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Woodward-Clyde Consultants 3.0 RESULTS 3.1 QUARTERLY' GROUNDWA'T'ER MONITORING 3.1.1 Water Levels, Groundwater Flow Direction ° The groundwater level elevations measured by WCC on December 31, 1991 are summarized in Table 3 A groundwater elevation map for these data is presented as Figure 2 On December 31, 1991, the groundwater surface elevation ranged from -56 19 feet in monitoring well MW-3 to -56.14 feet in monitoring wells MW-1 and NfW-2 The direWon of groundwater flow at this time was toward the south. 3.1.2 Analytical Results Groundwater samples from monitoring wells NiW-1 through MW-3 were analyzed for TPH gasoline by EPA method 5030, BTEX by EPA method 8020, total lead by EPA method 7420, and total coliform by Standard Method 9921 The laboratory results are presented in Appendix B These results are summarized in Table 2 TFH and benzene concentration maps are presented on Figures 3 and 4, respectively. The analytical results for ethyl benzene and total lead were below the detection limit of the analysis in all three monitoring wells The December 31, 1991 results indicate that dissolved phase hydrocarbons are present in the groundwater beneath the site As shown in Table 2, the highest concentrations were detected in monitoring well MW-2 (TFH at 4 1 mg/L, benzene at 1900 µg/L, toluene at 8 7 µg/L and total xylenes at 180 µ911) The analytical results for total coliform were 2 MPN/ml for MW-1, 27 MPN/ml for MW-2, of 17 MPN/ml for MW-3 Sampling results from the August 20, 1991 investigation reported total and fecal coliform values for MW-1 of 17 MPN/ml (total) and <2 MPN/ml (fecal), for MW-2 the respective values were 80 MPN/ml (total) and 2 MPN/ml (fecal), and for MW-3 the respective values were 90 MPN/ml (total) and 6 MPN/ml (fecal) 91CO238BIMAJORMART QRPT 02-20-92 3-1