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i • iIn July 1999 we placed one additional well (BM-12) about 200 feet east of this station No gasoline contamination was found in the soil i In November 2000 we drilled one vapor extraction well VW-7 to the east of the office at this station and small amounts of gasoline contamination were found from 45 feet bgs to 80 feet bgs Two borings B-2 and B-3 were also drilled to locate the bottom of the soil contamination in B-2 and test , ifor a possible leak of the tanks B-2 found no gasoline contamination below 85 feet bgs In December 2000 we placed well BM-13 to test the surface water of the east side of Grant Street This well was placed within 5 feet of wells BM-8 which was 65 feet deep Well BM-13 was 45 feet deep ' Groundwater Concepts ' The Hydraulic Conductivity of the groundwater was tested on April 30, 1993 in wells BM-4, BM-5 and BM-6 The conductivity was found to be 2 94 feet/day The depth of the water table was 53 feet and the soil unit was a silty sand This sand extends from the western well BM-9 to just beyond well BM-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 I , The San Joaquin County Flood Control and Water Conservation District measures the groundwater depth in the Spring and Fall of each year At present the report of their findings is that the groundwater is flowing northeast and the groundwater flow has been to the northeast every period for the time we have been the consultant at this site They were unable to perform this service during 2000 to 2003 for unknown factors They are preparing a report which we believe is to be presented in the spring of 2004 They allowed us to see their data and we found that the flow of the water remains to the northeast in 2003 The original boring HP-2 was dry at 50 feet We returned a week later and deepened HP-2 and I found water at 65 feet The fact that no water was flowing for 10 feet indicated that the water had encountered a soil unit which could not transmit water, the unit was a clayey silt When we drilled to a depth of 65 feet we'encountered water which was contaminated with TPH and BTEX We did not test this water for MtBE since the county did not require that test at that time The soil units which camed water at this level were fine clayey sand lenses about 2 feet thick The water table in 1995 was 46 feet below the surface and at present it is 35 feet This rise in the I water table caused the ground water flow to shift at the ARCO Station located at the comer of Stanislaus Street and Charter Way, to a more southerly direction However, we believe that the water deeper than 55 feet is still flowing to the northeast We believe this is occurring because the BTEX and MtBE levels in B-3 increased with depth We also believe that the water entering under the Sun Gardens building is coming from a site or sites west of our site There are two known tank leaks to the west, one at 641 East Charter Way and the ARCO station at 701 East Charter Way The site at641 East Charter Way had a boring (B-1) drilled in May 1998 Water and soil samples r• were obtained and tested The results are showed in Tables 3 and 4 This site was contaminated with BTEX and MtBE chemicals The results we have are limited, since the boring, B-1 was 5