Laserfiche WebLink
ATTACHMENT B <br /> FIELD AND LABORATORY PROCEDURES <br /> Chevron 9-9840, 4344 Waterloo Road, Stockton, California <br /> • of-custody documentation The well casings were surveyed to the nearest 001 feet in <br /> elevation to a known benchmark <br /> Organic Vapor Procedures <br /> Soil samples collected during drilling were analyzed in the field for ionizable organic <br /> compounds using an organic vapor meter (OVM) or a photo-ionization detector (PID) with a <br /> 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 far, <br /> and sealing the far with aluminum foil secured under a ring-type threaded lid The container <br /> was warmed for approximately 20 minutes (in the sun), then the head-space within the <br /> container was tested for total organic vapor, measured in parts per million as benzene (ppm, <br /> volume/volume) The instrument was calibrated prior to drilling using a 100-ppm <br /> isobutylene standard (in air) and a sensitivity factor of 55, which relates the photo-ionization <br /> potential of benzene to that of isobutylene at 100 ppm The results of the field-testing were <br /> noted on the boring logs PID and OVM readings are useful for indicating relative levels of <br /> contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of <br /> laboratory analyses <br /> Laboratory Procedures <br /> • Selected soil and groundwater samples were analyzed for the presence of total petroleum <br /> hydrocarbons quantified as gasoline (TPHg) and methanol by EPA Method 8015, benzene, <br /> toluene, ethylbenzene, xylenes (BTEX), and fuel oxygenates methyl tertiary butyl ether <br /> (MtBE), di-isopropyl ether (RIPE), tertiary amyl methyl ether (TAME), ethyl tertiary butyl <br /> ether (EtBE), tertiary butyl alcohol (TBA), ethylene dibromide (EDB), 1,2-dichloroethane <br /> (1,2-DCA), and ethanol using EPA Method 8260B <br /> Soil Cuttings and Purge Water <br /> Soil cuttings generated during drilling operations were temporarily stored on plastic or in <br /> DOT-approved 55-gallon drums pending characterization and transport by the disposal <br /> contractor to an appropriate disposal or treatment facility Water generated during steam <br /> 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 <br /> treatment facility <br />