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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 1 and Figures S 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. It also included the completion of three cluster wells R1 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 hydrogeolognc 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 fixture remediation efforts 3RDOUARTER 2001 SITE ACTBj TIES Groundwater samples were obtained from all wells during this quarter (August 21, 2001) Field notes from site monitoring and sampling can be found in Appendix A DEPTH TO WATER MEASUREMENTS Depth to water was measured at all wells on August 21, 2001 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 COLLECTION AND CERTIFIED ANALYSIS OF GROUNDWATER SAMPLES WEGE and Pittman Well Purging (PWP) personnel collected quarterly groundwater samples from the eleven monitor wells at the site on August 21, 2001 See Appendix A for QA/QC, details, methods, procedures, abbreviations, and acronyms used in sampling and analysis 4 Sanchez 3rd QM 2001