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va sample points from this boring are depicted on Figure 4. Soil samples were collected in accordance with WaterWork's Soil Sampling protocol (Appendix IV). These samples were analyzed for one or more of the following: BTEX (EPA 8020), TPHG and TPHD (DOHS LUFT), Chlorinated hydrocarbons (EPA 8010), Semi Volatile organics and PCa's (EPA 8270), oil and. grease (EPA 503), and Metals Cd, Cr, Pb and Zn (AA). The E` laboratory results of these samples are summarized on Tables 2 and 3. The laboratory data sheets, laboratory quality 1:4 control data and chain-of-custody fo.:m for these samples are contained in Appendix VIZI. The drill cuttings were stored on an asphalt surface adjacent to the former tank pit. The boring was abandoned by " filling to the surface with neat cement. 4.0 QUALITY ASSURANCE/QUALITY CONTROL PROGRAM waterWork's Quality Assurance end Quality Control (QA/QC) Plan (Appendix IV) outlines the field and laboratory procedures followed to obtain representative data. The previously referenced monitoring and sampling protocols (Appendix IV outline additional QA/QC procedures. The field investigation was conducted under the direct supervision of Russell ,7uncal, California Registered Geologist No. 3864, and Nora H. Kataoka, California Registered Civil Engineer No. 38322. 5.0 SUBSURFACE CONDITIONS 5.1 Field Inspection_ The sails encountered during excavation and drilling operations consisted predominantly of lean clays and elastic silts, with thin intervals of poorly graded sands to 50.0 feet, the maximum depth explored. A cross sectional view (A-A' on Figure 3) of the soil stratigraphy near the waste oil tank is depicted on Figure 5. Hydrocarbon odors were noted during the diesel tank re-excavation. Slight diesel odors were noted in the excavation to a depth of 15 feet but were absent in the excavation floor (.16.0 feet) and the north and south walls. Slight product odor persisted in the soils on the west wall of the excavation. Near the waste oil tank hydrocarbon odors were reported in well boring MWl in the interval between 14 and 20 feet below grade. Field _ inspection did not record the presence of hydrocarbon vapors or visual staining of soils typically associated with _hydrocarbon.._.contamination__in angle -soil --boring-- ASBI.:__ The - only samples to register a reading on the PID were in the 8 to 20 foot interval from boring MW1. PID readings ranged from 13 to 182 porn with the highest level recorded at a depth of 12 feet. ,.. 5