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visually inspected for discoloration, monitored for odors, and classified in accordance with the Unified Soil Classification System (USCS).Select intervals were placed in sealable plastic bags and field-screened with a photoionization detector (PID) calibrated to isobutylene. 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 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; • Up to 39 soil samples will be prepared for laboratory analysis. Based on field-screening results, analyze one soil sample per boring (13 soil samples total)for carbon chain total petroleum hydrocarbons (TPH- cc) via EPA Method 8015 and VOCs via EPA Method 8260; • A temporary soil gas probe will be installed in each borehole at 5 feet bgs after soil sampling. To construct the temporary soil gas probes, the borings will be backfilled with dry, granular bentonite to approximately 6 inches below the desired sampling depth. A new section of diameter Nylaflow tubing with a new '/4-inch diameter polypropylene filter at the terminal end will be inserted into the boring at the desired sampling depth. One-inch diameter polyvinyl chloride (PVC) casing will be used as a guide for the tubing to ensure that the desired sampling depth is achieved. Sand will be poured into the boring annulus to form an approximately 1-foot long sand pack around the polypropylene filter, at which time the PVC piping will be withdrawn. Approximately 1-foot of dry, granular bentonite will be placed atop the sand pack and the remainder of the borehole will be backfilled with hydrated bentonite to the ground surface to form a seal. The sampling end of the tubing will be fitted with a valve for sampling. The final screening depth at each borehole will be adjusted based on the encountered lithology. In general, probes will be screened within coarser-grained materials and clayey/saturated intervals will be avoided, if possible; • Soil gas samples will be collected in general accordance with the July 2015 DTSC and Los Angeles RWQCB "Advisory — Active Soil Gas Investigations." Each probe will be allowed to equilibrate for a minimum of two hours after installation prior to sampling. After equilibration, the sample tubing and sampler screen were purged of ambient air and Partner will collect and prepare up to 13 soil gas samples for laboratory analysis using laboratory-provided, batch-certified SUMMA canisters and flow controllers with a 5- to 10-minute sample period. Each soil gas sample (up to 13 soil gas samples total) will be analyzed for VOCs via EPA Method TO-1 5; • After sampling activities, bentonite and sand pack along with the soil gas probe equipment will be removed from the borings and the borings will be backfilled per SJCEHD requirements and capped with concrete in improved areas; • Data will be compared to applicable screening criteria and a report will be prepared summarizing the field activities, methods, and findings; and • Submit the pertinent data to the SJCEHD for review. Page 4 PARTNER