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STANDARD OPERATING PROCEDURE SOP Number: 2.1 Date: November 9,2009 STANDARD FIELD SCREENING PROCEDURES Revision Number: 1.1 Page: 1 of 2 1. PURPOSE AND SCOPE This Standard Operating Procedure(SOP) provides instructions for standard field screening. Field screening results are used to aid in the selection of soil samples for chemical analysis. This procedure is applicable during all Ash Creek Associates(ACA)soil sampling operations. Standard field screening techniques include the use of a photoionization detector(PID)to assess for volatile organic compounds(VOCs),for the presence of separate-phase petroleum hydrocarbons using a sheen test. These methods will not detect all potential contaminants, so selection of screening techniques shall be based on an understanding of the site history. The PID is not compound or concentration-specific, but it can provide a qualitative indication of the presence of VOCs. PID measurements are affected by other field parameters such as temperature and soil moisture. Other field screening methods, such as screening for dense non-aqueous phase liquid (DNAPL) using dye or UV light,are not considered"standard"and will be detailed in the site-specific sampling and analysis plan(SAP). 2. EQUIPMENT AND MATERIALS The following materials are necessary for this procedure: • PID with calibration gas (record daily calibration/calibration check in field notes); • Plastic resealable bags (for PID measurement); and • Glass jars or stainless steel bowls(for sheen testing). 3. METHODOLOGY Each soil sample will be field screened for VOCs using a PID and for the presence of separate-phase petroleum hydrocarbons using a sheen test. If the presence of DNAPL is suspected,then screening using dye and UV light may also to be completed. For information regarding screening using dye or UV light, refer to the site specific sampling and analysis plan. PID lamps come in multiple sizes,typically 9.8, 10.6,and 11.7 electron volts(eV). The eV rating for the lamp must be greater than the ionization potential (in eV)of a compound in order for the PID to detect the compound. For petroleum hydrocarbons,a lamp of at least 9.8 eV should be used. For typical chlorinated alkenes (dichloroethene,trichloroethene,tetrachloroethene, or vinyl chloride.), a lamp of at least 10.6 eV should be used. The compatibility of the lamp size with the site constituents should be verified prior to the field event and will be detailed in the site-specific SAP. PID Calibration Procedure: The PID used on-site should be calibrated daily or more frequently if needed. Calibration of the PID should be documented in field notes. Calibrations procedures should be conducted according to the manufacturer's instructions. . PID Screening Procedure: • Place a representative portion (approximately one ounce)of freshly exposed, uncompacted soil into a clean resealable plastic bag. • Seal the bag and break up the soil to expose vapors from the soil matrix. • Allow the bag to sit to reach ambient temperature. Note:Ambient temperature and weather conditions/humidity should be recorded in field notes. Changes in ambient temperature and weather during the field work should also be recorded, as temperature and humidity can affect PID readings. • Carefully insert the intake port of the PID into the plastic bag. • Record the PID measurement in the field notes or boring logs. Sheen Test Procedure: • Following the PID screen, place approximately one ounce of freshly exposed, uncompacted soil into a clean glass jar or stainless steel bowl.