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Pil^C 4,(ell«:, i niLkmg 2ij i),J] <br /> to bailinu and sampling Slightly more than three well volumes of water (1 1 to 14 gallons) ,were <br /> purged from each and stored in a 55-gallon drum near MW-1 A Corning meter was used to <br /> measure temperature, conductivity, and pH during purging to confirm that these parameters <br /> stabilized before sampling(Appendix A) Tlie purging and sampling ecluipinent 4vas <br /> decontaminated with "I'Sl' Solution between wells <br /> Water saijiples were collected in disposable plastic bailers and placed in sterilized 40-ml vials and <br /> 1-liter amber Bottle:~ 1 he ~ample,, were placed in a plastic cooler, iced, and %hipped the: same day <br /> to McCampbell Analytical in Pacheco, California for analysis 'I he samples were received by <br /> McCampbe;ll on .lanuary i b and analvzed for TI'l1-gasoline, TPH-diesel, and 31 lex on Janllary <br /> 16 and 17 <br /> 5.0 RESULTS <br /> 5.1 Grousidwatcr Gradient and Flow Direction <br /> Depth-to-broundvvater measurements and calculated groundwater elevations are presented in Tattle <br /> 1 Results from previous monitoring events are included for comparison <br /> A continuous rise in the elevation of the pierometric surface since September is evident `l his rise <br /> is due to the seasonal increase in rainfall <br /> As in the previous months, the elevation of the piezometric surface is nearly identical in all three <br /> monitoiing wells, precluding reliable conclusions regarding groundwater flow direction However, <br /> the lanuary data are consistent with that from November and December, suggesting that <br /> groundwater flow i,, to the south (f igure~ 3) <br /> In an attempt to obtain additional groundwater information in the vicinity of the site, Upgradient <br /> contacted Mr Sasson regarding nearby sites Mr Sasson informed Upgradient that PHS/El ID <br /> tiles contain no other inibrmation on the direction of groundwater flow in the area <br /> 5.2 Groundwater Contamination <br /> Groundwater samples obtained in January indicate that groundwater contamination has shifted to <br /> the east slightly since September TPH-g and TPH-d concentrations in the western well (G 1 -2) <br /> have decreased from 930 ug/l and 950 ug/1 respectively to 64 ug/l and 400 ug/l, while; <br /> concentrations in the eastern well (GT-1) have increased from ND and 80 ug/1 respectively to 550 <br /> ug/l and 960 ug/l In addition, TPH-d was detected in MW-1 at a concentration of 96 ug/l <br />