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A S S O C I A T E S I N C Advancement of Soil Borings To evaluate the extent of soil and gro co_ ation at the sit up to eight it borings will be advanced to approximatel 15 feet below ground face (bgs). The borings will be placed south and southwest of the si e in the Burlington North Santa Fe Railroad Right of Way. The first three proposed boring locations are shown on Figure 2. Subsequent borings will be advanced in locations determined in the field by ATC and PHS/EHD personnel based on the observations made during the advancement of the three initial borings. The borings will be advanced to using truck mounted Geoprobe® narrow diameter, direct push technology. Drilling will be conducted by a State-licensed (C57) drilling company. A field geologist will be present to log soil samples. Descriptions of soil types encountered and sample collection intervals will be recorded on boring logs. Soil samples will be collected at five foot intervals, field screened with a Photoionization Detection (PID) meter, and up to two soil samples from each of the borings will be submitted for laboratory analysis. Soil sample selection will be based on PID measurements and field observations (i.e. odor and soil discoloration). One groundwater sample will be collected from each boring at the depth groundwater is first encountered, approximately 10 feet bgs. A Geoprobe® Screen Point 15 Groundwater Sampler will be threaded onto the leading end of the Geoprobe when the groundwater is encountered. While the sampler is advanced, O-ring seals and an expendable drive point will provide a watertight system to ensure sample integrity. When the tool has been advanced to the desired depth, extension rods will be sent downhole to brace the bottom of the sample screen as the tool casing is retracted. When the casing is retracted, up to 41-inches of screen with slot sizes of 0.004 inches will be exposed. Teflon tubing with a check valve attached to one end will be inserted down the casing until it is immersed in groundwater. Water will then be pumped through the tubing and to the ground surface by oscillating the tubing up and down. Following soil and groundwater sample collection, the borings will be backfilled with neat cement grout to the ground surface. All drill cuttings, if any, will be stored on site in a 5-gallon container pending laboratory results. Sample Analysis Selected samples will be immediately placedCified d delivered under chain-of-custody documentation to Argon Laboratories, a State-ceoratory, for analysis. Samples will be analyzed for TPHd and total petroleum hydrocarbons as gasoline (TPHg) using EPA Method 8015 Modified; benzene, toluene, ethylbenzene, and xylenes (BTEX) using EPA Method 8020; and oxygenate fuel additives by EPA Method 8260. wA625001reportslwkpH.doc 3