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detected ni tlic up,tteam ,uitacc water ,arnple {1)DN) wllected from the drainage ditch located east of the site
<br /> Nunc of the other B lTX cornstrtuents or FPH-C> wcrc detected at of above the laboratory reported detection
<br /> tuna, ur tht, ,ample B i 1-X and I PH-(, were not detected un any of the three tetnaining surtacc water samples
<br /> M I BT %gas cleteLled at of above the lahoratoi� reported dctectron limit ui all of the surface. water ,ample, except
<br /> the Sample .ollectM hone the vrennit� of the pump 110nSL in the island diainage channel (ID( W) NOne Of the
<br /> tcniatntns� ,c,leLted gasohne oxv genatesjadditiN e,, were detected at or above the laboratory reported detection
<br /> limas lin an-, of the ,uilaee watci samples
<br /> M I BL (20 awl) \gas the t)nl\ aznalyte detected at or above the laboratory reported detection limits to the, marina's
<br /> pre-treated di inking vNater Only chlorolorm brornodicliloromethane and dibromochloromethane were detected
<br /> III the. marina , heated drinktni; watcl at of above the laborator% reported detection htnitS (at conc.cntrations of
<br /> 18 6 1 and + 0 µa 1 ic,pccti\ek ) ( Itlorotorm b roniodtehloromethanc and dibromochloromethant. appear to
<br /> he byproduct, of the marina , drinking water treatment system
<br /> On I)ce.einber M 1998 t oridor conducted yuartei ly groundwater and 5ut tare water monitoring at l icrman &
<br /> Ilelcrt , 'Marina located at Venice Island I-eny in ' tAOLIctnn, California 1 aboratory analytteal results indicated
<br />' that the, gasoline oxygenate M ME was detected in samples e.ollected from monitor wells MW-1 rJMW-2 MW-3
<br /> and MW-I at c,onLLritrations of 1 3 µgel 11,000 pg/l 3 500 pg/l and 1 5 gg/l, respectively Tertiary-butanol was
<br /> detected rrn the groundwater samples eolfected Born monitor wells MW-2 and MW-3 at concentrations of 150
<br /> pg/l and 130 til;/I icspectively FAME was detected in the groundwater Samples collected from monitor wells
<br /> MW-2 and MW-3 at concentrations of 37 pg/1 and 8 3 pg/l, respectively None of the other oxygenates/additives
<br />' were detected at or above the laboratory reported detection limits in any of the. groundwatLr samples
<br /> toluene was detcctLd in the groundwater ,ainple collictcd tiom nnonrtor well NIW-2 at a concentration of 1 2
<br /> cun,trtuerit, were detceted in the uroundwatei sample, collected from monitor we11 MW-4 at
<br /> eoncentiattort, Of '-I lir/i 0 1 11g11 2 3 rig/l and 22 1t/l respeett4ely 1311 X cotnstrtuents wc.ie not detected ni
<br /> the. groundwatLt ,ainnpleS collect(-d €tom monitor wells tilW-1 and MW-3 I"PH-(j was dctccted in the
<br /> groundwater ,atnplL, colli LtLd from monitor well MW- I at a conct.ntration of 0 2 mg/I I PH-Cr was not dctccted
<br />' in tht- grouindwater ,arnpleS collected lrom monitor WLHS MW-1 MW-2, or MW-3
<br /> Intrinsic bioremediation testing was discontinued at the site following the, third quarter, 1998, monitoring event
<br />' because of inconclusive results and because the petroleum hydrocai bon contamination at the site is probably of
<br /> secondar, conccin iclative to the pre,cnce of gasoline oxygenates The intrinsic bioremediation testing results
<br /> for the four quarter, beginning with the fourth quarter 1997 groundwater monitoring event and tending with the
<br /> third quarter 1998, groundwater monitoring event indicated that subsurface conditions at the site appeared to be
<br /> conducive to the, aerobic and/or anaerobic breakdown of petroleum hydiocarbons Howevei, the results did not
<br /> conclusively indicate that intrinsic bioremediation was occurring at the site No well-defined diffcicnces in the
<br /> intrinsit, bioremediation parameters were established up-gradient (MW-1), in the plume center (VIW-4), and
<br /> down-gradient (MW-2 and MW-3) at the site Phis may be in part related to the relatively low concentrations of
<br /> petroleum hydiocarbons piesent at MW-4 and the very short residence thine of groundwater in the Soil at the site
<br /> Groundwater elevation measurements collected at the site on December 30, 1998, indicated that the average
<br /> depth to groundwater was approximately 4 6 feet bgs which is approximately one-half foot higher than the
<br /> ave.tage groundwater elevation measured on September 30 1998 GiOUndwater elevation contours tot December
<br /> 30, 1998 indicatt~d that the groundwater giadient at the, site was generally consistent with that measured on
<br /> Septembei 18 1997 December 3 1 1997, March 27 1998 June 26 1998 and September 30 1998
<br /> B fI-X and I P11-0 were not detected at or above the laboratory reported detection limits in any of the surface
<br /> water samples Low concentiations of MTBI (1 4 and 1 0 µg/1) were detected in the upstream surface water
<br /> Isample (DDN) and the downstream surface watei sample (DDS) respectively None of the remaining selected
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