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<br /> 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-1 R was analyzed for the presence of TPH-G, MTBE,DIPS, TAME, ETBE, TBA;
<br /> ■ Wells MW-2, MW-5 and MW-8 were analyzed for the presence of TPH-G, BTEX, MTBE,
<br /> DIPS, 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 /> +-• ■ Well 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 /> 4. %%.r same time period. The groundwater flow directions and gradients noted during this sampling event are
<br /> consistent withhistoricaltrends. +
<br /> ,6(Sbft } ` KA� 1't U"
<br /> Anal.- ' a'laboratoty results of groundwater samples collected on September 30, 2004 indicate that
<br /> H-G as resent at a concentration of 660 micrograms per liter /L in upper aquifer monitoring
<br /> P � P (pg/L) � PP 9 g
<br /> well MW-5. TPH-G was also reported in lower aquifer wells MW-IR, MW-2 and MW-4 at
<br /> concentrations of 81 gg/L, 62 gg/L and 130 gg/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 MWAR 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 gg/L. MTBE was reported in groundwater samples collected from upper aquifer
<br /> wells MW-5 and MW-10 at concentrations of 570 gglL and 0.80 gg/L, respectively. MTBE was also
<br /> reported in lower aquifer wells MW-IR, MW-2, and MW-9 at concentrations of 5.2 pg/L, 40 gg/L, and
<br /> 1.5 pg/L, respectively.
<br /> Fuel oxygenates DIPE, ETBE and TAME were not detected in groundwater samples collected from any
<br /> +r 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 gg/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 /> in Tables I and 2.
<br /> NOATC
<br /> Quarterly GW Monitoring Report--3rd Qtr 2004
<br /> ulk Stop No. 132
<br /> Quik Stop Markets, Inc.
<br /> ATC Project No. 75.62503.3205
<br /> November 23,2004
<br /> LN Page 2 of 3
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