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26 September 2014 AGE Project No. 13-2675 Page 4 of 6 SOIL SAMPLING Soil samples will be collected from the boring proposed to 40 feet bsg at discrete five- foot intervals using a 1.45-inch soil sampling assembly loaded with one two-foot long acetate liner. Soil encountered in the boring will be visually classified by an AGE geologist or environmental specialist in accordance with the Unified Soil Classification System (USCS). Soil samples will not be analyzed. Additionally, soil sample duplicates will be field-screened for the presence of volatile organic compounds using an organic vapor meter (OVM), equipped with photo- ionization detector (PID). GRAB GROUNDWATER SAMPLING A grab groundwater sample will be collected from the soil boring advanced to approximately 40 feet bsg. For collection of a grab groundwater sample, a Geoprobe (or similar) push-driven water sampling device will be advanced four feet into the water- bearing zone. Grab groundwater samples will be collected using a Geoprobe water sampling assembly fitted with a pre-cleaned, one-inch diameter 0.01-slotted temporary well screen. Each groundwater sample will be extracted by dedicated disposable polyethylene tubing through the hollow center of the push rods into the screen section. Samples will be analyzed for TPH-g and VOCs and will be collected into laboratory- supplied, non-preserved 40-ml Volatile Organic Analysis (VOA) vials. Appropriately sealed and labeled samples will be placed in a chilled container under ice and transported under chain-of-custody procedure to a CDPH-certified laboratory. Each sample container will be labeled with sample designation, time, date and sampler's initials. SOIL VAPOR SAMPLING Soil-vapor samples will be collected at depths of approximately three (3) feet bsg in the borings advanced for collection of soil-vapor samples. Prior to sampling, temporary soil- vapor wells will be installed in each soil boring advanced. For installation of the soil-vapor wells, temporary/disposable vapor-tips and five feet of '/4-inch Teflon tubing will be lowered to the base of the borings; two feet of tubing will remain outside the borehole for vapor sample collection. Once the tubing and vapor-tip are in place, a filter pack of #3 sand will be placed from the bottom of the borehole to two feet bsg. Following placement of the filter pack, dry bentonite crumbles will be placed atop the filter pack to one foot bsg. Thereafter, bentonite will be placed and hydrated from one foot bsg to near surface grade to seal the vapor well from ambient air Advanced GcoEnvironmental,Inc.