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Stantec April 12, 2013 Page 2 of 3 HEALTH AND SAFETY Stantec will generate a site-specific Health and Safety Plan for the scope of work as required by the Occupational Health and Safety Administration (OSHA) Standard "Hazardous Waste Operations and Emergency Response" guidelines (29 CFR 1910.120). The document will be reviewed and signed by Stantec personnel and subcontractors performing work at the site. SOIL BORING, SAMPLING AND ANALYSIS Proposed soil borings GP-1 through GP-4 will be advanced at the approximate locations depicted on Figure 2 to collect soil and grab groundwater samples for environmental due diligence. The first five feet of each boring will be advanced via hand auger. Below five feet below ground surface (bgs), the borings will be advanced using a truck-mounted direct-push drill rig equipped with a two-inch diameter Macro Core® sampling device to a total depth of approximately 20 feet bgs. Soil samples will be continuously cored starting at five feet bgs and soil samples will be collected at five foot intervals. Down-hole drilling equipment will be cleaned before advancing each borehole, and sampling equipment will be cleaned between each sampling interval. Each soil sample will be screened for hydrocarbon vapors using a portable photoionization detector (PID). Soils encountered during drilling will be logged using the Unified Soil Classification System (USCS) by a Stantec field geologist, working under the supervision of a California Professional Geologist. Soil samples will be collected using a two-inch by four-foot long core barrel containing a 1.75- inch diameter clear acrylic sample tube. Samples retained for analysis will be sealed with Teflon® sheeting and plastic caps, labeled and placed on ice in an insulated container for delivery to Kiff Analytical (Kill) located in Davis, California under chain-of-custody (COC) documentation. The soil sample with the highest PID reading from each boring will be analyzed for total petroleum hydrocarbons as gasoline (TPHG), benzene, toluene, ethylbenzene, and total xylenes (BTEX), and methyl tertiary butyl ether (MtBE) by Environmental Protection Agency (EPA) Method 8260B. If no PID readings are encountered, then the soil sample from the soil/water table interface will be analyzed. One grab groundwater sample will be collected from each soil boring. Based on the depth to water measurements encountered at other environmental case sites in the vicinity of the proposed 7-Eleven site, groundwater is expected to be encountered in borings GP-1 through GP-4 between approximately five to eight feet bgs. Prior to sampling, a water level meter will be used to confirm that the drive rods do not contain water. The sampler will be driven to approximately five feet below groundwater and retracted three feet to expose a disposable schedule 20 polyvinyl chloride (PVC) screen and allow groundwater to enter the HydroPuncho sampler. The water sample will be collected by lowering a %44"-diameter stainless steel or disposable bailer through the drive rods to groundwater. The groundwater will be bailed from the drive rods, decanted from the bailer into 40-ml VOA vials, and capped. Each VOA vial will be checked to ensure no bubbles are present, labeled, placed on ice, and transported to Kiff under COC documentation. The grab groundwater samples will be analyzed for TPHg, BTEX and MtBE by EPA Method 82608. The drive rods will then be retracted, leaving the disposable drive tip and four-foot length of PVC well screen in the boring. Following collection of the soil and grab groundwater samples, each boring will be tremie grouted from total depth to grade with neat cement. 36084_phase_I I_work_plan_04_11_2013.doc