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2.0 SUBSURFACE INVESTIGATION ' 2.1 PRE-FIELD ACTIVITIES ' A minimum of 48-hours prior to initiation of field drilling activities, PSI marked the proposed boring locations with white paint and contacted Underground Service Alert (USA) to locate any potential buried utilities. Additionally, PSI obtained a drilling permit from the SJEHD. ' 2.2 SOIL BORINGS On January 25, 2007, two soil borings (61 and 132) were drilled at the subject property using a direct-push rig for 131 and an hollow-stem auger rig for B2 with both operated by V&W Drilling of Lodi, California. Boring B1 was drilled within the smog testing center adjacent to the two hoists. Originally, two borings were selected for direct-push drilling; however, based on underground lines, equipment within the garage, and the close proximity of the two hoists, one boring was deemed adequate to evaluate the two hoists. Boring 62 was drilled immediately hydraulically downgradient of the former USTs. The locations of the borings are presented in Figure 2. The soil borings logged in general accordance with the Unified Soil Classification System. At the completion of drilling and sampling, each boring was backfilled with tremmied cement grout to the ' surface. Soil and water generated from the drilling and decontamination procedures were contained in DOT-approved 55-gallon drums, which were labeled with the contents, project number, date, and PSI contact information. The drums were left on site pending analytical results for disposal at a suitable facility. ' 2.3 SOIL SAMPLING ' Soil samples were collected from boring B1 at 5-foot intervals beginning at 10 feet bgs for lithologic logging and environmental testing, while soil samples were collected from boring B2 at 5-foot intervals for lithologic logging only. Fieldwork for drilling and soil sampling activities were conducted in general accordance with the field procedures described in Appendix A. Soil characteristics were logged in general accordance with the Unified Soil Classification System. The subsurface materials observed during drilling activities consisted of the following: • Boring B-1: Silty Sand to 2.5 feet below ground surface (bgs) underlain by a Silty Clay from 2.5 to 4.5 feet bgs. At 4.5 feet bgs, a Clayey Silt/Silt was encountered and extended ' to 18 feet bgs. The Clayey Silt/Silt was underlain by a Silty Sand which extended to 20 feet bgs. The Silty Sand was underlain by a silt, which extended to the depth explored of 31 feet. No hydrocarbon odor was noted in the boring and groundwater was not detected. ' • Boring B-2: Silty Clay to 5 feet bgs underlain by a Clayey Silt to the depth explored of 60 feet. Groundwater was measured at 55 feet bgs in the boring. Hydrocarbon odor was not noted during drilling. rThe soil boring logs are presented in Appendix B ' 4