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• , S i 12 May 1995 AGE-NC-95-0121 ,Page 3 of 4 3 2. COLLECTION OF GROUND WATER SAMPLE'S _ Ground water samples were collected from each well using new disposable bailers The samples were ' collected in 40-m1 EPA vials preserved with hydrochloric acid and one-liter amber bottles and were transported in a chilled container to ABC Laboratories, Pan-Ag Division (Pan-Ag) in Madera, ' California The samples were analyzed for TPH(gasoline and diesel)and BTE&X in accordance with EPA methods 8015m and 602, respectively 3 3. GROUND WATER DEPTH On 23 May 1995,the depths to ground water were measured relative to the top of the casing, using ' a Solinst water level meter, in all nine wells at the site Pressure was noted in several wells when the locking caps were removed Ground water was allowed to stabilize in these wells before ' measurements were collected The ground water elevations in'each well and hydraulic gradient were calculated by subtracting the depth to ground water from the'surveyed casing elevation (Table 1) A disposable bailer was used to deternune the apparent thickness of free product in MW-1 ` 4.0. FINDINGS , I 41 RELATIVE GROUND WATER ELEVATION AND GRADIENT k ' The ground water elevation in each well was calculated by subtracting the depth to water from the surveyed casing elevation(Table 1) Ground water elevation at the site ranges from -18 77 t 29 ' feet, indicating an average rise of 6 35 feet between December 1994 and May 1995 Ground water flow direction was determined to be northeast(Figure 3) A mounding effect was noted ' near the southwest corner of the property The ground water gradient was determined to be, approximately 0 0025 ft/ft This gradient is slightly more shallow than the gradient calculated in December 1994 No free product was observed in MW-I that would effect ground water depth measurements, only a sheen was observed A2 ANALYTICALaRESULrTS OF GROUND WATER SAMPLES TPH-as gasoline` was detected in samples from,MW-1 through MW-4, MW-6 and MW-7 at concentrations`from 1,600 pg/1(parts per billion ppb,MW-2)to 11,000 ppb (MW-1), TPH as diesel was detected in samples from MW-I through MW-6 and MW-9 at concentrations ranging from 72 ppb (MW-1) to 8,I00 ppb (MW-5) The laboratory report noted that the chromatograms from the