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Mr Sam Savig Page 5 of 6 • 3.2 Soil Analytical Results TPHk, TPHg, ethylbenzene and xylenes were detected at concentrations of 42 ppm, 130 ppm, 0 62 ppm, and 2 0 ppm in boring MW 1 at a depth of 10 feet bgs TPHg, benzene, ethylbenzene and xylenes were detected at concentrations of 29 ppm, 0 005 ppm, 0 012 ppm, and 0 030 ppm in boring MW3 at a depth of 25 feet bgs No other petroleum hydrocarbon constituents were detected in any other soil sample analyzed from the three borings Total lead ranged from <5 0 ppm to 8 8 ppm Soil analytical results are summarized in Table 2 Laboratory reports and chain of custody documentation are included in Appendix E 3.3 Groundwater Analytical Results Low levels of gasoline constituents were detected in each site well Well MW 1 contained TPHg, benzene, toluene, ethylbenzene, and xylenes at 690 parts per billion (ppb), 1 0 ppb, 0 9 ppb, 5 0 ppb, and 43 ppb, respectively Well MW2 contained TPHg, ethylbenzene, and xylenes at 180 ppb, 1 2 ppb, and 3 0 ppb, respectively Well MW3 contained TPHg, benzene, toluene, ethylbenzene, and xylenes at 830 ppb, 0 6 ppb, 0 7 ppb, 19 ppb, and 46 ppb, respectively No TPHd, TPHk, oxygenated gasoline additives, or lead scavengers were detected in any site well Groundwater analytical results are summarized in Tables 3 and 4 Laboratory reports and chain of custody documentation are included in Appendix D 4.0 SUMMARY • Three groundwater monitoring wells (MW1, MW2, MW3) were installed to a depth of approximately 25 feet bgs to further investigate the extent of soil and groundwater contamination at the site Shallow'soil beneath the site consists primarily of sand and silty sand with some silty clay layers Relatively low levels of gasoline and kerosene constituents were detected in soil samples collected from well MW 1, and low levels of gasoline constituents were detected in soil samples collected from well MW3 No soil contamination was noted in well MW2 First groundwater was initially found at depths ranging from approximately 8 to 12 feet bgs during drilling and stabilized at a depth of approximately 11 5 feet bgs in site wells Groundwater flows in a north-northeasterly direction with a flat gradient of 0 0008 feet per foot The estimated groundwater velocity beneath the site is approximately 15-20 feet per year Shallow groundwater beneath the site has relatively high TDS levels According to information available on the GeoTracker database maintained by the State of California, the nearest known water supply well is an inactive well at the City Corporation Yard, located approximately 1,000 feet south (up-gradient) of the subject site Groundwater analytical results indicate that petroleum hydrocarbon contamination is present in groundwater at relatively low levels Low levels of TPHg were detected in all wells Benzene concentrations detected in wells MW1 and MW3 did not exceed the State Maximum Contaminant Level (MCL) for drinking water No benzene was detected in well MW2 No diesel, kerosene, or . gasoline additives were detected in any site wells G1Data1GROLJNDZEITHORPE1Souza\Reports\WELLRPT doc