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}� 3.0 LABORATORY ANALYSIS
<br /> The groundwater samples were transported to Severn Trent Laboratories, Inc. (STL), a state-certified
<br /> t� 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,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 /> ■ 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 March 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) and 0.01 ft/ft, respectively (Figure 3 and Figure 4). The average depth to water in upper
<br /> aquifer wells MW-5, MW-6, MW-7 and MW-10 decreased approximately 0.51 feet since January 2004,
<br /> and the average depth to water in the lower aquifer wells MW-1R, MW-2, MW-3, MW-4, MW-8 and
<br /> ' MW-9 decreased 0.49 feet during the same time period. The groundwater flow directions and gradients
<br /> noted during this sampling event are consistent with historical trends.
<br /> Analytical results of groundwater samples collected from current and past sampling events are presented
<br /> in Tables 1 and 2. Analytical laboratory results of groundwater samples collected on March 30, 2004
<br /> indicate that TPH-G was present at concentrations of 960 micrograms per liter (µg/L) in groundwater
<br /> monitoring well MW-5 in the upper aquifer. TPH-G was also present in lower aquifer wells MWAR,
<br /> MW-2 and MW-4 at concentrations of 61µg/L, 150 µg/L and 70 µg/L, respectively. BTEX compounds
<br /> were reported below method detection limit concentrations in the sampled wells, except MW-4, where
<br /> toluene was reported at a concentration of 33 gg/L. MTBE was reported in groundwater samples
<br /> collected from upper aquifer wells MW-5 and MW-10 at concentrations of 1,100 µg/L and 3.4 µg/L,
<br /> respectively. MTBE was also reported in lower aquifer wells MW-1R, MW-2, and MW-9 at
<br /> concentrations ranging from 2.9 µg/L in MW-9 to 250 µg/L in MW-2.
<br /> 1 Fuel oxygenates DIPE and ETBE, were not detected in the groundwater samples collected from wells
<br /> sampled this quarter. However, TBA was reported in groundwater samples collected from wells MW-2
<br /> (80 pg/L), and MW-5 (300 µg2)and TAME was detected at concentrations of 2.9 µg/L and 12 4g/L in
<br /> wells MW-2 and MW-5, respectively. The next quarterly groundwater sampling is scheduled for June
<br /> 2004.
<br /> Quarterly GW Monitoring Report-151 Qtr 2004
<br /> MTC
<br /> Quik Stop No. 132
<br /> Quik Stop Markets, Inc.
<br /> JVROJECTSMIK STOP MKTMOS 1321RepoRsVDD4M31 O1f2DURp1 ATC Project No.75.82503.3204
<br /> May 21,2004
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