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`✓ WWI levels of approximately 0 parts per million (ppm). Sample tubes were then sealed at each end using Teflon tape and plastic end caps, labeled, and placed on ice. Selected soil samples were kept on ice and delivered under chain-of-custody documentation to State-certified AEN laboratory for chemical analysis. Field notes and PID readings are contained in Appendix B. Selected soil samples were analyzed by AEN for TPHg, BTEX, oxygenate fuel additives, and total lead. The analytical results for soil samples are summarized in Table 1. Laboratory data sheets and chain-of-custody documentation are included in Appendix C. 2.2.3 Groundwater Monitoring Well Construction Soil boring MW1 was subsequently completed as a groundwater monitoring well to assess potential groundwater contamination beneath the site. During the advancement of soil boring MW2, a strong natural gas odor was detected at 9 feet bgs and the auger was removed from the boring. After removing the auger from the boring, the natural gas odor was no longer evident and PID readings were 0 ppm. PG&E was contacted and Mr. Bob Buker of PG&E inspected the area and informed Smith Technology that there were no underground gas lines in the area. With the approval of Ms. Mary Meays, boring MW2 was terminated at 9 feet bgs and proposed wells MW2 and MW3 were not installed during this investigation. Groundwater monitoring well MW1 was constructed with 2-inch PVC casing. The screened interval of each well was positioned from approximately 5 feet above to 15 feet below the encountered water table to allow for seasonal water level fluctuations. The screen slot size is 0.020-inch. Well construction details are depicted on the well logs (Appendix E). 2.2.4 Monitoring Well Development Newly installed groundwater monitoring well MW 1 was developed on November 17, 1997. The v well was purged until the extracted water was relatively sediment free. Development/purge logs are included in Appendix B. Purgewater was stored on site in 55-gallon drums pending disposal. 2.2.5 Fluid Level Measurement After the fluid level had been allowed to stabilize, the groundwater level was obtained from well MW 1. The fluid level was measured on November 17, 1997 utilizing an electronic water probe capable of measuring with an accuracy of 1/100 of a foot. The depth to water in groundwater monitoring well MW 1 was measured at 17.83 feet. 2.2.6 Groundwater Sampling and Analysis On November 17, 1997, a groundwater sample was collected from well MW I. The sample was collected after purging a minimum of three well volumes and stabilization of electric conductivity, pH, and temperature. The field development/purge log is presented in Appendix B. w:\90954\90954.03Veports\psi.doc 4 • s SIIIITH