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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 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 I and Figures 8 and 9 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 MW1 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 And 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 monitor wells MW6 A&B and MW7 A&B to evaluate the A and B zone aquifers and future remediation efforts 2N1° OUARTER 2001 SITE ACTIVITIES On February 12 - 15, 2001 five "Geoprobe" direct push borings were performed along the southern gutter area of Country Club Blvd (P-8 and P-9) and along the western gutter area of Mission Road (P-10, P-11 and P-12) west and downgradeint of the site Data results from these probes were used in the decision to install cluster A and B zone wells Six newly installed wells (clusters MW6 A & B, MW7 A & B and RI A & B) were developed on April 13, 2001 Groundwater samples were obtained from all wells during this quarter (April 18, 2001) The findings from the probes and installation of cluster wells MW6, MW7 and R1 are presented on borehole logs, Appendix B and Figures 8 and 9 SAMPLE BORINGS PS - P12, FEBRUARY 14-15, 2001 Prior to installing additional groundwater monitoring wells, five geoprobe direct push sample borings were performed These borings were necessary to A) determine the lateral extent of groundwater contamination and B) develop the proper well design to allow representative sampling and evaluation of the hydrocarbon plume groundwater transport 5 Sanchez 2nd QM 2001