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I BACKGROUND bgs. Orme additional US ] was identified south of the USTdinewcoed in July. Soil observed at the other baring locations appeared to be mmdisturWd native soil. In January 2010 seven 10-inch diameter Wrings were excavated at the UST area using an air knif and vacuum truck to determine the sin and number orthe tanks and their location with respect to the street and building. One additional US I was encountered and another location was inferred based on the spacing ofthe woks for a total of four USTs. In September 2010 GEMS Environmental Management Services, I=. removed four 600 gallon single walled steel USTs located beneath the sidewalk along South Saner Shunt. 'Ilie US'I'a were partially filled with sand. Two soil samples were collected form beneath each U%T from the center and west end of the tanks and submitted for laboratory analyses. Soil samples were not collected from the cost ends ofthe banks due to me potential of damaging a fiber optic utility located beneath the border USTs. The soil sample collected from the southern UST contained 3.2 mglkg total petroleum hydrocarbons as diesel (WF dk all other torgekd armlyws were not detected. The UST pit was beckfmlled and compacted with clean soil. In December 2010 groundwater mormoring well MW-10 was installed a the location of the recently removed USTs along South Sumer Street and near well M W-2. The well was installed to determine the vertical extent of petroleum hydrocarbons in soil and assess petroleum hydrocarbon contamination in draper groundwater lrncath the Site. Four soil samples submitted for laboatory analyses were collected from 30, 70, 90, and I10 feet bge. Soil samples collected hom the Wring for MW-10 contained 1.9 mg/kg WIT gf a sampling depth of l 10 feet.No other soil samples collected from the boring contained detectable concentrations ofTPH-g. Bennne was detected in team soil samples at concentrations of 12 pg/kg and 22 gg/kg from 30 and I10 feet bgs, respctively. Groundwater samples collected in January 2011, shortly after the well was installed, contained 1,500 pg/L 'ITH-g and 15 pg/L Wmnnc. Subsequent groundwater dwater sampling of the well yielded lower contaminant concentrations. Groundwater samples collected during the November 2012 sampling event conminod 0.87 pg/1, bcro me, 0.70 pgd. toluene, 0.6 pg/L ethyl berme, and 0.58 gg/L toil xylenes.