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� Y Phase II Environmental Site Assessment Report 324 East 1 I th Street Tracy, CA July 23,2013 potential former tank location. This could represent abandoned piping associated with former removed USTs. Soil boring B-1 was located adjacent to the potential 20-ft long piping anomaly. No obvious fill material, besides fill within the top 1 ft(likely from paving)was observed during the soil boring activities,suggesting that our two borings(B-1 and B-4) located near the potential UST farm location did not intersect the actual location of any former USTs at the site. Pre-Drilling Activities A comprehensive site safety plan was prepared to protect site workers and the plan was kept onsite during all field activities. A drilling permit was obtained from the San Joaquin County Environmental Health Department.A copy of the permit is presented in Appendix A.The proposed drilling locations were marked and Underground Service Alert was notified at least 48 hours before the proposed field activities. Drilling Procedures On July 8,2013, Pangea coordinated the drilling of six soil borings(B-1 through B-6)at the site(Figure 1). Boring B-1 was located near the 20-ft long anomaly identified during the geophysical survey(potential former UST piping). Borings B-2 and B-3 were located on the western side of the property. Boring B-4 was located near the possible location of the former canopy and/or UST.Borings B-5 and B-6 were located in the northern portion of the site in the assumed downgradient direction.The boring locations were selected to provide lateral delination of hydrocarbons detected at boring B-1.Deeper groundwater sampling of boring B-5 was performed to provide some vertical delination in the presumed cross/downgradient direction from boring B-1. Pangea retained Vapor Tech Services(VTS)of Hayward,California,to drill the borings.VTS conducted the associated soil and groundwater sampling using a Geoprobe 7822DT combination auger/direct push rig equipped with dual tube sampling equipment. Dual-tube direct-push drilling methods employ an outer tube to help avoid cross contamination within the inner sampling tube. All borings were hand augered to approximately five feet below grade surface(bgs)to avoid damaging any unmarked subsurface utilities. After hand augering, VTS drilled the borings using dual-tube direct-push drilling methods to collect continuously cored soil samples. Borings B-1 through B-4 and B-6 were advanced to approximately 15 ft bgs,respectively. Boring B-5 was advanced to approximately 25 ft bgs for vertical delination.Select soil and water samples were collected from each boring in accordance with Pangea's Standard Field Procedures for Soil Borings (Appendix B). Soil samples were collected for laboratory analysis in acetate liners,and capped with Teflon tape and plastic end caps. Soil samples were collected at approximately 5 ft intervals.To sample first-encountered groundwater in 2