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GROUNDWATER MONITORING On February 2, 1996, a Smith Environmental technician measured the water levels in wells MW-1 through MW-5, well RW-1, and piezometer PZ-1 No floating product was noted in any site well Groundwater monitoring data are summarized in Table 1 The depth to water measurements and the elevations of the well casings (Table 1) were used to evaluate the groundwater flow direction and gradient beneath the site Groundwater elevation beneath the site increased an average of 148 feet since August 21, 1995 Groundwater flow direction was generally to the east at a gradient of approximately 0 0033 ft/ft as depicted on Figure 3 On February 2, 1996, groundwater samples were collected from wells MW-1 through MW-5 for laboratory analyses The field methods used are presented in Attachment 1 Field purge logs are included in Attachment 2 Groundwater samples were analyzed by Sequoia Analytical for total purgeable petroleum hydrocarbons (TPHg) using Environmental Protection Agency (EPA) Method 8015 modified, total extractable petroleum hydrocarbons (TPHd) using EPA Method 8015 modified, and benzene, toluene, ethylbenzene, and total xylenes (BTEX) using EPA Method 8020 Copies of the laboratory reports and chain of custody documentation are included in Attachment 3 Results of laboratory analyses indicated dissolved TPHg was detected in the samples from well � MW-1 at 13,000 parts per billion (ppb) No TPHg was detected in any other site monitoring wells BTEX constituents were detected in well MW-1, most notably benzene at 2,500 ppb MW-5 contained xylenes at concentrations of 0 80 ppb TPHd was detected in wells MW-1 and MW-5 at 1,600 ppb and 180 ppb, respectively The laboratory results of TPHd were reported as unidentified hydrocarbons in the C9-C24 range No TPHd was detected in any other site monitoring wells No petroleum hydrocarbons were detected in monitoring wells MW-2, MW-3 or MW-4 Results of laboratory analyses are summarized in Table 2 SUMMARY AND RECOMMENDATIONS The groundwater flow direction and gradient was generally consistent with those evaluated during previous events Dissolved gasoline hydrocarbons were detected in the samples from well MW-1 Dissolved hydrocarbons in the diesel range were detected in wells MW-1 and MW-5 during the reporting period Dissolved TPHg and TPHd concentrations were below laboratory detection limits in monitoring wells MW-2, MW-3 and MW-4 W X9436719436711 QSR96 doc 2 • SMITH