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Soil Assessment Report 324 East 11th Street Tracy, California October 12,2017 the planter on the east side of the building (due east from boring B-1) and boring B-13 was drilled near boring B-3. Pangea retained Penecore Drilling (Penecore) of Woodland, California, to drill the borings. Penecore 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. This drilling method allows collection of continuously cored soil samples. All borings were first hand augered to approximately five feet below grade surface (bgs) to avoid damaging any unmarked subsurface utilities. Borings B-11 through B-13 were advanced to approximately 10 ft bgs. Select soil 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 from each boring at approximately 5 ft bgs and 10 ft bgs. Boring logs are included in Appendix C. All samples were shipped under chain of custody to Sunstar Laboratories, Inc., of Lake Forest, California, a California-certified laboratory. The drilling was observed in the field by Pangea staff and supervised by Bob Clark-Riddell, a California Registered Professional Civil Engineer (P.E.). Soil characteristics such as color, texture, and relative water content were noted in the field using the USCS classification system and entered onto a field boring log. Field screening of soil samples for potential hydrocarbons and volatile organic compounds included visual and olfactory observations. Sample Analyses Pangea coordinated soil analyses consistent with the March 15, 2016 agency letter, as required by the agency letter dated February 13,2017. Soil from boring B-11 was analyzed for the following: ■ Volatile organic compounds (VOCs)by EPA Method 8260B; ■ Semi-volatile organic compounds(SVOCs)by EPA Method 8270C; ■ Oil and grease by EPA Method 1664A; ■ Polychlorinated biphenyls(PCBs)by EPA Method 8082; and ■ Cam-17 metals by EPA Method 6010B and by EPA Method 7471A for mercury. Soil from boring B-12 was analyzed for the following: ■ Total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethylbenzene, xylenes (BTEX), and naphthalene by EPA Method 826013; and 3