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KL E/NFEL DER Bright people.Right Solutions, 2.2 Qualitative Field Screening An organic vapor detector, such as a Photovac TIP using a photo-ionization detector (PID) or a Foxboro flame-ionization detector (FID), is used to provide a qualitative field screening of each soil sample collected from the probes. The organic vapor detector measures ionizable compounds in the air in parts per million by volume (ppmv). Field calibration is performed using a calibrated span gas such as 100-ppm isobutylene. Ambient air is used to set the instrument to zero. The soil contained in the tip of the sampler or in the end of an acetate sleeve is exposed and screened with the organic vapor detector. The vapor reading is noted as the field screening result. For the protection of the drilling crew, the organic vapor detector is also used to measure the volatile concentrations in the breathing zone prior to and while drilling the borings. Total ionizable hydrocarbon readings in excess of 5 ppmv may necessitate respiratory protection for the affected crew members. 2.3 Geoprobe Groundwater Sampling Groundwater sampling may be conducted from boreholes without the need to install monitoring wells. This method is usually used as an exploration tool for screening groundwater quality and reducing the number of wells needed at a site. A probe is advanced to the desired sampling depth, usually 5 to 10 feet below the top of the groundwater surface, using the Geoprobe core barrel. A five to ten foot temporary screened PVC pipe attached to blank PVC sections are lowered into the boring to provide screening of sediment and a clean conduit to groundwater. Groundwater enters the screened section under hydrostatic pressure and samples are collected using one or more of the following: Small diameter polypropylene tubing attached to a cleaned stainless steel ball valve, peristaltic pump with flexible tubing, or a stainless steel bailer. New PVC screened and blank sections and new or cleaned sampling equipment is used for each sampling location. The groundwater samples collected are decanted directly into laboratory supplied containers appropriate for the requested analyses. The samples are immediately labeled and placed in an iced sample container. The sample container is chilled to at least 4° Celsius. 112884.1/STO10R366R Page ii of iii October 1, 2010 Copyright 2010 Kleinfelder Revision 1,dated November 22,2010