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1 <br /> f 1 <br /> 22 July 1996 _ <br /> AGE-NC Project No 95-0111 <br />' Page 2 of 3 - <br /> petroleum hydrocarbons quantified as gasoline and diesel (TPH-g and TPH-d), volatile aromatics <br />' (benzene, toluene, ethyl benzene and total xylenes BTE&X) and methyl-tert-butyl ether (MTBE) <br /> in accordance with EPA methods 5030/8015m,,5030/8015m, 602 and 602, respectively <br /> 1 , <br /> 3.0. FINDINGS <br />' 3 1 GROUND WATER FLOW DIRECTION AND GRADIENT <br />' The relative elevation of ground water in each well was calculated by subtracting the ground water <br /> depth from the surveyed casing elevation(Table 1) All wells were surveyed relative to MW-1, MW- <br /> 1 was assigned an arbitrary casing elevation of 20 feet <br /> 1 1 <br /> The relative ground water elevation ranges from 9 74 feet in MW-1 to 6 48 feet in MW-4 Ground <br />' water elevation decreased an average of one foot at the site between March and Tune 1996 Free <br /> product thickness was not measurable in MW-4 nor MW-5, however a sheen was observed in each <br /> well <br /> Ground water flow direction in the area of the site is northeast Ground water gradient at the south <br /> end of the site is approximately 0 005 ft/ft The gradient steepens towards the north end of the site <br />' to 0 014 ft/ft Ground water surface elevation is depicted in Figure 3 - Relative Ground TI'ater <br /> Elevation <br />' 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES <br />' TPH-g was detected in samples collected from MW-4 and MW-5 at concentrations of 420 µg/l <br /> (micrograms per liter or parts per billion ppb) and 460 ppb, respectively TPH-d was detected in <br /> samples from MW-2, MW-4, MW-5 and MW-6 at concentrations up to 38;000 ppb (MW-4) <br />' Laboratory notations for the samples fiom MW-4 and MW-5 indicated the presence of free product <br /> Benzene was detected in samples collected from MW-1, MW-2, MW-4 and MW-5 at concentrations <br /> up to 94 ppb, ethyl benzene and xylenes were detected in samples from MW-2 and MW-5 at <br /> concentrations up to 113 ppb Toluene was not detected in any of the water samples collected at the <br />' Site <br /> MTBE was detected in samples from MW-1 and MW-6 at concentrations of 61 and 6 4 ppb, <br /> respectively, MTBE is MW-6 was confirmed by GC/MS, in accordance with a FHS-EHD request <br /> Analytical results of ground water samples are summarized in Table 3 The laboratory report (MAI <br /> Laboratory Nos 62283 to 62288) and chain-of-custody are included in Appendix D <br /> t Y <br />