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• and Xylene. No benzene was reported in the groundwater samples. A workplan was prepared for this investigation by JPCA and reviewed by SJCEHD. JPCA also prepared a Site Health and Safety Plan. Contact for location of underground utilities was completed. JPCA requested and obtained a permit from SJCEHD to drill three borings which were converted into wells. The permit is contained in Appendix A. JPCA notified the San Joaquin County Environmental Health Division (SJCEHD) inspector 48 hours prior to initiation of field work. FIELD WORK On the morning of May 30, 1995, John N. Alt and John P. Cummings met with the drilling crew at the parcel located at 18775 Tom Paine Road, Tracy, CA. Mr. Costamagna was also on site. The Site Specific Health and Safety Plan was read and signed by the drilling crew prior to commencement of the drilling operations. Mr. Michael Infurna, SJCEHD inspector, met us and also read and signed the Site Specific Health and Safety Plan. 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, commencing at approximately 5 feet below grade and above the saturated zone. The Boring Logs are contained in Appendix A. Well Construction For Boring MW-1, the first 4 feet was medium brown fine-grained sand both loose and dry, then moist grayish brown silty clay, micaous and moist with organic matter, rootlets, for the next 4 feet. From approximately 9 to 14 feet gray clayey fine sand moist to wet with abundant roots. At approximately 14 feet to 20 feet, the material changed to grey fine to medium wet moist sand with lenses of course brown sand and micaous. A moderate hydrocarbon odor was observed at approximately 10 feet. At approximately 20 feet the boring was terminated. Flowing sands were encountered with sand rising to sixteen feet. Redrilling using a wooden plug was completed to hold back the flowing sands. Fifteen feet of 0.01 inch screened 2-inch=diameter, Schedule 40 PVC, casing with a slip on end cap, 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. Sixteen feet of #2-16 Lonestar Sand was used for the filter pack with a one foot, doubly • 3