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• separates the silty clayey sand A zone aquifer from. the B zone aquifer that is found at approximately 21 feet bgs and is approximately 6 to 7 feet thick The B zone aquifer consists of cleaner moderately sorted fine to coarse sand that shows graded bedding (fine to coarse with depth) Beneath the B zone aquifer is stiff clay that extends from approximately 27 feet bgs to 40 feet bgs The original five monitor wells did not encounter groundwater in the A zone aquifer when initially drilled and sampled Depth to water measurements taken between 1993 and February 1996 indicate that the A zone aquifer was dry (depth to water greater than 17 feet bgs) MW1 through MWS are screened across both the A and B zone aquifers Sometime after February 1996 depth to groundwater measurements indicated that groundwater was in contact with the A zone aquifer, see Table 1 The groundwater in the vicinity of the site is semiconfined Groundwater elevation at the site varies from a wet year high of 7 feet bgs (silty clay formation above the A zone) to about 22 - 23 feet bgs (B zone) during the previous drought period Groundwater flow direction in the A zone at the site has generally been to the west since December 1997 The B zone shows a similar flow direction, which would be expected due to the connection between zones at wells MWI through MW5 2ND QUARTER 2004 SINCE AC'TIVI'TIES Groundwater samples were obtained from all active wells associated with 1876 Country Club Blvd during this quarter (April 15, 2004) As requested by San Joaquin County Health, WEGE and Advanced GeoEnvironmental, Inc (AGE) are to coordinate depth to water and groundwater samples on the same date WEGE monitored and sampled wells associated with the Sanchez Property, 1876 Country Club Boulevard AGE obtained depth to water measurements from the monitored wells associated with Country Club Food and Fuel, 1856 Country Club Boulevard Figure 3 - Site Base Map has been expanded to show the relative positions of the Country Club Food and Fuel wells to the Sanchez Property wells Field notes from site monitoring and sampling can be found in Appendix A DEPTH TO WATER MEASUREMENTS Depth to water was measured at all active wells on April 15, 2004 The measurements were made from the surveyed elevation at the top of casing at each well using an electrical air/water interface probe (Table 1) No free product or product sheen was observed in any of the monitor wells Table 1 also presents the Depth to Water measurements obtained from wells located at Country Club Food and Fuel Charts have been developed to show the elevation changes with time for Sanchez wells MWI, MW 2, MW3, MW4 and MWS, see Appendix B Western Geo-Engineers surveyed the top of casings for temporary piezometers on February 5, 2003 using level and rod • 4 Sanchez QM 2nd 2004