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_ R`spona Marketuarterl Re ort Vertical Groundwater Investigation&November 2043 Quarterly P Page: 7 i Table of Laborator Water Sam le Results (12- -03 Ox enates Sa le LD. Gasoline Benzene Toluene E-OB3 nzene XOleenes 0 g mtae 1 X0.05 X0.3 X0.3 MWA Gasoline reported in MgIL BTEX and Oxygenates inµg11- ND--Non Detect NA=Not Analyzed, i 1 Y GROUNDWATER MONITORING Prior to the installation of MW-4, UTEgx, g product and the three existing groundwater-monitoring wells were monitored theowells.tl Each well was depth to groundwater measurements obtained before Purg means of a steam-cleaned, stainless steel evacuated of at least three well volumes by bladder-type pump. During the purging of he wells, field pH, electrical conductivity, ` and temperature measurements were monitored to verify well stability and to insure that well stability was achieved, representative groundwater samples were collected. Once . r groundwater samples were collected. All field data sheets are presented in appendix i les were labeled and placed in an ice chest cooled with blue ice or �I The groundwater same crushed ice, logged on a Chain of Custody form, and delivered to GeoAnalytical r California. The water Laboratories, Inc., a state certified laboratory, located in Modesto enated Compoundscluding i samples were analyzed for BTEX, MTBE and the oxygenated EDB and 1,2 DCA (EPA Method 8260B) and gasoline range petroleum hydrocarbons (EPA Method 5030, GCFID). All of the water samples were checked in the laboratory for dissolved oxygen concentrations by Method SM4500-0 G. SUMMARY FINDINGS Groundwater was present as an unconfined state at depths of approximately 25.85 to 26.37 feet below ground surface at the Ripona Market site on November 26, 2003. The unconfined water table was present approximately 0.18 to 0.38 feet higher than in the August 4, 2003 monitoring event. The groundwater level for the deep boring is very similar to the levels in the shallow wells suggesting that the wells are screened in a . in Figure 7ydrograph of the groundwater common aquifer and a vertical gradient is not present. A elevations at the Ripona Market site is presented Shallow groundwater flow on November 26, 2003 was North 62.5 East with a gradient of 0.008 ft/ft similar to past monitoring events. The groundwater elevations and groundwater flow direction are shown on Figure 5. Groundwater Flow. Groundwater Elevations 11-26-03 � Weil lCollar Elevation DTIN GW Elevation MW-1 63.28 25.85 37.43 M\/V-2 63.59 26.13 37.46 MW-3 63.8 26.37 37.43 MW-4(19IBI03) 63.52 25.89 37.63