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Each of the groundwater samples will be collected using dedicated and disposable polyethylene bailers and laboratory-supplied containers. The sample containers will be labeled, packaged in an iced cooler, and transported with chain-of-custody documentation to a state of California-certified hazardous waste testing laboratory for analysis. The laboratory will analyze the groundwater samples for TPH-as-gasoline and BTEX by EPA Method 8021 B/805M or 8260B, and for MTBE, DIPE, ETBE, TAME, TBA and 1,2-DCA by EPA Method 82606. 3.2.3 Borehole Abandonment and Site Restoration Upon completion of the groundwater sampling at each location, the temporary wells will be removed and the boreholes will be sealed with neat cement grout, using a tremie pipe. The surface will be restored with asphalt or concrete patches. 3.3 Cone Penetration Testing and Deeper Groundwater Sampling and Analysis To identify a permeable groundwater-bearing interval below the groundwater table and to define the vertical extent of impacted groundwater, cone penetration test (CPT) data and a depth-discrete groundwater sample will be collected from one location near the south end of the former UST (Figure 3). The CPT boring will be advanced to a depth of at least 40 feet„bgs, which is approximately 15 feet below the base of the first groundwater-bearing interval, as observed during the drilling of MW'-I-, The CPT boring will be advanced until a second permeable groundwater- bearing interval is encountered At the proposed location, a pair of borings will be advanced with the CPT rig. The first boring will be used to record tip resistance, sleeve friction and pore water pressure at five-centimeter intervals. i These data will be processed and interpreted in the field. Based on the interpreted soil and ' groundwater parameters, the second soil boring will be advanced to the depth of the second groundwater-bearing interval for the collection of.a discrete groundwater sample. A groundwater sample will be collected from the first permeable groundwater-bearing interval below the groundwater table with a Hydropunch®. After deployment of the Hydropunch at the sample depth, it will be checked for leakage, prior to exposing the sampling screen. Since the soil sample collected at 25 feet during the drilling of MW-1 did not contain reportable concentrations of gasoline compounds, the vertical extent of impacted soil is defined, and no additional soil samples will be collected with the CPT rig. 11