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1 <br />'. Quarterly sampling of Total Petroleum Hydrocarbons quantified as Diesel {TPH-D} was discontinued <br /> during the third quarter 2002. Condor documented approval by the SJCEHD regarding discontinuation of <br /> TPH-D as a quarterly monitored analyte in a letter to Mr. Knoll dated September 26, 2002. SJCEHD <br /> approval was based on historical data indicating that the presence of TPH-D in site groundwater has been <br /> sporadic, very low in concentration, and likely the result of weathered gasoline rather than from the <br /> possible presence of diesel in the source area. <br /> Condor conducted the third quarter 2002 groundwater monitoring event at the site on September 30, <br /> 2002. Groundwater samples were collected and submitted for laboratory analysis from monitor wells, <br /> MW-1, MW-3, MW-4, MW-S, MW-6, MW-7, and MW-8. No sheen or separate phase petroleum was <br /> noted in the wells, but a strong petroleum odor was noted in MW-1, MW-3, and MW-8 and a very slight <br /> 1 "earthy" odor was noted in MW-7. The groundwater samples collected from the monitor wells were <br /> analyzed for BTEX, THP-G, and selected gasoline oxygenates/additives including MTBE by a California <br /> certified laboratory. Laboratory analytical results for the September 30, 2002, monitoring event were <br /> generally consistent with historical laboratory analytical results. <br /> The average groundwater elevation was approximately 1.71 feet lower on September 30, 2002 than the <br /> previous sampling event conducted on June 26, 2002. The groundwater elevation contours estimated with <br /> the depth to water measurements indicate the groundwater gradient was generally towards the west on <br /> September 30, 2002. The groundwater gradient estimated with MW-3, MW-4, and MW-7 was 0.0013 <br /> ft./ft. towards the northwest, and was generally consistent with historical groundwater gradients <br />' estimated for the site. <br /> 1 <br /> • <br /> 1 <br />