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' 2.0 METHODS AND PROCEDURES ' 2.1 CPT Drilling Activities Drilling was conducted on October 14, 2004 by Gregg Drilling & Testing Inc (State C57 ' license no 485165) utilizing cone penetration testing (CPT) methods A cone mounted with sensors at the tip was advanced into the soil using direct push rods at the locations shown on Figure 2 The sensors on the cone tested the response of the soil to the force of the penetrating cone and allowed the subsurface stratigraphy to be characterized The cone and rods were advanced to 80 feet bgs using a hydraulic press with a down pressure capacity of approximately 20 tons mounted on a truck-mounted CPT rig A copy of the Gregg Drilling & ' Testing Inc Cone Penetration Test Data is included in Appendix A The CPT drilling techniques allowed for discrete groundwater sample collection from multiple water bearing zones Groundwater samples were manually collected from within the CPT push rods using disposable polyethylene bailers Select soil samples were also collected at each boring location A secondary pilot boring was advanced to a predetermined interval adjacent to the primary boring using the CPT rig Discrete, in situ soil samples were then collected using a piston-type sampling device capable of collecting undisturbed discrete samples 222 Geoprobe® Drilling Activities On December 2, 2004,an ATC geologist supervised the advancement of five soil borings, SB- 1 through SB-5, to approximately 10 feet bgs "Three of the borings (SB-1 through SB-3) were advanced on the subject property and two borings (SB-4 and SB-5) were advanced to the west ' of the site along Holly Drive, for the purposes of evaluating the vertical and horizontal extent of petroleum and oxygenate impacted soil and groundwater A sixth boring was attempted but probe refusal was encountered The boring was abandoned and filled to the surface with neat grout A site plan with soil boring locations is shown on Figure 2 Woodward Drilling (California License C57 710079) advanced the borings using a truck mounted Geoprobe® narrow diameter rig employing direct push technology Soils were continuously collected from ' borings SB-1 through SB-5 in acetate sampling tubes and described according to the Unified Soil Classification System Descriptions of soil types encountered and sample collection intervals are presented on the boring logs contained in Appendix B ' Groundwater samples were collected from borings SB-1 through SB-5 at the depth ' groundwater was first encountered, approximately 5 to 10 feet bgs Upon completion of each boring, slotted 3/-inch diameter PVC well screen was placed within the exposed boring The groundwater was allowed to equilibrate and then samples were manually collected using disposable polyethylene bailers Following soil and groundwater sample collection, the borings were backfilled with neat cement grout to ground surface S 1EnviromcntaM58471Reports\SUM doc 3