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10 <br /> i January 2001 <br /> AGE-NC Project No 96-0254 <br /> Page 5 of 6 <br /> I4.0. SUMMARY AND CONCLUSIONS <br /> Based on the data collected during this monitoring period, AGE concludes <br /> A pumping rate of 1 0 m produced a maximum drawdown of approximately 2 89 feet in <br /> ' P p g � p Pp Y <br /> MW-1B after 330 minutes of pumping A maximum drawdown of approximately 0 15 feet <br /> was observed in MW-1A after 264 minutes of pumping The transmissivities for wells <br /> MW-lA and MW-1B were calculated to be 293 gal/day-ft and 6,769 gal/day-ft,respectively <br /> I Due to the proximity of MW-lA and MW-1B the transmissivities calculated may be more <br /> representative of aquifer properties than horizontal transmissivities The storativity for <br /> MW-lA was calculated to be 0 78 (unitless) Storativity cannot be calculated for MW-1B <br />' because it is the pumping well <br /> • A radius of influence could not be determined for this pump test due to the lack of drawdown <br /> observed in the surrounding wells, including MW-7 approximately 5 feet away from <br />' MW-1B <br /> • Due to low transmissivities and lack of observable drawdown in the surrounding wells, AGE <br /> I concludes that ground water extraction will not be an effective ground water remediation <br /> option at this site <br /> I • The depth to ground water at the site was encountered between 6 54 feet and 9 62 feet bsg <br /> The prevailing ground water flow direction at the site is generally northward with a low <br /> hydraulic gradient of 0 003 to 0 006 feet/feet <br /> I • Petroleum hydrocarbon-impacted ground water was encountered in samples from all of the <br /> monitoring wells with benzene concentrations exceeding the State of California maximum <br /> I contaminant level (MCL) of 1 ppb in every sample with the exception of MW-3 and MW-6 <br /> Petroleum hydrocarbon contamination was detected in well MW-2A for the first time in the <br /> last five quarterly monitoring events and in well GLMW-3 for the first time in the last nine <br /> I monitoring events However, data acquired from a monitoring event on 19 December 2000 <br /> from the adjacent site 2420 Grant Line Road indicated that none of the analytes were <br /> detected above laboratory reporting limits in GLMW-3 The analytes detected in MW-2A <br /> Iand GLMW-3 during the 17 October 2000 monitoring event could possibly be attributed to <br /> cross-contamination due to poor decontamination procedures <br /> I <br /> 5.0 RECOMMENDATIONS <br /> Based on the results of this investigation, AGE recommends the next quarterly monitoring event <br /> • should be scheduled for January 2000 <br /> I <br /> Advanced GeoEnvironmental Inc <br /> I <br />