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' OES-Idlewild Market September 26,IM Page-2- ' sidewalls of Pit 1 following over-excavation Field observations made during the over-excavation indicated a light brown silt-pan with grey mottling was present from a depth of 6 feet to i 1 feet ' below the ground surface in the sidewalls of Pit I The total depth of the over-excavation was approximately 17 feet below the ground surface 3.0 SOIL INVESTIGATION Two angle soil borings, SB i and SB2 as shown in Figure 3, Appendix A, were drilled at the site to assess the lateral and vertical extent of petroleum contamination to the north of Pit 1 Prior to drilling, the Underground Service Alert (USA) was notified to locate known underground utilities at I the site The soil borings were drilled by B and F Drilling of Rancho Cordova, California (C57 License #519428) The boreholes were drilled using 6-inch O D , hollow-stem, continuous-flight augers and the augers were steam-cleaned prior to drilling each boring SB 1 was oriented N37E and drilled at an angle of approximately 45 degrees from the horizontal SOB2 was oriented N64W and drilled at an angle of approximately 60 degrees from the horizontal SBI and SB2 were Terminated at , a total vertical depth of approximately 21 feet below the ground surface 4.0 SAMPLE COLLECTION& FIELD OBSERVATIONS Soil samples were collected from each borehole at vertical intervals of approximately five feet w using a California-modified, split-spoon sampler fitted with three clean brass tubes Prior to collection of each sample, the split spoon was washed in a solution of non-phosphate detergent and laboratory grade, hydrocarbon-free water and triple rinsed in hydrocarbon-free water Due to the angle at which the borings were drilled, the split-spoon was hydraulically pushed, rather than pounded, ahead of the augers during sample collection The upper-most tube was discarded The middle Sample tube was retained for geologic logging and field screening The bottom-most tube was immediately sealed with I aluminum foil, capped, wrapped with duct tape, labeled, and stored in a cooler chilled with Blue Ice to await shipment to the laboratory Geologic logs were prepared by a Condor geologist trained and experienced in the use of the Unified Soil Classification System and who was working under the supervision of a registered engineer All soil samples were screened in the field using a portable Organic Vapor Analyzer - F lame Ionization Detector (OVA-FID) The soil from the ground surface to a depth of approximately six feet below the ground surface was medium- to dark brown, sandy silt Grey brown, indurated silt (silt-pan) with minor amounts of sandy clay was present from a depth of approximate 6 feet to a depth n I L� CONDOR