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Phase II Environmental site Assessment Workplan 324 East 11th Street,Tracy,CA June 20,2013 Page 3 of 5 adjacent the existing building. To control cost and physically inspect for the presence of USTs, these four soil borings may be completed using hand augering techniques. From each boring Pangea will screen soil, analyze one shallow soil sample, and analyze one groundwater sample as described below. Based on data from the Tracy High School, Pangea anticipates first encountering groundwater approximately 10 to 13 ft below grade surface(bgs). Prior to initiating field activities, Pangea will conduct the following tasks: • Submit an investigation workplan and obtain drilling permits from San Joaquin Environmental Health (SJEH); • Pre-mark the boring locations with white paint, notify Underground Service Alert(USA) of the drilling and sampling activities at least 72 hours before work begins; • Prepare a site-specific health and safety plan to educate personnel and minimize their exposure to potential hazards related to site activities;and • Coordinate with drilling and laboratory subcontractors and other involved parties. Pangea will conduct site investigation using hand auger and/or a direct-push sampling rig. If used, the direct-push sampling rig will be equipped with a hydraulic hammer and steel drive rods to advance the borings to total depth. With hydraulic-push drilling, continuous soil collection is conducted using acetate liners and samples are typically collected on four foot intervals. Soil samples will be obtained by cutting 6-inch subsections, trimming the excess soil from the ends, and capping the ends with Teflon tape and plastic caps. The soil samples will be classified according to the Unified Soil Classification System (USCS) and screened for field indications of petroleum hydrocarbons using visual and olfactory observations. At each boring location, soil samples will be collected every four feet and a grab groundwater sample will be collected for laboratory analysis. A single grab groundwater sample will be collected from each sampling point using temporary PVC casing installed into first-encountered groundwater. Based on borings from the adjacent Tracy High School, groundwater is anticipated to be present between approximately 10 to 13 ft bgs. All site investigation activities will be performed under the supervision of a California Registered Civil Professional Engineer (P.E.). Additional soil and assessment procedures are presented in our Standard Operating Procedures(SOPS) in Appendix C. Groundwater samples and select soil samples will be analyzed for the following: total petroleum hydrocarbons as diesel (TPHd) with silica gel clean up and total petroleum hydrocarbons as gasoline(TPHg)by EPA Method 8015Cm; and benzene,toluene, ethylbenzene,xylenes(BTEX), and for methyl tertiary butyl ether (MTBE) by EPA Method 8021B. Additionally, groundwater