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facility within the parking lot and vicinity. Borehole B3 was sited on the southwest driveway east of the former offsite laundry facility. Borehole B5 was located near the northeast corner of the subject property to investigate potential contamination down gradient of the dry cleaning facilities. Westex used a Geoprobe System to collect soil samples at discrete depths from each of the boreholes. Unlike the conventional soil boring technique, the Geoprobe System does not generate soil cuttings from the borehole, but rather depends on compression of soil and rearrangement of soil particles to permit entry and advancement of the probing tool string. The Geoprobe System is an innovative process of advancing a closed sampler to depth, opening the sampler, collecting and retrieving a discrete soil sample. In order to advance the Geoprobe sampling tools, Westex used truck-mounted, hydraulically-powered equipment (Simco 2400 SK-1). During the site investigation, the probe rod string and the Probe-Drive Sampler (24" long by 1.125" diameter) attached to the leading end of the probe rods were pushed or driven with a percussion hammer into the subsurface by the hydraulically-powered machine. The Probe-Drive Sampler was equipped in its leading end with a drive (cutting) shoe and a retractable conical piston tip which cut through the subsoils. During coring, a threaded stop-pin in the trailing end of the sampler assembly prevented the retractable conical tip and rod assembly from retracting into the sampler. When the sampling depth was reached (e.g. two (2) feet, five (5) feet, etc.), the stop-pin which was threaded into the drive head of the sampler, was removed using extension rods inserted down through the probe rods. After the stop-pin was removed, the probe rods and sampler assembly were then driven for 2 feet. The piston tip and rod assembly were then retracted and a soil sample was collected in the sampler. The tool string was then pulled out and the 2-foot plastic tube (containing the sample), previously placed inside the sampler, was removed. A 6- to 10- inch section of the plastic tube was cut from the middle area of the 2-foot plastic tube and retained for laboratory analysis. The ends of the plastic tube were covered with Teflon circle sheets and plastic end caps. The sample was labeled, double-bagged in a plastic bag, placed in a cooler with blue ice and entered on a chain of custody form. The other portion of the sample was disaggregated in a sealable plastic bag and screened for VOCs. After the PID screening, the sample was examined by the Project Manager in accordance with the United Soil Classification System (USCS) under the direct supervision of a California Registered Geologist. The soil type and description and the PID measurements are presented in the Soil Boring Logs (Appendix V). As part of the CRC's Quality Assurance/Quality Control (QA/QC) field procedure, a selected control (duplicate) sample was also retained for laboratory CRC Environmental Risk Management, Inc. Project#2100-217-2 American Savings Bank 150 West 10th Street May 1995 6 Tracy, California