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• Advance three geotechnical borings(B1 through B3)throughout the subject property(with bias towards the future car wash building) to a terminal depth of 20 feet bgs, collect soil samples and blow count readings at 2, 5, 7, 10, 15, and 20 feet bgs; • Advance three geotechnical borings(B4 through B6)throughout the subject property(with bias towards the future parking/driveway areas)to a terminal depth of 5 feet bgs, collect soil samples and blow count readings at 2 and 5 feet bgs; • Advance two percolation borings (P1 and P2) throughout the subject property (with bias towards the future parking/driveway areas) to a terminal depth of 5 feet bgs for infiltration testing only (no soil samples will be collected from these borings); • Advance four environmental borings (B7 through B10) throughout the subject property (with a bias towards the eastern gasoline station and in the vicinity of the proposed future water tank area) to a terminal depth of 15 feet bgs or groundwater, whichever is shallower, collecting soil samples in 5-foot intervals from 5 feet bgs to the terminal depth and a grab groundwater sample at the terminal depth; • Advance five soil gas borings (SG1 through SG5) co-located with borings B2 and B7 through B10 to 5.5 feet bgs to install a temporary soil gas probe at 5 feet bgs; • Geotechnical borings B1 through B3 will be used to collect soil samples in 5-foot intervals from 5 feet bgs to the terminal depth and a groundwater at the terminal depth; • Drilling and sampling equipment will be pre-cleaned priorto arriving on-site. Downhole equipment and materials will be decontaminated in a detergent/tap water and double-rinsed with tap water or with a pressure washer between samples and/or borings to reduce the potential for cross-contamination; • Geotechnical soil samples will be collected from borings B1 through B6 using 5-foot long, 8-inch diameter hollow augers advanced by a CME truck-mounted drill rig. Soil will be penetrated by a cutting bit attached to the lead auger, generating loose soil that is lifted to the surface along the exterior auger flights. Loose soils encountered within the augers will be released by driving the augers vertically up and down. At the desired sampling depth, a California modified split spoon sampler equipped with three pre-cleaned 6-inch long by 2-inch diameter stainless steel liners will be driven into the soil using a hammer system to allow undisturbed soil to enter the sampler liners a maximum distance of 18 inches or until refusal. Blow counts will be recorded for geotechnical purposes. The sampler will be retrieved from the subsurface and the stainless steel liners will be removed and labeled for identification and sent to an in-house geotechnical lab for processing; • Environmental soil samples will be collected from borings B1 through B3 directly from the stainless steel liners using a disposable plastic syringe and retained in one methanol-preserved and two sodium bisulfate-preserved volatile organics analysis (VOA) vials in accordance with United States Environmental Protection Agency(EPA) Method 5035 sampling protocol.A sample will also be collected by transferring soil into a laboratory-supplied, four-ounce, wide-mouth, unpreserved glass jars, which are sealed with a threaded, Teflon-lined lid. The jars will be filled with soil to capacity to minimize headspace and reduce the potential for volatilization. The jars and VOA vials will be labeled for identification and stored in an iced cooler; • Environmental soil samples from borings B7 through B10 will be collected using a 4-foot long by 2.25- inch diameter MacroCore sampler with a 4-foot long acetate liner, which was advanced by the direct- push drill rig using 4-foot long by 1.5-inch diameter drill rods. The sampler will be driven into the subsurface to allow undisturbed soil to enter the open MacroCore barrel and retrieved in 4-foot intervals to recover the soil-filled liners. Soil depths selected for laboratory analysis will be sampled directly from the liners using a disposable plastic syringe and retained in one methanol-preserved and two sodium bisulfate-preserved VOA vials in accordance with EPA Method 5035 sampling protocol. A sample will also be collected by transferring soil into a laboratory-supplied, four-ounce, wide-mouth, Page 3 PARTNER