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and petroleum product odor were detected in the pipeline sample nearest the dispenser and in the sample beneath the dispenser itself. 2.2 SUMMARY OF PREVIOUS SITE CHARACTERIZATION WORK Soil samples collected from beneath the tanks were submitted to C monie Environmental Laboratories for analysis of total volatile petroleum hydrocarbons (equivalent to total petroleum Chydrocarbons as gasoline, TPHg) and benzene, toluene, ethyl benzene, and total xylenes (BTEX) by EPA Method 8015/8020; ethylene dibromide (EDB) by EPA Method 504, and L organic lead by the Department of Health Services LUFT method. In addition to being analyzed for these constituents, samples from beneath the pipeline and dispenser were analyzed for total extractable hydrocarbons (equivalent to total petroleum hydrocarbons as diesel, TPHd) by methods described in the 1985 edition of."Guidelines for Addressing Fuel Leaks" prepared by the California Regional Water Quality Control Board, San Francisco Region. Analytical results (Table 1) indicated low levels of PHCs detected beneath the four tanks. No benzene was detected in any of the soil samples, and most PHCs (maximum of 120 mglkg TPHg) were detected along the west side of the excavation, beneath Tank #4. PHCs were detected in four of nine samples collected along the pipeline. Trace amounts of toluene, xylene, and ethyl benzene were detected in the sample approximately 120 feet west of the former tanks. Higher levels of PHCs including 0.55 mg/kg benzene and as much as 140 mg/kg TPHg were detected near and beneath the former dispenser island where discolored soil and petroleum odors were detected during the pipeline removal. ,. 3.0 SUMMARY OF ACTIVITIES Drilling and sampling services were performed by Fisch Environmental Exploration Services (Fisch) of Valley Springs California, a C-57 licensed drilling contractor. Borings were advanced using a Geoprobem Model 5400 equipped with a GH-40 Soil Probing Hammer. Prior to drilling operations, Fisch obtained an "Application for Well/Pump Permit" from PHS/EHD to install the soil borings (Appendix A). LDrilling and sampling activities weie conducted on August 4 and 5, in general accordance with procedures described in the Work Plan. The initial boring (B5-1) was drilled to a total depth of 28 feet bgs and was located near the southeastern edge of the former,UST excavation, approximately 10 feet away from the northeastern corner of an existing concrete pad (Figure 2). Per the Work Plan, continuous-core samples were collected from the initial boring using a 4-foot long, 2-inch diameter, Macro-Core Open Tube Sampler equipped with a clear plastic 3 sat 17UNVRPTSWUSTZ v.RFF BOYAJIAN & ROSS, INC. IE;kEnvirenmenial Scientists & Engineers t