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Mr Kyle Christie May 15, 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 March 2, 1995 was to the south under a hydraulic gradient of approximately 0 002 (Figure 1) Wells W-2A and W-2B are not used for contouring because they are screened in different zones than the other wells Well W-4 was not used in contouring because it was dry, and well W-6 was not used because EMCON field personnel could not locate the well 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 March 2, 1995 ranged from 6109 in well W-8, to 64 07 in well W-9 Well W-4 was dry Water-level elevations • in all the measured monitoring wells except W-10 increased an average of 198 feet since the last quarterly monitoring event (December 19, 1994) Water level elevation data for monitoring well W-10 was not collected the last two quarters. The water level elevation in W-10 decreased 167 feet since it was last measured on March 22, 1994 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. Neither BTEX or TPH-G were detected in any of the sampled wells These results are consistent with previous values First quarter 1995 sample results indicate that the December 19, 1994 data for W-5 for benzene (2 2 µg11) is anomalous The detection limit for benzene is 0 5 pg/1 and for TPH-G is 50 pg/l. 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 206SREPORTSM ST95QMJtYr