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clearance for the boring locations from any possible underground utility lines or any detectable subsurface interferences and to determine whether any USTs exist on the subject property. The survey did not detect any evidence of potential USTs onsite. The Norcal report is provided in Appendix IV. 4.2 Soil Boring and Soil Sampling Procedures CRC obtained a Revocable Permit and an Encroachment Permit for drilling the monitoring wells. A drilling permit was obtained from the San Joaquin County Environmental Health Service,7Hazardous Materials Section on September 27, 1995. Copies of the permits are provided in Appendix V. CRC notified the San Joaquin County Environmental Health Services five (5) days before the scheduled '! field work. CRC also notified Underground Services Alert (also known as Digalert) of the proposed drilling four (4) days before the scheduled field work. Prior to the start of the drilling operations, a Tailgate Health and Safety meeting was conducted by the Project Manager to discuss potential health and safety risks ' and the appropriate precautions required to reduce such risks. All field personnel present signed the Attendance List in the Health and Safety Plan (Appendix V) acknowledging that a Health and Safety meeting was held. The soil boring and monitoring well locations are shown on Figure 3, Monitoring Well and Boring Location Map (Appendix I). Western Strata Exploration (Westex) of West Sacramento, California, performed the drilling and monitoring '. well installation under the supervision of a CRC Registered Geologist. Westex used a Geoprobe system to advance the soil borings in the parking lot and in the basement of the building. The monitoring well borings were drilled using a Mobile Drill rig equipped with continuous flight hollow stem augers. The Geoprobe is a hydraulically-powered sampling mechanism adapted on a Simco 2400 drill.rig. The Geoprobe system of coring consisted of a conical piston tip and cutting shoe mounted on a 1-inch outside diameter hollow probe rods. The probe rods were lined with two feet of 0.96 inch diameter by 6-inch long brass liners (tubes) in which soil samples were collected. The probe rod assembly was literally "pushed" into the soil by the hydraulically-powered machine. When the probe tip encountered resistance to the "push" due to rocks or compacted material, penetration was achieved by driving with a percussion hammer until the desired sampling point was reached. A piston stop-pin at the trailing end of the sampler was removed by means of extension rods after the sampler was driven to the desired depth. This enabled the piston tip to retract ' into the sample tube as it was displaced by the soil sample being taken. The tool string was then pulled out and the sample liners extracted. The second sample tube was retained, the ends of the tube covered with Teflon material and plastic ' bags, labeled, double-bagged in plastic bags, placed on ice in a portable cooler and entered into a chain of custody form. A portion of the soil from the bottom CRC Environmental Risk Management,Inc. Project M 2104-250-2 American Savings Bank 222 North El Dorado Street November 3, 1995 Stockton,California