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Mr Kyle Christie August 4, 1995 Page 2 Before sampling, the wells were purged of a minimum of three well casing volumes, or until evacuated, using a submersible pump or polyvinyl chloride (PVC) bailer After purging, each well was sampled using a disposable bailer All groundwater samples were analyzed for benzene, toluene, ethylbenzene, and xylenes (BTEX) and total petroleum hydrocarbons as gasoline (TPH-G) by U S Environmental Protection Agency (EPA) Methods 503018020, and 8015 Modified Field data sheets and chain-of-custody documentation are included in Exhibit A Results and Discussion The general groundwater flow direction beneath the site on May 18, 1995 was to the south under a hydraulic gradient of approximately 0 002 (Figure 1) The hydraulic gradient was somewhat flatter in the area of the soil vapor extraction wells Wells W-2A and W-213 are not used for contouring because they are screened in different zones than the other wells The water-level measured in well W-9 on May 18, 1995 appears to be anomalous and may not represent actual groundwater conditions Therefore it was not used in contouring Since groundwater monitoring began in 1988, the general groundwater flow direction has ranged from southwest to southeast at this site The hydraulic gradient measured this quarter is within the range of previously reported gradients Depth-to-water on May 18, 1995 ranged from 59 34 feet below the top of the well casing (TOC) in well W-8, to 69 35 feet below TOC in well W-9 As discussed above, the water-level measured in well W-9 is anomalous Water-level elevations in all the measured monitoring wells except W-9 increased an average of 175 feet since the last quarterly monitoring event (March 2, 1995) The water-level elevation in W-9 decreased 5 28 feet since March 2, 1995 Monitoring well W-4 contained water for the first time since May 1990 However, it contained only 0 44 feet of water, which was not enough to collect a groundwater sample Summaries of depth-to-water measurements and calculated groundwater elevations are presented in Table 1 Table 2 lists past and present groundwater flow directions and hydraulic gradients for this site BTEX and TPH-G were not detected in any of the sampled wells These results are consistent with previous results First and second quarter 1995 sample results indicate that the December 19, 1994 data for W-5 for benzene (2 2 pg/1) is anomalous Analytical results of groundwater samples are summarized in Table 3 The complete laboratory report for the sampling event is presented in Exhibit A Figure 2 shows TPH-G and BTEX concentrations for this sampling event Status of Site Remediation This section provides a description of the remediation system and discusses the effectiveness of the remediation system operation Use or disclosure of data contained on this sheet is subject to the restriction specified at the beginning of this document 206".EPORTS12ND95QTR RPT