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k <br />' 31 January 2002 <br />' AGE-NC Project No 95-0128 <br /> Page 5 of 8 <br />' An intercept of the no influence edge of the semi-loganthrmc plot of draw-down m-observation wells <br /> versus distance from the exti action point equals 100 feet the distance commonly thought of as the <br /> radius of influence (Appendix F) Utilizing the parameters noted above and site specific <br />' characteristics, AGE calculated that the extraction wells pumped at five gallons per minute would <br /> have a capture zone extending five feet down gradient, eight feet in each cross gradient direction, <br /> expanding up to fifteen feet in each direction perpendicular to the flow direction approximately, <br />' seventy-five feet up gradient from the pumping well Figure 3 shows the calculated capture zone for <br /> well EW-1 Calculations are shown in Appendix G <br /> 3 2 EXTRACTED WATER SAMPLING PROCEDURES <br />' Approximately 4,100 gallons ofpurged water were generated during the pump test During the pump <br /> test, two sets of a grab samples were collected prior to discharge into the tank utilizing three 40-m1 <br /> EPA-approved volatile organic analysis (VOA) vials containing 0 5 ml 18% hydiochlonc acid as a <br /> sample preservative The samples were collected at 1 30 prri(5 hour interval) and at the termination <br /> of the test 7 00 pm(12 hour interval ) <br /> lie Following sample collection, each preserved sample was logged on a chain-of-custody form,placed <br /> in a chilled container and transported to a California Department of Health Services(DHS)-certified <br />' laboratory for analysis foi <br /> • Total petroleum hydrocarbons quantified as gasoline and diesel (TPH-g and TPH-d, <br /> respectively) by EPA Method 8015 Modified, and <br /> • Benzene, toluene, ethylbenzene and xylene(BTEX) and methyl-tertiary butyl ether(MTBE) <br /> by EPA Method 8020 <br />' 3 3 ANALYTICAL RESULTS OF EXTRACTED WATER <br /> The 1 esults of the laboratory analysis of the two extracted ground water samples included TPH-g <br />' ranging from 22,000 rnrcrograms per liter([ig/1) up to 26,000 dug/l BTEX compounds were detected <br /> at concenti ations as high as 3,900 �ig/l(benzene) Analytical results of samples are summarized on <br /> Table 3 The laboratory reports (McCampbell Analytical Inc Lab I D 81657 to 81658), Quality <br /> Assurance and Quality Control data and chain-of-custody forms are presented in Appendix H <br />' 3 4 PURGED GROUND WATER DISPOSAL <br />' On 31 October 2001, the ground water extracted during the pumping test was pumped from the <br /> Advanced GeoEnvironmental Inc <br /> f <br />