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... 23 March 2005 AGE-NC Project No. 97-0360 Page 3 of 4 :-- collected and analyzed this quarter. The analytical results of ground water samples are summarized in Table 2. The laboratory report (CTEL Project No. CT214-0410077), quality assurance/quality control (QA/QC) report, and chain of custody form are included in Appendix C. Documents confirming the upload of laboratory electronic deliverable format (EDF) files and depth to water -', measurements to GeoTracker are included in Appendix D. `--' 4.0. SUMMARY AND CONCLUSIONS Based on data collected from the site this quarter, AGE concludes: ; • Ground water flow direction at the site on 13 October 2004 was inferred to be flowing in a trough, generally toward the southOff a gradient of approximately 0.002 ft/ft. The gradient +- this quarter is similar to those measured in previous quarters but the flow direction is inconsistent with previous monitoring events.However,the gradient is so shallow that slight variations in ground water elevation can cause significant changes in the ground water flow - direction. • TPH-g and TPH-d concentrations in well EW-1 remain non-detect this quarter. No other hydrocarbon compounds or fuel oxygenates were detected in well EW-1 this quarter,or have been since ground water monitoring began.(Table 2). (= No analytes were detected at or above laboratory reporting limits in the groundwater samples collected from wells MW-1 through MW-5 this quarter. The lateral extent of petroleum hydrocarbon-impacted ground water has been defined to the north by well MW-4,to the south by well MW-5, and to the west by well MW-3. 5.0. RECOMMENDATIONS Based on the findings of the environmental activities recounted in this report, AGE recommends: • Continuation of quarterly monitoring events as directed by the San Joaquin County Environmental Health Department(SJCEHD)by letter dated 22 June 2004;the first quarter monitoring event for 2005 took place on 10 February 2005. • Preparation of a work plan as required by.the SJCEHD in the letter of response to the AGE- prepared Closure Summary Report, dated 27 January 2004. The work plan is required to delineate vertical and lateral soil contamination southwest,east and south of the former UST. Ground water is required to be delineated east of the former UST. J __. Advanced GcoEnvironmental,Inc.