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Work Plan for Soil Sampling and Laboratory Analyses Page 2 1721 SOUTH CHEROKEE LANE WKA No. 13103.01 March 26, 2021 WKA will coordinate with Enprobe Drilling (a C-57 licensed drilling contractor) to advance four soil borings adjacent to the UST excavation to depths up to 20 feet below ground surface (bgs) using direct push drilling methods. The locations of the proposed soil borings are shown in Figure 2. Soil samples will be collected from the borings to assess whether petroleum hydrocarbon-related fuel products are present in subsurface soil beneath the UST at concentrations exceeding environmental screening levels for commercial land use or indicate an accidental release due to a leaking UST. A continuous soil core will be collected from each soil boring into transparent acetate tubes. A qualified WKA geologist working under the supervision of a Professional Geologist will visually review the soil sample cores and prepare a log of geologic descriptions. The geologic descriptions will be prepared according to the Unified Soil Classification System (USCS). Subsurface soil conditions will be described using the Unified Soil Classification System (USCS). Soil cuttings and a portion of soil samples from each interval will be screened using a photoionization detector (PID) for volatile petroleum hydrocarbon compounds. Following the logging of each soil boring, selected portions will be removed, labeled, and preserved for laboratory analysis. No more than three soil samples will be collected from each soil boring. WKA will label each sample container to indicate a unique sample identification and the time and date collected. WKA will preserve samples in a chilled, thermally insulated container during transport to the analytical laboratory with completed chain-of-custody forms. The locations of the soil borings will be recorded using a high-accuracy Global Positioning System receiver (GPSr). All borings will be abandoned using Portland-type neat cement grout. If groundwater is encountered, grout will be placed using a tremie pipe. Laboratory Analyses No more than eight soil samples will be submitted with completed chain-of-custody forms to California Laboratory Services (a State Water Resources Control Board-certified laboratory) of Rancho Cordova for chemical analyses. The soil samples will be analyzed by the methods identified below: Total petroleum hydrocarbons (TPH) as diesel using EPA Method 8015M; TPH as gasoline using EPA Method 8260B; Benzene, toluene, ethylbenzene, and total xylenes (BTEX) using EPA Method 8260B;