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1 ' and soil sampling intervals are included in Appendix A. Drilling and well installation procedures are described in Appendix B; well construction data are summarized in Figures 4 , 5 , and 6. ' Well elevations were surveyed on April 30 , 1992 with a Nikon NT-2D Theodolite using an arbitrary datum of 100 . 00, from the top of well ' casing at MW-2 . A groundwater gradient was derived using water elevations observed on April 16, 1992 . The groundwater gradient is presented in Figure 3. 3.0 SITE LITHOLOGY AND FIELD OBSERVATIONS ' Subsurface soils encountered in the three well borings consisted of well graded gravel (typically fill material) from surface grade down to between 2. 5 feet and 4 feet. Below the fill material is a ' medium brown clayey silt with sparse roots and gravel which extends down to an approximate depth of 11 feet to 12 . 5 feet below surface grade. This material was medium stiff and damp. At and below the static water table the soil consisted of brown silty sand with ' sparse gravel ( in MW-1 and MW-3 ) and medium brown clayey silt with fine sand and sandy gravel (MW-2 ) . A medium brown clayey silt was observed at 16 to 17 feet below surface grade in MW-1 . Grab samples of the subsurface soil were obtained at approximately 2 feet below surface grade and at four foot intervals thereafter. No petroleum staining was observed nor was any odor detected. No organic vapors were recorded in any of the grab samples using the Foxboro Century 88 OVA. ' 4.0 SOIL SAMPLING AND ANALYSIS ' Subsurface soil samples were taken from each of the wells near the static water level, at an approximate depth of 12 feet below surface grade. These soil samples were collected with a "Modified California" drive sampler inserted with precleaned brass liners ' which were transported to a State Certified Laboratory for analysis. The results of the analysis are presented in Appendix C as MW-1/12 , MW-2/12, and MW-3/12 referring to samples taken from ' MW-1 , MW-2 , and MW-3 respectively. Soil sampling procedures are described in further detail in Appendix B. No petroleum hydrocarbons as diesel or gasoline nor benzene, toluene, ethyl ' benzene, or total xylenes were detected in any of the soil samples. 5.0 GROUNDWATER SAMPLING AND ANALYSIS ' Initial well development and measurement of the groundwater levels were performed by RMC Lonestar Environmental personnel on October 11 , 1991 . Groundwater samples were taken on November 21, 1991 by RMC Lonestar Environmental personnel and on April 16, 1992 by 2