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„ October 4, 1994 Page 4 iselected soil samples using a photo-ionization detector (PID),laboratory analysis of soil samples, and development, sampling, and surveying of newly installed wells. The borings for Wells MW-8 and MW-9 were drilled to a depth of 55 feet below ground surface (bgs) The groundwater monitoring wells were then constructed within these borings to 55 feet bgs The locations and elevations of the top of the monitoring wells were surveyed to mean sea level by a licensed surveyor. The locations of the monitoring wells are shown on Figure 2. Field and laboratory procedures for monitoring well installation and orgaruc vapor analysis, boring logs and well construction details, and well elevation data are presented as Attach- ment A. FINDINGS Subsurface Conditions Soils encountered during drilling of the borings for Wells MW-8 and MW-9 consisted primarily of sandy clay and silt deposits to an average depth of 18 feet bgs Sand was encountered from 18 to approximately 24 feet in the boring for Well MW-8, and was encountered to 28 feet bgs toward the east in the boring for Well MW-9 Clay and silt deposits were then encountered below the sands to the • total depth explored of 55 feet bgs In Well MW-9, a silty sand was encountered from 43 to 46 feet bgs Detailed lithologic descriptions are included on the boring logs presented as Attachment A. Groundwater was first encountered at depths of 46 and 48 feet bgs in the borings for Wells MW-8 and MW-9, respectively. Groundwater elevation data for these wells are presented in Table 1 Quarterly groundwater elevation data for Wells MW-1 through MW-7 were recorded by MPDS Services, Inc. (MPDS) on August 12, 1994. The groundwater elevation data and a groundwater elevation contour map based on the August 12, 1994 data are presented in a MPDS report (Attachment B). During this sampling event groundwater flow was to the northeast at a gradient of 0 003 Organic vapor concentrations in collected soil samples were measured in the field using a PID No organic vapor concentrations were detected. Organic vapor concentrations are shown ori the boring logs presented as Attachment A. Soil Analytical Results Selected soil samples collected from Monitoring Wells MW-8 and MW-9 were analyzed for the presence of total petroleum hydrocarbons calculated as gasoline (TPH-g) according to modified EPA Methods 5030 and 8015, and for benzene, toluene, ethylbenzene, and xylenes (BTEX compounds) according to EPA Meth- ods 5030 and 8020 Soil samples analyzed at approximate 10-foot depth intervals 31004002/MW[NSI AL