|
1
<br /> SECOND QUARTER,2000
<br /> GROUNDWATER MONITORING REPORT
<br /> 16, USA STATION#110 -STOCKTON
<br /> JULY,2000
<br /> Groundwater elevation measurements indicate groundwater was flowing to the east at a hydraulic
<br />' gradient of approximately 0 001-feet/feet at the tune of this gauging event A review of the
<br /> historical field data suggests that the groundwater generally flows to the east with minor
<br /> fluctuations to the north and south, as shown on Figure 5
<br /> 3.2 Results of Laboratory Analyses
<br /> 1 All petroleum compounds were non-detect (ND) at the method detection limit in MW-1P, MW-2,
<br /> I
<br /> MW-5P, and MW-6P for this sampling event TPH G was reported in monitoring wells MW-1,
<br /> MW-2P and MW-3P at 720 micrograms per liter (µg/1), 440 ,ug/1 and 160 µg/1, respectively
<br /> Benzene was detected only in well MW-21? at 4 2 ,ug/l Toluene was reported m MW-1,MW-2P
<br /> and MW-3P at 19µg11, 5 5 µg11 and 6 0µg/1, respectively Ethylbenzene was reported in MW-1
<br /> and MW-2P at 10µg/1 and 0 73 µg/1, respectively Xylenes were also reported in MW-1 and
<br /> MW-2P at 17µg/1 and 3 2 4g/1, respectively MTBE was ND by EPA Method 8020 in all wells
<br /> sampled this quarter, except MW-1, MW-2P and MW-3P where it was reported at 67µg/1, 15
<br /> µg11 and 60,ug/l, respectively
<br /> 1,2-DCA was reported in five of eight
<br /> p g wells sampled (MW-1P, MW-2P, MW-3P, MW-5P,
<br /> and MW-6P) at concentrations of 23 µg/1, 8.7µg/1, 1 1 µg11, 14 4g11, and 5 6µg11, respectively
<br /> Confirmation analyses for MTBE using EPA Method 8260B reported concentrations in MW-1P,
<br /> MW-2P, MW-3P, MW-4P, MW-1, and MW-2 at 0 74µg11, 7 9µg/1, 55 µg/l, 0.68 µg11, 72 µg/l,
<br /> and 1 Ogg/l, respectively DIPE was reported m MW-1P, MW-3P, MW-5P, and MW-6P at 5 3
<br /> µg11, 10 µg/1, 160µg/1, and 23 µg11 ETBE was reported un MW-5P at 21 µg/1 TBA was
<br /> reported in MW-21? and MW-3P at 10,ugll and 14 µg/l, respectively All other samples were ND
<br />' at the method detection limit for this sampling event
<br /> The groundwater analytical results for this sampling event are summarized in Tables 2 and 3, and
<br /> shown on Figures 6 and 7 Copies of laboratory reports with COC documentation are included
<br /> in Appendix B
<br /> 4.0 SCHEDULE
<br /> The third quarter sampling event for 2000 was conducted on July 11, 2000 and the momtornng
<br />' report will be submitted by September 15, 2000
<br /> 3
<br />
|