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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 dulled 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) MWl through MW5 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 and Figures 8 and 9 The groundwater in the vicinity of time site is semiconfined Groundwater elevation at the site vanes 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 welts MW I through MW5 UPDATE ASSESSMENT In preparation for the over-excavation of gasoline contaminated soils associated with the previously removed UST and dispensing system a better understanding of the subsurface conditions was necessary This included five continuous core "Geoprobe" test holes to 1) help in the sitting and design of additional downgradient monitor wells and, 2) more closely examine the subsurface stratigraphy It also included the completion of three cluster wells RI A&B in the vicinity of the area to be over-excavated where aquifer tests could be performed to evaluate excavation dewatering needs and onsite hydrogeologic conditions and, two downgradient offsite cluster monitor wells MW6 A&B and MW7 A&B to evaluate the A and B zone aquifers and possible future remediation efforts 4'1H_QUA RTER 200.1_SITE ACTIVITIES As requested by San Joaquin County Health, WEGE tried to coordinate the 41' Quarter Sampling Event with AGE in order to obtain same day groundwater gradient and contaminant concentration data for both sites (1856 & 1876 Country Club Boulevard) AGE had already performed the 4'' Quarter 2001 monitoring of 1856 Country Club Boulevard, but had scheduled the 1" Quarter 2002 monitoring for January 15, 2002 Mr Michael Infurna, San Joaquin County Health approved waiting until January 15, 2002 to perform the site monitoring No sampling/monitonng of 1876 Country Club Boulevard site occurred during the 4h Quarter 2001 is'r QUARTER 2002 SITE ACTIVITIES i Groundwater samples were obtained from all wells dunng this quarter (Janaury 15, 2002) As scheduled AGE also obtained samples and groundwater measurements from the wells associated with Country Club Food and Fuel, 1956 Country Club Boulevard Figure 3 - Site Base Map has been expanded to show the relative positions of the Country 4 QM 4a` 2001&1-5' 2002