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submitted to the DTSC within four weeks of the groundwater monitoring event (see Appendix D for the prosed project schedule). The reports will include the status of the groundwater characterization and be prepared in accordance with DTSC guidelines. 5.7 Proposed Petroleum Hydrocarbon Release Assessment Six proposed soil borings will be advanced to assess soil and groundwater at the inferred locations of the 1991 petroleum hydrocarbon release as shown on Figure 9. Due to the narrative and map in the 1991 EHD Emergency Response Report and the resulting uncertainty of the location of the hydrocarbon release, the six borings will target pertinent Site features from the historic aerial photographs. Using the former features visible in the 1975 photograph in the Phase I report, two borings will be located near the white building near the center of the Site (referred to herein as the barn), two borings located north of the white building in the area with equipment, one boring near the possible residence with a septic tank along the eastern boundary, and one boring near the possible residence with a septic tank in the southeast corner of the property. The soil borings will be continuously cored using a Geoprobe direct push rig in order to review soil cores within acetate sleeves for petroleum hydrocarbon odor and/or discoloration and for the presence of imported or disturbed excavation backfill material. Boring logs will be generated to record lithology, presence of odors, indications of disturbed or excavation backfill material, field PID readings, driller observations, and sample collection information. Two soil samples from each location will be collected for laboratory analysis as follows: 1.25-inch outside diameter direct push rods will advance a 2.25-inch outside diameter Geoprobe MacroCore sample containing four-foot long 1.7-inch outside diameter acetate sleeves. Based on observations of soil characteristics as within the acetate sleeves (i.e., soil discoloration), the acetate sleeves will be cut with a small handsaw and soil samples will be collected for VOC analysis within five 5-gram plastic cartridges (25 grams of soil total) using EnCore sample T-handles in accordance with EPA Method 5035. Following collection of the Encore samples, a six-inch long portion of the acetate sleeve will be cut with the handsaw, capped, labeled, and stored for analysis to TPH , PCBs, PAHs, and LUFT metals. After soil samples have been collected for analysis, the lengths of the acetate sleeves will be split open in order to observe the soil cores. The soil will be subjectively assessed for petroleum odor and/or discoloration while soil from approximately every two linear feet will be screened with a PID. Four-ounce glass jars equipped with Teflon-lined lads will be available in the event additional soil needs to be collected for analysis of VOCs once the acetate sleeves are split. Grab groundwater samples will be collected within first encountered groundwater anticipated to be at 10 to 12 feet bgs. The groundwater samples will be collected as follows: 1.25-inch outside diameter direct push drive rods will advance a 1.625-inch outside diameter sheath containing a 0.65-inch outside diameter wire- wrapped stainless steel groundwater sample tool. At the point where the groundwater sample tool is advanced approximately two feet below the water table, the sheath will be retracted exposing the four-foot long groundwater sampling tool. The presence and depth of groundwater will be confirmed with an electric powered water level meter and groundwater borings will be purged using a Geotech Environmental Company Geopump peristaltic pump. The groundwater samples will be collected with a small diameter stainless steel bailer and retained 40 milliliter (ml) volatile organic analysis (VOA) vials and maintained and Sampling and Analysis Plan Tracy Corners Shopping Center 3225 North Tracy Boulevard Tracy,California 95376 Partner Project Number SM14-129814 Docket Number HAS-VCA 14/15-108 August 15,2016 Page 20