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i RESULTS OF QUARTERLY GROUNDWATER MONITORING GROUNDWATER GRADIENT AND FLOW DIRECTION Figure 4 shows the groundwater elevation gradient and flow direction determined from depth to water measurements at the five on-site monitor wells on June 8 2000 The groundwater elevation has decreased by an a%erage of 198 feet at the five monitor «ells since the previous quarterly monitoring iound on February 23, 2000 The gioundwater elevation gradients forin a trough through the site with flow towards the \,,est The groundwater elevation gradient at the site for June 8 2000 averaged 0 001 feet/linear foot Ovei the site RESULTS OF CERTIFIED ANALYSIS OF GROUNDWATER SAMPLES The results of the certified analyses of groundwater samples collected from the five monitor wells on June 8, 2000 are shown in Table 1 Copies of the laboratory reports are included as Appendix C of this report TPH-G concentrations ranged from a maximum of 22000 ug/1 at MW1 to less than the laboiatoiy detection limits of 50 ug/1 at the remaining four monitor wells Benzene concentrations ranged from a maximum of 2600 ug/i at MW l to less than the laboratory detection limits of 0 5 ug/1 at MW2, MW4, and MW5 MTBE concentrations ranged from a maximum of 130 ug/1 at MW1 to less than the laboratory detection limits of 0 5 ug/l in MW2 Figure 5 shows the distribution of TPH-G BTEX, and MTBE in groundwater as determined from groundwater samples collected on June 8, 2000 The decrease in (lioundwater elevation at the site since the previous quaiteily monitoring round did not produce significant changes iii the concentrations of TPH-G, BTEX, and MTBE observed in the five monitor wells at the site RECOMMENDATIONS Construct a workplan to provide specifications for the following items that have been pre-approved by the UST Cleanup Fund Program 1) Install offsite monitor well west of MW I to define downgradient extent of groundwater contamination plume 3 Sanchez QM 4-6, 2000