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unknown 5" thick, mortar tight, igneous pave stones under the 5" of A/C overlayments. The drill rig was able to drill through the asphalt just fine, but was unable to dislodge the pavers. Penhall Company dispatched a core driller and cored through the asphalt and the pavers in order to gain access for hand pot holing. Pot holing revealed an unmarked utility pipe which necessitated relocating the location 2' over and recoring. Relocating the location now required installing a full lane closure with more signs and an illuminated arrow board, instead of just working in a closed parking lane. These were unfortunate delays and the only work finished on the 6`h was the push bore to determine the lithology of the soil. Soil and water samples were taken the next day on the Th at intervals indicated in the recap of the analytical results. The procedure requires two separate borings,one to determine site lithology and an adjacent boring to collect water and soil samples. The lithology was determined with an instrumented cone penetration head that returns to the test vehicle a continuous flow of data via a signal cable. The data returned to the test vehicle is tip bearing pressure,sleeve side friction,and pour water pressure. This data is graphed with respect to the depth and from that the soil characteristics can be determined for each depth. The estimated lithology from the computer print out is used to determine depths to collect soil and water samples. The most porous layers were sampled. Findings All soil samples from CPT#7 were non detect for BTEX, TPHg, and Oxygenates. Ground water samples from CPT#7 show trace amounts of BTEX compounds, and trace amounts of Oxygenates. All water samples show BTEX and Oxygenates to be within drinking water quality for health. There was not water available at the 30 and 40 foot depths. 50' depth showed 859ppb TPHg, 82' depth showed 58.7ppb TPHg, and 125' depth was nondetect for TPHg. Conclusions When a straight line extrapolation of concentration of TPHg from EW-1 to CPT#7 is used, it indicates that the location of nondetect is approximately 2' west of CPT#7. Recommendations Foothill Engineering recommends that the westerly limits of the plume be established at the center of the #2 NB lane on California Street. REPORT OF FINDINGS FOR THE FOURTH QUARTER 2004 MONITORING EVENT Procedure On December 16, 2004 Del Tech Geotechnical Support Services extracted water samples from all of the monitoring wells on the above stated property and extraction well EW-1. The work was supervised by Foothill Engineering. 3