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Soil samples collected during drilling were submitted to a state-certified laboratory and analyzed for TPH-G,TPH-D, and benzene, toluene, ethylbenzene, and total xylenes (BTEX). The results of laboratory analysis of soil samples are listed in Table 1. In addition, select soil samples were analyzed for total organic carbon, bulk density, specific gravity, and grain size distribution. Refer to Appendix B for a description of the analytical methods used and copies of the official Laboratory Reports, Quality Assurance/Quality Control (QA/QC)Reports, and Chain of Custody Records. 4.2 ELEVATION SURVEY, FLUID-LEVEL MONITORING, AND GROUND WATER SAMPLING On May 27, 1993, fluid levels in Monitoring Wells AW-1 through AW-12 were measured. See Figure 3 for a ground water elevation contour map developed from the May 27, 1993, ground water elevation data. On June 10, 1993, well elevations were surveyed relative to a city benchmark. On May 27, 1993, ground water samples were collected from all wells in accordance with standard regulatory protocol. Refer to Appendix A for a description of fluid-level monitoring and ground water sampling procedures. Ground water samples were submitted to a state- certified laboratory and analyzed for TPH-G, TPH-D, and BTEX. The results of ground water sample analysis are listed in Table 2, and are shown on Figure 4. Refer to Appendix B for a description of the analytical methods used, and copies of the official Laboratory Reports, QA/QC Reports, and Chain of Custody Records. 4.3 SOIL AND GROUND WATER DISPOSAL Drilling activities on March 25, 1993, generated approximately 2 cubic yards of soil. Drill cuttings were stored onsite on polyethylene sheeting. On April 26, 1993, this soil was properly disposed of at a Mobil Oil Corporation (Mobil)-approved facility. Approximately 950 gallons of ground water generated during well development and sampling was stored onsite in Department of Transportation (DOT) approved drums, and approximately 6,000 gallons of ground water generated during the aquifer tests was stored onsite in a Baker tank until transported by vacuum truck for proper disposal at a Mobil-approved facility. 5.0 AQUIFER TESTING On April 13, 1993, step drawdown testing of one monitoring well (AW-9) was conducted to evaluate onsite pumping well efficiency and well yield. A 48 hour constant rate pumping test was conducted from AW-9, from April 14 to April 16, 1993, to estimate the aquifer transmissivity, storativity, and lateral ground water flow rates. Monitoring wells AW-1 and AW-10 through AW-12 were used as observation wells during the constant rate pump test. The • 4