ARCHIVED REPORTS_SITE INVESTIGATION AND WELL DESTRUCTION PERMIT

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Shell Site Investigation Report agricultural land. However,the Cordes Ranch Specific Plan has been approved by the City of Tracy to allow development of the area for commercial, manufacturing,and distribution use (Figure 2). Refer to CRA's May 13, 2013 Subsurface Investigation Report and Updated Site Conceptual Model for a summary of previous work performed at the site and additional background information. Figure 3 depicts monitoring well locations. Figure 4 presents soil sample analytical data from the recent investigation activities. Table 1 presents well construction details. Table 2 presents the historical soil analytical data. Table 3 presents the historical groundwater monitoring data. Section 2.0 Third Party Geotechnical Investigation Shell was notified on May 2,2014 by the developer for the Cordes Ranch Development project that a geotechnical investigation was scheduled for May. The investigation was limited to a portion of the Cordes Ranch site south of(future) Capital Parks Drive (Figure 2). ENGEO, Inc. (ENGEO)of San Ramon, California conducted the geotechnical investigation. ENGEO advanced 48 soil borings from May 20 through May 27,2014. Boring locations were established in a simple grid pattern over the investigation area. Borings were drilled using a Soil Test Ranger drill rig equipped with 4-inch diameter solid flight augers. Soil samples were collected using a split spoon sample. Soil boring depths varied based on the development plan's grading plan and location of the proposed building, parking lots,and other proposed site features. CRA observed drilling on select days when borings near the former pipelines were being advanced. Figure 4 shows the fourteen ENGEO soil boring locations where CRA collected samples for chemical analysis. California Professional Geologist Bob Siegfried of CRA observed ENGEO drilling activities and collected soil samples from these boring locations.Soil samples were collected at approximate 5-foot intervals in the borings to varied depths,for screening in the field for organic vapors using a flame ionization detector(FID) and laboratory analyses. CRA shipped the soil samples to CalScience Environmental Laboratories, Inc. (CalScience) in Garden Grove, CA for analysis. The samples were analyzed for: • Total Petroleum Hydrocarbons as crude oil (TPHc(C6—C44)) by EPA Method 80158 (M). • Benzene,Toluene, Ethylbenzene, and Xylenes(BTEX) by EPA Method 8260B. TPHc and BTEX were non-detect in all soil samples except for at detection of TPHc at 27 milligrams per kilogram (mg/kg) in sample 1-B07 at 15 feet below grade(fbg). The soil chemical analytical data are summarized in Tables 2. Figure 4 presents soil chemical concentration data for each soil boring. The laboratory analytical report is presented in Appendix B. CRA's independent data validation of the laboratory analytical results is provided as Appendix C. CONESTOGA-ROVERS 0602231351 &ASSOCIATES September20M 2