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C <br />Organic Vapor Procedures <br />Soil samples collected at 5 -foot depth intervals during drilling were analyzed in the field for <br />ionizable organic compounds using a flame -ionization detector (FID) or a photo -ionization detector <br />(PID) with a 10 2 eV lamp The test procedure involved measuring approximately 30 grams from an <br />undisturbed soil sample, placing this subsample in a ziplock type bag or in a clean glass jar and <br />sealing the jar with aluminum foil secured under a ring -type threaded lid The container was <br />warmed for approximately 20 minutes (in the sun), then the head -space within the container was <br />tested for total organic vapor, measured in parts per million as benzene (ppm, volume/volume) The <br />instrument was calibrated prior to drilling using a 100 -ppm isobutylene standard (in air) and a <br />sensitivity factor of 55, which relates the photoionization potential of benzene to that of isobutylene <br />at 100 ppm The results of the field-testing are noted on the boring logs PID and FID readings are <br />useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon <br />levels with the confidence of laboratory analyses <br />Laboratory Procedures <br />Selected soil and groundwater samples collected were analyzed for the presence of total petroleum <br />hydrocarbons calculated as gasoline (TPH-g), total petroleum hydrocarbons calculated as diesel <br />(TPH-d), benzene, toluene, ethylbenzene, xylenes (BTEX), and methyl tertiary butyl ether (MtB E) <br />using modified EPA Methods 8015 and 8020, with MtBE confirmation calculated using <br />EPA Method 8260 <br />Soil Cuttings and Purge Water <br />Soil cuttings generated during drilling operations were temporarily stored on site and covered with <br />plastic sheeting pending characterization and disposal Contaminated soil cuttings were removed by <br />a California -certified disposal contractor to an appropriate disposal facility Water generated during <br />steam cleaning and development of the new wells was temporarily stored in DOT -approved 55 - <br />gallon drums pending transport by the disposal contractor to an appropriate disposal or treatment <br />facility <br />0 <br />