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' 01 April 2004 . AGE-NC Prod ect No 97-0301 ' Page 3 of 6 ' 3.0. FINDINGS Ground water elevation, flow direction and gradient were determined from field data collected ' on 12 November 2003 The contaminant Impact to groundwater was quantified by the groundwater laboratory data 3 1 GROUND WATER ELEVATION AND GRADIENT ,tig �o ' The depth to ground water measurements at wells MW-1,MW-2 and MW-5 through MW-12 vaned between 33 78 feet(MW-9B)and 35 55 feet(MW-8C)below the topf well casingsground water elevation was calculated to be between 2168 feet(MW-SA)and 22 8Jfeet(MW-12below mean ' sea level (MSL) Generally, ground water elevation at the site decreased an average 0 26 feet between the September 2003 and the November 2003 ground water monitoring events ' Groundwater elevation data collected on 12 November 2003 from wells MW-8(A-C),MW-9(A-D) and MW-12 (A-D) was depicted on cross section D-D' (Figure 3) By determining the difference between ground water elevations(dh)and dividing by the difference of the screen interval midpoints ' (dl),the vertical gradient between adjacent screen Intervals was calculated Generally,very steep to moderately steep downward vertical gradients were observed between the First and Fourth Water ' Zones (Figure 3) However, a steep upward gradient was observed at well MW-12 between the Second Water Zone and the Third Water Zone, and a nearly flat,very slight upward vertical gradient was observed between the First Water Zone and the Second Water Zone 7 ' The ground water elevation at wells MW-1,MW-2 and MW-5 through MW-12 were calculated by subtracting the measured depth to ground water from the surveyed casing elevation The November ' 2003 ground water elevation data collected from the site was plotted for the First Water Zone (Figure 4) as defined In AGE's CPT Site Investigation - Third Quarter 2001 (dated 25 October 2001) D,11 1 v�d•l�`6T 3 2 LABORATORY RESULTS OF GROUND WATER SAMPLES ' A total of twenty-four (24) ground water samples were submitted to Cal Tech Environmental Laboratories, a DHS-certified laboratory, for analysis ' TPH- was detected in three water samples collected from wells MW-1, MW-5 and MW-7 at g p concentrations of 4,200 micrograms per liter (µg11), 9,800 µg/1 and 6,800 µg/1, respectively The ' estimated extent of dissolved TPH-g In First Water Zone Is depicted In Figure 5 For the second . consecutive quarterly monitoring event,TPH-d,TPH-k and TPH-mo were not detected In any of the J ' Advanced GeoEnviron mental,Inc