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elliptical closure. Any suspected anomaly was further verified by running a GPR survey. The GPR method provides a continuous, high resolution profile, depicting variations in the electrical properties of shallow subsurface materials. Data are continuously collected and automatically recorded graphically versus time and can depict subsurface anomalies (e.g., buried tanks, pipes, etc.) The results of the UST investigation did not indicate any anomaly which may be attributed to the presence of USTs on the site. NORCAL also investigated the locations of the boreholes for the presence of any subsurface utility lines or obstructions. Both GPR and electromagnetic line locating (EMLL) techniques were used in the survey. The EMLL method detects continuously connected metal pipes, cables, wires and utility lines with tracer wires. Non conductive materials (e.g., concrete pipes) which may not be detected by EMLL was investigated by GPR method. The complete results of the geophysical investigation are presented in NORCAL's Geophysical Report (Appendix IV). 4.3 Tailgate Meeting and Air Monitoring Before the start of the field operations, a tailgate meeting was conducted by the Project Manager with the field personnel. Among the topics discussed were the scope of work, the anticipated risks and health hazards and the precautionary measures to be observed to prevent accident. The group discussed the procedures to be taken in case of emergency. The Project Health and Safety Plan (HSP) was previously furnished to the contractor for review. A reference copy was available at the site at all times during the site investigation. The HSP is provided in Appendix III. As part of the health and safety measures, air monitoring was performed during the progress of the coring and sampling. Prior to the start of the drilling, ambient air measurement was conducted. At regular intervals (15 - 30 minutes) air measurement was performed within the breathing zone of the drill operator and at the boreholes. The results of the air monitoring indicated no adverse readings which could have endangered the field personnel. 4.4 Soil Boring and Sampling Prior to the drilling and sampling, CRC obtained a permit from SJCPHS-EHD to drill three (3) to five (5) boreholes and to collect soil and groundwater samples from each of the boreholes. Copies of the approval letter and Permit No. 005561 are provided in Appendix VII. CRC contracted Western Strata Exploration, Inc., (Westex) of Sacramento, California, to advance and sample five (5) boreholes within the subject property. Boreholes B1, B2, and B4 were located east of the former onsite dry cleaning CRC Environmental Risk Management, Inc. Project H 2100-217-2 American Savings Bank 150 West 10th Street May 1995 5 Tracy,California