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L SECOND QUARTER 2003 GROUNDWATER MONITORING REPORT AND ADDITIONAL ASSESSMENT REPORT JAMAR OIL DISTRIBUTION JUNE 2003 The four wells were completed with 2-inch diameter, flush threaded, Schedule 40 PVC with 0.020- inch perforated and blank casing. A threaded end cap was placed at the bottom of the PVC casing, which was then set through the augers. A#3 sand pack was placed in the annular space between the slotted casing and the boring wall, and extends approximately 2-feet above the top of the screened intervals. The well annulus was sealed from the top of the sand pack with approximately 2-feet of hydrated bentonite chips. The well was sealed from the top of the bentonite to 0.5-feet bgs with a neat cement grout. To protect the integrity of the well, the top of the wellhead assembly was enclosed at the surface in a traffic-rated, flush-mounted well box. All work was completed in accordance with County and State regulations. The boring logs for these four wells are included in Appendix A. Soil samples were collected approximately every 5-feet during drilling for logging purposes. Soil samples were also collected in brass sleeves, using a California split-spoon sampler, from 86 and 91- feet bgs in MW-6B and from 76, 81, 86, and 91-feet bgs in MW-7B. The brass sleeve samples were used to determine a good location to set the well since the deep wells used only 5-feet of screen. The 86-feet bgs brass sleeve sample from both MW-6B and MW-7B were submitted for laboratory analysis. The selected soil samples were analyzed for TPH G and TPH D using EPA Method 8015K and analyzed for BTEX, 1,2-DCA, EDB and the fuel oxygenates MTBE, ETBE, TAME, D1PE and TBA using EPA Method 8260B. The soil sample analytical report is included in Appendix D. This analytical report also includes the groundwater analytical data from the aquifer performance test sampling of EW-1. The soil cuttings were placed on heavy-duty plastic sheeting along the dirt strip in the northeastern portion of the subject site. The soil cuttings were sampled for disposal purposes and covered with plastic. Well Development and Surveying The four newly installed groundwater monitoring wells were developed on May 27, 2003, using both a surge block to develop the sand pack and new bailers to remove the fines not removed by surging. Turbidity was monitored to check the effectiveness of development. The newly developed wells were allowed to equilibrate for 48-hours prior to purging for sampling. The development water was placed into DOT approved 55-gallon drums and labeled accordingly. The purge water drums were stored on the JAMAR site pending laboratory analyses and selection of an appropriate disposition. Disposal of the groundwater will be completed by GHH. The four new monitoring wells and the extraction well were surveyed, using a David White Instruments Laser Level, on June 13,2003. Monitoring well MW-4, which had previously been surveyed to approximate MSL was used as the benchmark. The surveyed elevations are included in Table 1 of this report. 6