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FIELD WORK On the morning of October 20, 1994 , John N. Alt and John P. Cummings met with the drilling crew at the parcel located at 375 W. Hazelton Ave. , Stockton CA. ' SOILS EXPLORATION SERVICES INC. was the driller for the borings and well construction. The Boring Logs were prepared by the Certified ' Engineering Geologist, who directed the drilling and recorded the observations of the geologic materials encountered on site during the drilling. Soil Samples were collected at five foot intervals. These samples were collected for a description of the subsurface soil conditions. Soil samples were collected for chemical analysis when hydrocarbon odor was detected, commencing at approximately 15 feet and above the saturated zone. The Boring Logs are contained in Appendix A. Well Construction For Boring MW-1, the first 2 feet was sand and gravel fill with approximately 4 inches of asphalt, then moist dark brown clay with organic matter for the next 4 feet. From approximately 7 to 12 feet light brown silty clay and clayey sand to fine grained brown sand. At approximately 12 feet to 18 feet, dry brown clayey silt with caliche veins was encountered. The next several feet changed from moist fine to locally coarse sand being moist at approximately 25 feet with a moderate hydrocarbon odor observed. The material changed to grey moist sand, fine to medium grained and moist, well sorted and grading back into a dark grey moist clay at approximately 34 feet. A strong hydrocarbon odor was observed at 30 feet with moderate hydrocarbon odors at 35 and 40 feet. The soil from 34 to 40 feet was dark grey plastic clay with caliche mottling ' and dry. This well was very slow to charge. At approximately 41 feet the boring was terminated. Twenty feet of 0 . 02 inch screened 2-inch-diameter, Schedule 40 PVC ' casing was placed at the bottom of well MW-1. The remainder of the well was constructed using regular 2-inch-diameter, Schedule 40 PVC casing. Twenty two feet of #3 Lonestar Sand was used for the filter pack with a two foot Bentonite seal above the sand. The remaining portion of the well was filled with cement grout and a traffic rated moister resistant manhole placed slightly above grade ' to avoid surface water contamination. A locking cap with lock was placed in the casing to avoid inadvertent surface contamination to groundwater. For Boring MW-2 , the first 4 feet was sand and gravel fill with approximately 4 inches of asphalt, then moist brown silty clay for the next 5 feet. From approximately 9 to 21 feet light brown silty clay and clayey sand to fine grained brown sand with no odors observed. The soil from approximately 22 to 33 feet was moist 5