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piping was encountered. Because of this and the overlapping of the two foot liability zones of the water mains,Fisch refused to advance any borings in the vicinity. A site meeting was held on October 22, 1999 with Spectrum Exploration, and Cal Water Service. It ' was decided that drilling could take place on the western side of Stanislaus St. provided suitable efforts to identify the location of the water mains were made. ' On November 18, 1999, Spectrum excavated a 2 x 2 x 7 foot area with an "air knife" and hand augured to a depth of 15 feet bgs to locate and clear the area of subsurface utilities in the vicinity of proposed boring location HP4. Boring HP4 was then advanced to a depth of 36 feet bgs. by the ' direct push method. During both drilling events, soil samples were collected at 5-foot intervals with a 24-inch long core ' sampler. The sampler was lined with clear acetate sleeves, affording soil identification and subjective evaluation for contamination. A flame ionization detector (FID) was used to monitor the presence of volatile organic compounds in the soil. Soil samples from the borings were ' sealed, labeled, and immediately placed in an iced cooler at a temperature of approximately 40 Celsius for transport to a state-certified analytical laboratory. Soil samples were selected based on observations and field screening results. Boring locations are shown on Figure 2. ' Groundwater samples were collected from borings HPI through HP3 on July 29, 1999, and from boring HP4 on November 18, 1999. To collect the groundwater, a core sampler was driven to the t desired depth and the screen was exposed to the bed within the formation. Samples collected from HP 1 through HP3 utilized 0.17 inch diameter PTFE tubing equipped with a stainless steel check valve that was inserted into the rods to the bottom of the sampler. In boring HP4, % inch diameter PVC casing with a 5-foot screened interval was inserted to the bottom of the boring. Groundwater samples were collected through the casing. Samples were immediately placed into appropriate glass containers, labeled, and placed into an ice chest at a temperature of approximately 40 Celsius. 1 Borings HPI through HP3 were backfilled to the ground surface with neat cement grout and capped with asphalt. Boring BP4 was backfilled to approximately 4 feet bgs with neat cement ' grout, followed by clean fill material and asphalt overlay. Both the fill material and asphalt were compacted to industry standards. All down-hole drilling and sampling equipment was decontaminated by washing with a laboratory grade detergent and rinsing with water. Soil and ' rinseate generated during drilling activities was contained in appropriately labeled DOT approved 55 gallon drums. The drums are currently being stored on site in a secured area pending proper disposal. Soil and groundwater samples were submitted under chain of custody protocol to Argon ' Laboratories for analysis. ' 4.0 RESULTS OF INVESTIGATION 4.1 Subsurface Conditions tSoil encountered in borings HPI through 1HP3 can generally be classified as silt from the surface to 21124 feet bgs, well graded sand from 21/24 to 31/34 feet bgs and clayey sand to lean clay from ' datalg oundzelvalleyvwlsummary.doc 4