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Project No 58080-06-03 <br /> January 19, 1996 <br /> ' Page 3 <br /> ' pumping de-ionized water through the purge pump into a VOA vial after sampling the last <br /> well and performing pump decontamination <br /> ' Laboratory nalysis <br /> The groundwater samples collected on December 14, 1995 were delivered to Sparger, a <br /> California certified analytical laboratory, for the analyses of total petroleum hydrocarbons <br /> as gasoline and diesel (TPHg and TPHd) following EPA Test Method 8015 modified, <br /> benzene, toluene, ethylbenzene and total xylenes (BTEX) following EPA Test Method 8020 <br /> and methyl tert-butyl ether (MTBE) following EPA Test Method 8240 The laboratory <br /> reports and chain of custody documentation are attached <br /> ' FINDINGS <br /> Groundwater Elevations and Gradient <br /> A review of the last reported groundwater level measurements performed in September <br /> 1995, indicates that groundwater levels have risen an average of 1 8 feet in the last three <br /> months to depths ranging from 5,1 7 to 54 2 feet below TOC The direction of groundwater <br /> flow beneath the Bokides site appears to the south-southeast The groundwater flow <br /> ' direction transitions from south-southeast to south-southwest beneath West Lodi Avenue <br /> and the Togo's site The groundwater gradient was calculated to be 0 003 ft/ft and is <br /> consistent with flow directions evaluated from previous measurement events <br /> Analytical Results <br /> ' A cumulative summary of groundwater analytical data is presented on Table II TPHg was <br /> detected in each of the five FDIC wells and the two Bokides wells at concentrations ranging <br /> from 71 to 1,200 ug/L The highest TPHg concentration was detected in well BMW-1 <br /> ' located within the Bokides site, adjacent to existing underground storage tanks Benzene <br /> was detected in each of the five FDIC wells and the two Bokides wells at concentrations <br /> ranging from 29 to 120 ug/L The highest benzene concentration was detected in well MW- <br /> 2 located within the Togo's site D-eA&-- -M MTBE concentrations ranged from 35 ug/L <br /> (MW-3) to 700 ug/L (MW-1) TPHd was not detected man of the wells sampled <br />' TPHg, BTEX and MTBE were not detected in trip blank sample TB-1 TPHg, BTEX and <br /> MTBE Were detected in equipment blank sample EB-1 The presence of TPHg in sample <br /> EB-1 at a concentration higher than any of the wells sampled with the pump (wells MW-1 <br /> through MW-5 only) suggests that decontamination water remained in the pump at the time <br /> of equipment blank sample collection <br /> 1 <br />