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tours site based on Figure 6 presents a map of groundwater elevation This map displaysttl-eepresence of a water level elevations in each of the seven w In the low point or trough at the western edge of the site andranraiativ lflat area direction of the site. Based on interpretation of this map, the primary groundwater is west-southwest from the former tank locations toward the western a agdeeo of the a Site,i is a lesser flow component toward the south. The southwesterly gradient direction as essentially opposite to the regional northwesterly g map defined by the San Joaquin County Flood Control and Water Conservation Districtcy ae the "Lines of Equal Elevation of Water in WP4s, Spring 1990•'� This orrecharging areas. result of local artificial gradient influences such aspumping Another possible gradient influence is daily tidal flux due to the proximity of the Stockton deep water channel to the north of the site. 3.0 ANALYTICAL RESULTS ed in Table 1. The complete analytical report is presented Analytical results are summariz in Appendix B. 3.1 c the soil A single soil sample from the capillary sample w s taken from a depth of approe was collected from each ximately ximately borings prior tc well construction. Each s p ten feet below the ground surface. Soil samples were analyzed for BTEX, pound and total lead. The analytical results indicate the presence 0 e were completed as monitoring ng wells MW-4, lead in all four of the soil borings (the boring lane were MW-5, MW-6, MW 7). Of the four BTEX compounds, only toluene and er million, detected. Borings 4, 5, 6 and 7 contained 37, 5.3, 1.9 and 1.6 mg/Kg (parts ppm) of toluene, respectively. Borings hylbenzene wad 7 s notddetected n any of nd 2.4 hje soil xylene, Kg of ospectively. Benzene samples. Xylene Was not detected contained 16 5�7 W9 6 and 8.0 mglyg of total leadas not detecAed in any of the ` samples. Borings 4, 5, respectively. 3.2 Groundwater samples were analyzed for BTEX and TPFi-G. Of the seven wells sampled, entratne only the sample from MWA exhibited detectable eonc zen 500 uglL of xylene ans of the analytes. d sample contained 1600 uglL (parts per billion, ppb) of ben 16 ugiL of TPH-G. 3.3 -- Sample MW-5, the blind duplicate of MW-1, slowed 1700 uglL, 610 uglL and 14 uglL of _ ctabe sam , benzene, xylerie and TPFi-G,-respectivel which is_an ecce #able_analytical duplication. Sample MW-9, the equipment uecontam en decontamination procedures showed nov were hol ough.BTEX- concentrations — - -- indicating the eq p - 10 -