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<br /> Third Quarter 2005 Quarterly Groundwater Monitoring Report
<br /> Raymond Investment Corporation,Stockton,CA
<br /> Page 2
<br /> (. GROUNDWATER ELEVATIONS AND GRADIENT
<br /> � J
<br /> The average groundwater elevation in the monitonng wells was -18 50 feet, a decrease of approximately
<br /> 0 01 foot (0 01 foot lower in elevation) since the previous sampling event conducted on May 4, 2005 The
<br /> estimated groundwater gradient for the Site was 0 0045 ft/ft to the east-northeast and is shown on Figure
<br /> 3, attached Monitoring well groundwater elevation data are presented in Table 1, below Historic
<br /> groundwater elevation data are presented in Table A, attached
<br /> Table 1
<br /> Groundwater Elevation Data (August 16, 2005)
<br /> Well I D TOC Screened Depth to Groundwater
<br /> Elevation' Interval s Groundwater ElevationZ
<br /> MW-1 1635 32-47 3477 -1842
<br /> MW-2 1652 - 32-47 3501 -1849
<br /> MW-3R 15 78 - 32-47 3436 -18 58
<br /> TOC Elevation referenced to NAVE gKvertical datum V14 -t-q`0 y -
<br /> 3Groundwater Elevation Elevations are measured from the top of the well casings and are referenced to the benchmark indicated
<br /> above
<br /> All measurements are in feet
<br /> LABORATORY ANALYTICAL RESULTS
<br /> Groundwater samples collected from the monitoring wells were analyzed for benzene, toluene, ethyl
<br /> benzene, total xylenes (BTEX) and gasoline additives/oxygenates by EPA Method 826013, total
<br /> petroleum hydrocarbons quantified as gasoline (TPH-G) and total extractable petroleum hydrocarbons
<br /> quantified as kerosene (TEPH-K), motor oil (TEPH-MO), and diesel (TEPH-D) by EPA Method 8015M
<br /> Gasoline oxygenates/additives include methanol, ethanol, tertiary-butanol (TBA), methyl tertiary-butyl
<br /> ether (MTBE), di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether
<br /> (TAME), 1,2-dichloroethane (1,2-DCA), and 1,2-dibromocthane (EDB) Groundwater samples were
<br /> analyzed by Argon Laboratories, Inc of Ceres, California The current groundwater sample laboratory
<br /> analytical results are presented in Table 2, on the following page Historic groundwater monitoring data
<br /> are presented in Table A, attached
<br /> Table 2
<br /> Groundwater Sample Analytical Results (August 16, 2005)
<br /> Sample I D Sample Date B T E X TPH-G TEPH Oxygenates
<br /> (µg/L) (�Lg/L) (ug/L) (Ng/L) (ug/L) (µg/L) (µg/L)
<br /> MW1 8/16/05 <05 <05 <05 < 10 <50 <50-<250 <05—<50
<br /> MW2 8/16/05 <05 <05 <0 5 < 1 0 92* 82(D) <05-50
<br /> MW3R 8/16/05 <05 1 <05 1 <05 < 10 <50 <50-<250 <05—<50
<br /> Notes
<br /> *Chromatographic pattern does not match typical gas standard
<br /> Unit Conversions µg/L=micrograms per liter=parts per billion(ppb)
<br /> Analytical
<br /> B,T,E,x=benzene,toluene,ethyl benzene,total xylenes
<br /> TPH-G=total petroleum hydrocarbons,quantified as gasoline
<br /> TEPH=total extractable petroleum hydrocarbons quantified as kerosene(K),diesel(D),and motor oil(MO)
<br /> . Oxygenates=methanol,ethanol,tertiary butanol(TBA),methyl tertiary-butyl ether(MTBE),dt-isopropyl ether(DIPE),ethyl tertiary-bury]ether
<br /> (ETBE),tertiary-amyl methyl ether(TAME), 1,2-dichloroethane(1,2-DCA),and 1,2-dibromoethane(EDB)
<br /> $� CONDOR
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