ARCHIVED REPORTS_PHASE II PRELIMINARY SITE ASSESSMENT- SOIL SAMPLING AND TESTING

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r r rWeston Ranch Towne Center, Stockton, CA D47223.01page 2 August 21,2006 rJune 20, 2006 workplan. Procedures used in this work are summarized below. ' The field exploration consisted of collecting subsurface soil samples for field screening and laboratory analysis. On July 18,2006,soil sampling was conducted according to the scope of work described in the June 20, 2006 Preliminary Assessment Workplan and San Joaquin County Environmental Health Permit SR# 0047165. ' Soil samples were collected in pre-cleaned stainless steel sampling sleeves. The sleeve ends were covered with Teflon® tape and tight fitting plastic caps. The samples were then labeled and transported under chain-of-custody documentation in a cooled ice chest to Twining's analytical rlaboratory for analysis. Soil descriptions were logged on afield boring log consistent with the specifications of the Unified Soil Classification System (USCS). Soil boring logs are included with this report. Soil samples were field screened for evidence of volatile organic chemicals (VOCs) and/or other petroleum contaminants. The field screening consisted of: 1)visual observation for staining or free fluids, 2) unusual odor, and 3) head space analysis using a photo-ionization detector(PID). The procedures for performing head space analysis are described in the SOPs contained in our workplan. Results of the head space analysis using a PID are included on the soil boring logs. ' Soil samples were submitted for laboratory analysis based on the results of the field screening with ' the PID. Sample handling procedures are summarized in our SOPS. SUMMARY OF RESULTS FROM FIELD INVESTIGATION AND CHEMICAL r ANALYSES The findings and results of the four(4) areas investigated during this assessment are summarized in the following subsections. Residence (612 Henry Lone Bouvelard) Suspected UST rThe former residence was located at 612 Henry Long Boulevard. A geophysical survey was conducted in an attempt to locate the suspected UST at the site. No UST like anomalies were ' identified in the area suspected as having a UST; however, the Ground Penetrating Radar (GPR) displayed a typical signature of a backfilled excavation. One soil boring1 was drilled in the location of the UST reported by the land owner and identified by the GPRbetween the residence and rthe barn. Soil boring B-1 was drilled to a depth of 15 feet below site grade (bsg) and sampled at depths of 5 feet, 10 feet and 15 feet bsg. The soil samples were field screened for evidence of volatile organic compounds (VOCs), none of the samples indicated the presence of VOCs from either visual ' observations, unusual odors or from head space analysis using a photo-ionization detector (PID).