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USA 65 - QTR RPT 12/94 USA Gasoline Corporation has installed 1.0 monitor wells in the course of the investigation of this site . Six of these wells are located within the USA property boundaries and four wells are located to the south in a downgradient direction (see Figure 3) After the existing wells were in place (excluding MW8) , a Problem Assessment Report was prepared December 5, 1989 This report was included in Appendix A of the Quarterly Monitoring Report of September 24 , 1991 It presented Soil Boring analysis, Ground water analysis, Ground water flow direction, Aquifer test data with an estimate of transmissivity and hydraulic conductivity, and an evaluation of the zero line of contamination On February 8 , 1993 , MW8 was installed eight feet southeast of the tank field This location was in a hydraulic downgradient direction from the tank field (see Figure 3) A Limited Drilling Report was prepared on February 25, 1993 to document the methods and procedures used to construct the well That report was included as Appendix C of the May 4 , 1993 Quarterly Monitoring Report The well was sampled for the first time on March 31, 1993 GEOLOGY The deposits under the site are Recent to Pleistocene age alluvium and consist of lenticular silt , sand, gravel and clay representing a heterogeneous fluvial environment The Problem Assessment Report for this site (Appendix A of the Quarterly Monitoring Report for September 24 , 1991) details the local and regional geology and hydrogeology The soil samples and drill cuttings from MW8 indicated similar lithologies to those presented in the Problem Assessment Report HYDROLOGY Ground water elevations at the site ranged between 5 and 6 feet below sea level from January 20 , 3989 to April 18, 1989 From April 18 , 1989 through September 13 , 1991, ground water elevations decreased an average of eight feet, to approximately 13 feet to 14 feet below sea level This decrease may be attributed to both sampling time (summer vs winter) as well as an effect of the continuing drought period Ground water elevations increased approximately 234 to 3% feet since the last depth-to-water measurements on September 29, 1994 This recharge is effecting the current ground water elevation gradient across the site and has increased from the fairly flat slope of 0 002 (0 002 feet per linear foot) from MW1 toward MW6 during the Septemeber 29, 1994 gauging to a greater slope of 0 006 from MW5 to MW7 and 0 004 from MW3 to MW2 The flow direction is to the south, southwest from MW5 to MW7 and to the 2