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<br /> �j 3.0 LABORATORY ANALYSIS
<br /> ' The groundwater samples were transported to Severn Trent Laboratories, Inc. (STL), a state-certified
<br /> laboratory, located in Pleasanton, California. The groundwater samples were analyzed as follows:
<br /> ' - Well MW-I R was analyzed for the presence of TPH-G, MTBE, DIPE, TAME, ETBE, TBA;
<br /> ■ Wells MW-2, MW-5 and MW-8 were analyzed for the presence of TPH-G, BTEX, MTBE,
<br /> ' DIPE, TAME, TBA, ETBE;
<br /> - Wells MW-3 and MW-10 were analyzed for the presence of MTBE;
<br /> ■ Well MW-4 was analyzed for TPH-G, BTEX'and MTBE;
<br /> ' ■ Well MW-6 and MW-9 were analyzed for BTEX and MTBE; and
<br /> - We]I MW-7 was analyzed for MTBE, DIPE,TAME, ETBE, and TBA.
<br /> ' The selected analytical constituents were analyzed by US EPA Method 8260B. Copies of the laboratory
<br /> analytical report and chain of custody record are provided in Appendix C.
<br /> ' 4.0 SUMMARY OF RESULTS
<br /> Based on the groundwater-level data for September 30, 2004 (Table 1), the groundwater flow direction in
<br /> ' both the upper and lower aquifers was towards the southeast at gradients of approximately 0.002 feet per
<br /> foot (ft/ft) (Figure 3 and Figure 4). The average depth to water in upper aquifer wells MW-5, MW-6,
<br /> MW-7 and MW-10 increased approximately 0.88 feet since June 2004, and the average depth to water in
<br /> ' the lower aquifer wells MW-1R, MW-2,MW-3, MW-4, MW-8 and MW-9 increased 0.82 feet during the
<br /> same time period. The groundwater flow directions and gradients noted during this sampling event are
<br /> consistent withhistoricalds. �
<br /> ' ��S bf�'GL.PeJ�-4`Wll RC1
<br /> ;�H
<br /> I. ' f aboratory results of groundwater samples collected on September 30, 2004 indicate that
<br /> -G as present at a concentration of 660 micrograms per Iiter (µg/L) in upper aquifer monitoring
<br /> ' weIl MW-5. TPH-G was also reported in lower aquifer wells MW-1R, MW-2 and MW-4 at
<br /> concentrations of 81 µg/L, 62 pg/L and 130 µg/L, respectively. The reported gasoline concentrations
<br /> were flagged by the laboratory for discrete peak in the gasoline range in wells MW-2 and MW-5, and for
<br /> not matching the gasoline standard in wells MW-1R and MW-4. BTEX compounds were reported below
<br /> ' method detection limit concentrations in the sampled wells, except MW-4, where toluene was reported at
<br /> a concentration of 1.7 kg/L. MTBE was reported in groundwater samples collected from upper aquifer
<br /> wells MW-5 and MW-10 at concentrations of 570 } g/L and 0.80 gg/L, respectively. MTBE was also
<br /> ' reported in lower aquifer wells MW-1R, MW-2, and MW-9 at concentrations of 5.2 gg/L, 40 pg/L and
<br /> 1.5 pg/L, respectively. i
<br /> ' Fuel oxygenates DIPE, ETBE and TAME were not detected in groundwater samples collected from any
<br /> of the monitoring wells sampled this quarter. However, TBA was reported in groundwater samples
<br /> collected from wells MW-2 and MW-5 at concentrations of 550 gg/L and 450 deg/L, respectively. The
<br /> ' next quarterly groundwater sampling is scheduled for December 2004.
<br /> Analytical results of groundwater samples collected from current and past sampling events are presented
<br /> 1 in Tables 1 and 2.
<br /> ' Quarterly GW Monitoring Report-3rd Qtr 2004
<br /> CVVATC
<br /> Quik Stop No. 132
<br /> Quik Stop Markets, Inc.
<br /> ATC Project No. 75.62503.3205
<br /> ' November 23,2004
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