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ENVIRONMENTAL INVESTIGATION REPORT Unocal Service Station No 5886 2701 West March Lane Stockton California Delta Project No D095-066 Page 3 Following the Inspection of the product lines, soil samples were collected beneath the former dispensers and along approximately every 20 feet of associated piping Additional samples were also collected at ' bends and joints in the piping Soil sample locations were selected by SJCEHD The sample locations for the dispenser and associated piping samples are presented in Figure 3 Soil samples were analyzed tfor total petroleum hydrocarbons(TPH) as gasoline, TPH as diesel, and benzene, toluene, ethylbenzene, and total xylenes (BTEX) In addition, SJCEHD requested that the soil sample collected beneath the ' fresh oily substance be analyzed for waste-oil This sample was also analyzed for cadmium, chromium, lead, nickel, zinc, halogenated volatile organics, and semi-volatile organics All samples were submitted ' to Sequoia Analytical laboratory of Sacramento (Sequoia), California (ELAP #1624) for chemical analyses The former canopy footings were removed by a subcontractor of Valenzuela Engineering, after the removal of the dispenser piping and associated soil sampling This work was performed as part of the Mpermitted construction work for the station upgrade The canopy footing removal was performed by the subcontractor concurrently with the demolition, loading, and debris removal activities at the site The ' canopy footings were removed by initially digging a trench with the on-site excavator adjacent to each footing The footings were approximately eight feet in depth and four feet in diameter Once the Initial ' trench was dug, a second trench was dug perpendicular and adjacent to the footings This exposed the concrete footing on two sides Once exposed, the footing was pushed into the trench and dragged out ' using the excavator ' Visually Impacted soil was observed after the footings were removed immediately adjacent to both the northern and southern canopy footings Material was removed from the canopy footing areas and the ' trenches were squared using the on-site demolition excavator to facilitate sampling After the construction debris at the site had been loaded and removed from the site, the excavator operator collected soil samples ' from the base and sidewalls of the northern and southern canopy footings using the excavator bucket The methods used to perform the described field work are In Appendix B, Field Methods and Procedures i ' RPT 160 SJS