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I RECENT WORK ' On November 6, 2000 we dniled and sampled two bonngs Boring (B-2)was drilled to a depth of 100 feet below the surface (bgs) Sod samples were taken at 85 and 90 feet The original drilling of VW-7 on July 15, 1999 was sampled at 80 feet bgs and that sample was found to be ' contaminated with gasoline The three samples taken at B-2 at 85, 87 and 90 feet bgs were free of contamination of gasoline and the bonng was abandonded with hydrated cement ' Boring B-3 was also dniled to a depth of 100 feet to compare the geology between the two bonngs A soil gas sample was taken at 16 feet bgs to see if recent MtBE contamination was coming from the tank pit The sample registered Toluene and TPH gas at 28 8 and 64 0 mg/Kg ' This showed that gasoline vapor was present, however, no MtBE gas was present The soil and water sampling was done on November 7, 2000 ' Soil samples were,taken at 36 and 61 feet bgs The sample at 36 feet was directly below the present water table and the sample at 61 feet was taken to define the deeper soil The sample at 36 feet was,free,,of all BTE ,; TPH and Oxygenates, however, the sample at 61 feet had 16 ug/Kg of Benzene but no oxygenates 67�� Water samples were taken at 39, 50 and 60 feet bgs This sampling was done to define the contamination at different levels The BTEX and TPH levels increased from 39 feet to 60 feet These readings are recorded in Table 3 and 3B The increase in both benzene and TPH with depth is an indication that the water contamination around the tank pit is coming from another source The reason for this is that the lowest level of the groundwater in this area was in January 1993 when the level was about 55 feet below the surface The level of benzene and TPH contamination in 1993 was about 2700 and 5400 ug/L respectively These levels, almost 8 years ago, are below the levels found in this testing Because of natural attenuation and the length of time it is unreasonable to assume the concentration of these contaminates would rise Also it has been found that the flow of the groundwater to the northeast has been consistent over this period Using the hydraulic conductivity and the average gradient divided by 0 25 the assumed porosity, we find that the groundwater flows at about 87 5 feet per year Two known sources of contamination are to the southwest of this site, the ARCO Station and an abandonded station both being at the comer of Stanislaus Ave and Charter Way These stations are between 200 and 350 feet from this boring position and the water would take about 2 25 and 3 75 years to flow from their station to this station We checked the water for all 8260 chemicals and found that boring B-3 at 39 feet had 7 ug/L of 1- 2 DCA This chemical has been tested for in the past but it has never shown up in the water at this site This also indicated that the groundwater is migrating from another site MtBE was not found at 39 feet, however, at 50 and 60 feet it was 2 5 and 16 5 ug/L respectively This is the same scenario as with benzene, the increase with depth indicates a source not at our site Monitoring well BM-13 was drilled on December 7, 2000 on the sidewalk next to BM-8 BM-8 was completed on August 3, 1993 The slotted casing in this well was from 65 to 45 feet bgs At that time the water table was about 50 feet bgs At present the water table is at about 35 feet bgs • I4