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1 <br />' 29 January 1996 <br /> AGE-NC Project No 95-0143 <br />' Page 3 of 6 <br />' Analytical, Inc (MAI) in Pacheco, California Selected samples were analyzed for total petroleum <br /> hydrocarbons as gasoline (TPH-g) and volatile organics (benzene, toluene, ethylbenzene and total <br /> xylenes, BTE&X) in accordance with EPA methods 8015m and 8020, respectively <br /> 1 <br /> 3 2 LOGGING <br />' Soil was extruded from om the second brass sleeve and screened for the presence of organic vapors using <br />' a PID, and the readings were recorded on the boring logs The soil was then described in accordance <br /> with the Unified Soil Classification System (see Appendix A -Bol ing Logs) <br /> 33 WELL COMPLETION <br /> Each boring was completed as a ground water monitoring well using 20 feet of 2-inch diameter PVC <br /> casing with 0 020-inch screen Blank PVC casing was then extended to the surface The filter pack <br /> (#3 Lonestar sand) was installed from total depth to two feet abo-Ve the screen interval Bentonite <br /> pellets were used to make a 2-foot plug in the annular space immediately above the sand filter pack <br /> in each well and the wells were then grouted to the surface with Portland Cement <br /> 34 <br /> MONITORING WELL PURGE PROCEDURES <br /> On 5 October 1995, a Solinst water level meter was used to measure the depth to ground water in <br /> each well relative to the top of the casing Free product was encountered in MW-3 and the thickness <br /> was measured using an Ullage interface probe The relative ground water elevations and hydraulic <br /> gradient were determined from these data (Table 1) <br /> Monitoring wells MW-6, MW-7, MW-9 and MW-10 were then purged using a 2-stage submersible <br /> purge pump The pump was decontaminated prior to purging each well using an Alconox solution <br /> A minimum of three well volumes of water was evacuated from each well to stabilize well parameters <br /> Approximately 6 to 10 gallons of water were removed from MW-6, MW-7 and MW-10, <br /> approximately 45 gallons of water were removed from MW-9 Temperature, pH and conductivity <br /> were measured at regular intervals using an ICM model 52200 water analyzer <br /> On 20 November 1995, the <br /> depth to ground water and product thickness was measured in each well <br /> P <br /> relative to the top of the casing (Table 1) Monitoring wells MW-14, MW-15, MW-16 and MW-17 <br /> Iwere then purged of approximately 10 gallons of water following the procedures described above <br /> All purged water was stored in 55-gallon DOT drums on-site Stabilization data and field logs are <br /> included in Appendix B <br />