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SECOND QUARTER 2003 GROUNDWATER MONITORING REPORT AND ADDITIONAL ASSESSMENT REPORT JAIMR OIL DISTRIBUTION JUNE 2003 The well was completed with 4-inch diameter, flush threaded, Schedule 40 PVC with 0.030-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 coarse aquarium 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 interval. The well annulus was sealed from the top of the sand pack with 3-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 log for EW-1 is included in Appendix A of this report. Soil samples were collected for logging purposes approximately every 5-feet during drilling. With the permission of the San Joaquin County representative, no soil samples were taken for laboratory analysis because of the proximity of EW-1 to hydropunch 1HP-1, where soil samples were taken and analyzed in January 2003. Soil cuttings were placed on thick plastic along the dirt strip in the northeastern portion of the subject site. The soil cuttings were sampled for disposal purposes and covered with more plastic. EW-1 was developed on May 20, 2003 by Cascade Drilling Co.(Cascade), the same company that drilled the well 0-57#717510). The well was developed using a surge block to help set the sand pack and was then bailed until the water ran clear. MONITORING WELL INSTALLATION On May 20-23, 2003, four new monitoring wells (MW-6A, MW-6B, MW-7A and MW-7B) were installed offsite. MW-6A and MW-6B are cluster wells located east of the subject site in the sidewalk south of the hamburger stand, as shown on Figure 2. MW-7A and MW-7B are cluster wells located southeast of the subject site in the sidewalk on the south side of Main Street as shown on Figure 2. MW-6A and MW-7A were installed to monitor the upper groundwater zone while MW-6B and MW-7B were installed to monitor the lower groundwater zone and to see if there is communication between the two levels. All four of the monitoring wells were drilled by Cascade using a CME-75 Limited Access, hollow stem auger drilling rig. Monitoring well MW-6A was drilled to 75-feet bgs and was screened from 55-feet to 75-feet bgs. Monitoring wells MW-6B and MW-7B were drilled to 94-feet bgs and were screened from 89-fee to 94-feet bgs. Monitoring well MW-7A was drilled to 74.5 feet bgs and was screened from 74.5- feet to 54.5-feet. 5