is 33 feet and the soil unit was silty sand . This sand extends from the western well MW-9 to just beyond well MW-8. The average gradient for this site is to the northeast at 0.00345 and the velocity is calculated to be 0.07203 feet per day. During any quarter the water will travel about 6 . 3 feet. 4