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Laboratory results will be compared to San Francisco Bay Regional Water Quality Control Board (RWQCB) Environmental Screening Levels (ESLs). Partner will perform the following tasks for the Phase II Subsurface Investigation: • Prepare a site-specific health and safety plan; • Notify Underground Service Alert of Northern California (USAN) a minimum of two business days prior to field activities to clear public utilities; • Secure the necessary drilling permit from the SJCEHD; • Notify the applicable regulatory agencies a minimum of 24 hours prior to drilling/backfilling activities; • Perform a geophysical survey on all accessible areas of the subject property to identify the location of former on-site tankhold(s) and/or existing UST(s), piping, and/or associated features and to additionally clear boring locations of utilities. Boring placement will be modified as necessary based on the geophysical survey results to avoid damaging underground features. Additionally, to the extent practical based on subsurface lithology, clear boring locations using hand tools; • Advance three borings in the vicinity of the potential on-site UST (based on data from the geophysical survey, site observations, and/or historical records) to a terminal depth of 20 feet bgs, collecting soil samples in 5-foot intervals from 5 feet bgs to the terminal depth; • Drilling and sampling equipment will be pre-cleaned prior to 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. Soil samples 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. A lengthwise section of each acetate liner was removed with a splitting tool to expose the soil. The soil column was 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. Thejars 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 12 soil samples will be prepared for laboratory analysis. Based on field-screening results, one soil sample per boring (four soil samples total) will be analyzed 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 Page 3 PARTNER