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all wells associated with this site, see Appendix B. Figure 3 has been revised to this new survey along with Table 1. All associated figures showing site conditions are based on the new Figure 3. The property previously contained two 1000 gallon gasoline Underground Storage Tanks (UST's), product dispensers, and associated underground piping (Figure 3). The UST's, dispensers, and piping were removed from the site in 1989. Over-excavation of gasoline contaminated soils associated with the USTs and former pump islands occurred during the month of February 2003, removing an estimated 638 tons of gasoline contaminated soils from above and below the water table (maximum depth of excavation 30 feet below surface). The property owner originally installed five onsite monitoring wells. Three additional cluster wells and four piezometers were installed to aid in the investigation of soil and groundwater conditions at the site. Prior to over-excavation monitor well MW 1 was destroyed by over drilling and during excavating cluster wells RIA and R 1 along with piezometers PZIA,PZ1B,PZ2A and PZ2B were removed by excavating, removing all well materials. MW2, MW3, MW4, MW5, MW6A, MW613, MW7A and MW7B are currently active wells.. LOCAL GEOLOGY AND HYDROGEOLOGY The site is located on surface soils belonging to the Stockton Adobe Clay and Honeycut Clay series. They are derived from Recent alluvial fan and floodplain deposits. The 40 feet of explored section consisted of clay and silt overlying interbedded lenses of silty and clayey sands below 12 feet. This first sandy formation has been designated the A zone aquifer. The base of the A zone is 17 - 18 feet below ground surface(bgs). A 3 to 4 feet thick silty clay separates the silty clayey sand A zone aquifer from the 6 to 7 foot thick B zone aquifer that is found at approximately 21 feet bgs. 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 at least 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). MWI 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. 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. 3 Sanchez WORKPLAN 9-03