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I ' 26 June 2002 AGE-NC Project No 95-0143 ' Page 2 of 4 ' 2 2 COLLECTION OF GROUND WATER SAMPLES Prior to the collection of ground water samples, the depth to ground water was re-measured in each ' well to ensure that a minimum of 80% of the initial water volume had recharged Water samples were then collected from the wells using disposable bailers Upon retrieval, the samples were transferred into 40-m1 EPA-approved VOA vials containing 0 5 ml 18% hydrochloric acid as a I sample preservative The samples were labeled and transported under chain-of-custody, in a chilled container,to McCampbell Analytical,Inc (MAI),a DHS-certified laboratory,and were analyzed for ' • Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA Method 8015 modified, and ' • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tertiary-butyl ether (MTBE) in accordance with EPA Method 8021 B ' 3.0. FINDINGS '! Ground water elevation was calculated and flow direction was inferred from field data, the hydrocarbon impact to ground water was quantified from laboratory analysis 3 1 GROUND WATER ELEVATION AND GRADIENT The elevation of ground water in the twelve wells was calculated by subtracting the depth to water from the surveyed casing elevation (Table 1) During the May 2002 monitoring event, the average ' depth of ground water was 16 1 feet bsg, the average ground water elevation was approximately 6 63 feet below mean sea level (MSL), a decrease of 0 19 feet since the February 2002 monitoring event The approximate flow direction was toward the northeast with a gradient of 0 001 feet/feet at ' the site, ground water elevation contours for the May 2002 monitoring event are illustrated in Figure 3 Ground water was within the screened intervals of MW-16,MW-17,MW-22,MW-23 and MW-24 Ground water ranged from 0 08 feet to 6 69 feet above the screened interval in the other seven monitoring wells 32 ANALYTICAL RESULTS OF WATER SAMPLES During the May 2002 monitoring event,TPH-g was detected in samples collected from monitoring . wells MW-3, MW-6, MW-7, MW-9 and MW-22 at concentrations ranging from 96 gg/l (MW-9) Advanced GcoEnviron mental,Inc