ARCHIVED REPORTS_SEPARATE PHASE HYDROCARBON INVESTIGATION UNOCAL EXTRACTION WELL PILOT STUDY 2011

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• FIELD AND LABORATORY PROCEDURES Cone Penetrometer Testing (CPT) The CPT method consists of advancing a cone-tipped cylindrical probe (1.7 inches-in- diameter) into the ground while simultaneously measuring resistance to the penetration. The CPT method evaluates soil stratigraphy/lithology by comparing the force (cone bearing pressure) required to advance the probe (Qt) to the friction ration (Rf). The Rf equals sleeve friction [Fs] divided by the probe tip load, times the penetration pore pressure [Ud]. Computer generated CPT logs are plotted in the field to provide a graphical log of subsurface soil stratigraphy/lithology. A CPT test data report, including logs of the CPT technique, is submitted with the final report. CPT testing is performed in accordance with American Society of Testing and Materials (ASTM) Method D 5778-95 (Reapproved 2000). The CPT is performed inside a grout collar installed at the ground surface. The grout collar allows the CPT contractor to backfill the boring as the steel rods are retracted from the hole to help prevent cross-contamination of water bearing zones through an open borehole. Each boring is backfilled to surface grade. Grout mix used to backfill the boring is Portland cement, mixed at a ratio of 6 gallons of water per 94 pounds of cement. A concrete or asphalt patch is placed over the borehole where applicable. Ultraviolet Optical Screening Tool • Dakota Technologies Laser-Induced Fluorescence/Ultravioloet Optical Screening Tool (UVOST) system will be used for this investigation to screen soils for petroleum hydrocarbon constituents. The system consists of a tunable laser mounted in the CPT truck that is connected to a down- hole sensor. The down-hole sensor consists of a small sapphire window mounted flush with the side of the cone penetration probe. The laser and associated equipment transmits pulses of light to the sensor through a fiber optic cable. The wavelength of the pulsed excitation light is tunable and can be set to wavelengths of 266 (nm) or to wavelengths between 280 and 300 nm. The laser light passes though the sapphire window and conveyed to a detection system within the CPT rig. The emission data resulting from the pulsed laser is averaged into one reading per one-second interval (Approximately one reading per 2 cm vertical continuous intervals). For this project, UVOST will be operated in multi-wavelength mode (MWL). MWL mode emits fluorescence at four monitoring wavelengths (350, 400, 450, and 500 nm). These four wavelengths cover a color range of light produced by light fuels to heavy contaminants when exposed to excitation light. The relative percentage of fluorescence measured at each monitoring wavelengths is plotted continuously on the UVOST logs as four continuous "color bands." The width of the color bands represents the relative percentage of the contaminant. By comparing the relative percentage ratios of field data to those created by reference standards, interpretations of product type can be made. Relative concentration estimates are based on the intensity of the fluorescence. 30