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a i Privrlged Attorney Work Product KZXMEM 4.2 SOIL BORINGS On November 6, 2012, Bureau Veritas contracted with a California-licensed (C-57) drilling company, Enprobe Drilling Services (Enprobe) located in Oroville, California,to complete the drilling activities associated with this LSI. Enprobe advanced a total of three borings (BV1 through BV3) using truck- mounted direct-push (Geoprobe®) equipment. The three borings were advanced within the proposed utility trench areas to maximum depths of five feet bgs to collect soil samples at the locations identified in Figure 2. During drilling activities, soil cores were collected from the borings. Soil cores were obtained using a 4-foot-long by 2-inch-diameter core barrel sampler. The core barrel contained a plastic liner that retained a relatively undisturbed soil core from which soil samples were collected. 4.3 SOIL SAMPLING Two discrete samples were obtained from each of the three borings at depths from 2.0 to 2.5 feet bgs and from 4.5 to 5.0 feet bgs. These are the expected soil depths to which construction workers may be exposed during the proposed trenching activities. Soil samples were field screened for indications of possible contamination and for the presence of volatile and ionizable compounds using a photoionization detector(PID). The PID records total ionizable compounds in parts per million (ppm) meter units, but is not designed to identify or quantify specific compounds. Selected soil samples were cut from the acetate liners and sealed with Teflon tape and plastic end caps, labeled with identifying information, and stored in a pre-chilled ice-chest awaiting transportation to the laboratory. Selected soil samples were subsequently recorded onto a chain-of-custody document. 4.4 EQUIPMENT DECONTAMINATION New plastic liners were placed in the core barrel prior to each sampling interval. Down-hole equipment was washed in a solution of non-phosphate detergent and double rinsed with tap water after each use. 5.0 CHEMICAL ANALYSES A total of six discrete soil samples were transferred under formal chain of custody protocol to Test America Laboratories, Inc. a State of California certified laboratory, located in Pleasanton, California. Chain-of-custody records were completed and accompanied the sample shipments to the laboratory. The soil samples from the 2.0 to 2.5 feet bgs depths were individually analyzed for the following constituents as noted using United States Environmental Protection Agency (USEPA)-approved methods: Diesel and Motor Oil Range Organics (DRO and MRO) by 8015B with silica gel cleanup. • Polychlorinated Biphenyls (PCBs) by 8082. • Volatile Organic Compounds(VOCs)and Gasoline Range Organics(GRO) by 8260B. The soil samples were analyzed on a standard five business-day turn-around-time. The samples obtained from the 4.5 to 5.0 feet bgs were placed on hold and were not analyzed pending analytical results of the samples from the shallower 2.0 to 2.5 feet bgs depths. 3