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i(YVATC A S S O C I A T E S I N C I Groundwater was encountered during drilling at 715 feet bgs and well MW 1 was completed to a depth of 86 5 feet bgs The well was monitored, purged, and sampled on January 17, 1991 Depth to ' water and groundwater elevation results are summarized in Table 2 The groundwater sample was placed on ice and submitted to Applied Analytical to be analyzed for TPHg and BTEX ' Laboratory analyses of the groundwater samples indicated detectable concentrations of ethylbenzene and TPHg Benzene, toluene, and xylenes were non-detectable Groundwater was resampled for confirmation purposes on January 24, 1991, and only xylenes and TPHg were detected in the sample ' A summary of groundwater laboratory results are presented in Table 3 Field activities are summarized in RESNA Industries, Inc Problem Assessment Report, dated June 6, 1991 ' On July 27, 1994, RESNA personnel supervised the advancement of one soil boring which was completed as a groundwater monitoring well The boring was advanced to 87 feet bgs, 15 feet below ' the water table Soni samples were collected at 64 5 and 70 feet bgs for analysis of petroleum hydrocarbon analytes No petroleum hydrocarbons were present at or above method detection hnuts in either sample Soil analytical results are summarized in Table 1 The location of the well is shown on Figure 3 Subsequent to installation, the wellheads of well MW2 and the facility well were surveyed vertically to the site datum and the survey data were tied to well MW 1 Depth to water readings were collected for gradient direction and magnitude confirmation A sample was collected from MW2 and analyzed for BTEX and TPHg Petroleum hydrocarbon analytes were not present at or above method detection ' limits in the groundwater sample Groundwater analytical results are summarized in Table 3 Field activities are summarized in RESNA's Summary ReportlAdditional Soil and Groundwater Investigation, dated August 19, 1994 4.0 EXISTING CONDITIONS ' 4_1 Soil Conditions Alternating clay, elastic silt and sand are present to a depth of approximately 26 feet bgs From 26 feet ' to approximately 72 feet bgs a very thick elastic silt is present which exhibits gradational color changes and slight moisture differences From approximately 72 feet to 87 feet bgs alternating lenses of silty sand and poorly graded sand (with gravel) are present Soil bonnglwell construction logs are contained in Appendix A ' Based on the analytical results of soil samples collected during the advancement of soil borings, the horizontal extent of soil impacted by petroleum hydrocarbons is limited to the area beneath the fill end portion of the UST The majority of the contamination exists within 36 feet of the fill end portion of ' the UST Soil samples collected from bonngs MWl and MW2 contained no detectable concentrations of petroleum hydrocarbons and only trace amounts of petroleum hydrocarbons were detected in the r w 1943044sportalc1os=doe 3 1