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ameO The boring locations may be adjusted in the field based on MIP results or to accommodate surface obstructions. 3.3.1 Drilling Methodology A CPT rig equipped with a MIP will be used to obtain lithologic data, determine the presence of groundwater, and obtain vertical petroleum hydrocarbon concentration profiling data. The CPT borings will be conducted using a piezocone that is pushed into the soil using a hydraulic system connected by stainless steel rods. The piezocone records friction, tip resistance, and pore pressure which is used to evaluate soil types. The CPTs will be performed in accordance with American Society for Testing and Materials(ASTM) standard D5778-95, revised in 2002. The CPT will provide detailed stratigraphic logging with contaminant screening. The MIP is a module that can fit behind the standard CPT piezocone and is pushed into the ground one foot at a time where it acts as an interface between the contaminant in the subsurface and gas phase detectors at the surface. As it is pushed into the cool ground, the heated probe cools. At each foot interval, the probe is allowed to heat back up in order to optimize its ability to volatilize chemical constituents with which it comes in contact. A clean carrier gas passes behind the membrane, causing diffusion across the membrane, and transporting volatile organic to the surface where they are monitored by gas phase detectors. The detectors can measure hydrocarbons that are present in soil and groundwater. Near real-time measurements of volatile organic compound (VOC)and petroleum hydrocarbons can be achieved and a continuous response profile log is recorded for the borehole. 3.3.3 Grab Groundwater Sampling To supplement the MIP results, one groundwater grab sample will be collected from each soil boring CPT-1 through CPT-4 by setting temporary wells installed at each boring location. The first encountered groundwater samples will be obtained using a new disposable polyethylene bailer with a bottom emptying device. After the collection of the groundwater sample, water quality parameters will be measured from the sampling interval. Water quality parameters to be measured include pH, electrical conductivity (eC), dissolved oxygen (DO), oxidation reduction potential (ORP), and temperature. Grab groundwater samples will be analyzed for the following constituents as shown in Table 1. • TPHg by United States Environmental Protect Agency(U.S. EPA) Method 8015M; • TPHd by U.S. EPA Method 8015M; and • BTEX, fuel oxygenates compounds (Di-isopropyl ether, Ethyl tert-butyl ether, Tert- amyl methyl ether, Tert-Butanol, Methyl tert-butyl ether), and lead scavengers (1,2-Dibromoethane and 1,2-Dichloroethane) by U.S. EPA Method 8260B. AMEC Geomatrix, Inc. P:\Project\14000s\14443_Callrans\TO 10\11000_PLANS\AS WP—March 2010WS WP.doc 7 u