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Shell SITE INVESTIGATION WORK PLAN 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. Figures 2 and 3 are site maps depicting boring locations and select soil sampling analytical data. Table 1 presents the historical soil analytical data. Table 2 presents well construction details. Table 3 presents the historical groundwater monitoring data. Section 2.0 Subsurface Investigation The purpose of this work is to assess the remaining areas where crude oil impact is not delineated. Delineation of the remaining areas identified below was not conducted during the last phase of investigation due to access restrictions caused by the Pacific Gas&Electric(PG&E) overhead high voltage power lines,the sanitary sewer main servicing the Safeway distribution center, Hansen Road, and private property lines. Light Non-Aqueous Phase Liquid (LNAPL) is present in well MW-15. Crude oil impact near MW-15 is delineated to the southeast by data from soil boring B-80 (Figure 3). Crude oil impact near MW-15 is not delineated lateral (northeast and southwest)to the former pipeline alignment. Two soil borings are proposed lateral to the former pipeline alignment at well MW-15(Figure 4). One proposed soil boring is located approximately 50 feet southwest of well MW-15,which has been the typical lateral off-set distance used for delineation at this site. The second proposed soil boring is located approximately 20 feet northeast of well MW-15. The lateral off-set distance for this boring is constrained by the property line. Crude oil impact is not delineated northwest of MW-15 based on soil analytical data from soil boring B-79A (Figure3). A third proposed soil boring will be located approximately 20 feet northwest of soil boring B-79A along the former pipeline alignment. This third boring location is also constrained by the property line. All three soil borings near well MW-15 will be advanced to approximately 40 ft bgs (first encountered groundwater). If impacts are detected at these designated locations, during field monitoring,then step-out soil borings will be advanced to complete delineation unless step-out locations are constrained by the property line and access to the adjacent property. Crude oil impact at soil boring B-109 (Figure 2 and 3) is not delineated lateral to the former pipeline alignment in the northeast direction. One groundwater monitoring well is proposed 90 feet north- northeast of soil boring B-109, located on the property at 24380 Hansen Road (Figure 4). The soil boring for this well will be advanced to 50 ft bgs to match the existing A zone well network unless field indicators dictate an alternative depth. Crude oil impact at soil boring B-109 is delineated to the northwest by boring B-110 and to the southwest by boring B-109A. Delineation southeast of boring B-109 is constrained by Hansen Road and the property line for 24322 Hansen Road,for which property access was denied. 060223(30) 2 CONESTOGA-ROVERS&ASSOCIATES