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CLEARWXTER <br /> G R O U P 1 N c <br /> 3 0 FIELD ACTIVITIES <br /> All field work was conducted according to Clearwater Field Proceedures (Appendix <br /> A) which are consistent with both local and state guidelines Prior to sampling, each <br /> monitoring well was gauged to the nearest hundredth of a foot The wells were <br /> then purged of at least three well casing volumes until purging parameters <br /> stabilized or until the well went dry Monitoring well purge/sample data sheets are <br /> included as Appendix B <br /> rGroundwater samples were collected from all five monitoring wells Each <br /> groundwater sample was collected with a disposable polyethylene bailer and was <br /> transferred to sample containers appropriate for the required analyses Sample, <br /> containers were labeled and placed in a cooler A chain-of-custody was prepared and <br /> accompanied the samples to the laboratory Groundwater sample analysis was <br /> performed by PACE, Inc , DHS-certified laboratory located in Novato, California All <br /> groundwater samples were analyzed for total petroleum hydrocarbons as gasoline <br /> (TPHg) by EPA Method 8015 (modified), and for benzene, toluene, ethylbenzene and <br /> total xylenes (BTEX) by EPA Method 8020 (modified) <br /> 4.0 RESULTS <br /> 4.1 Water Level Monitoring Data <br /> The depth to groundwater in the monitoring wells ranged from 26 41 to 27 01 feet <br /> below ground surface (bgs) on December 21, 1994 The depth to groundwater was <br /> measured from the survey mark on top of each well casing Groundwater <br /> elevations are presented on Table 1 Groundwater elevation contours are presented <br /> on Figure 3 The local groundwater flow direction was calculated to be towards the <br /> east at an approximate gradient of 0.8% The groundwater flow direction and <br /> gradient is consistent with results obtained during the previous monitoring events <br /> 4.2 Ground Water Analytical Results <br /> All analytes tested for were detected in groundwater samples collected from MW-1, <br /> MW-2, MW-3 and MW-4 None of the analytes were detected in concentrations <br /> exceeding method detection limits in groundwater sample collected from MW-5 <br /> The detected concentrations of benzene ranged from 0 6 ppb in the sample collected <br /> from MW-1 to 400 ppb in the sample collected from MW-4 A summary of <br /> analytical results is presented on Table 1 Hydrocarbon concentrations are shown on <br /> D-103 QMR 2 February 2, 1995 <br />