Laserfiche WebLink
i <br /> d <br /> measuring approximately 30 grams from an undisturbed soil sample, placing this <br /> subsarnple either in a plastic zip-lock bag or a clean glass far, and sealing the far with <br /> aluminum foil secured under a ring-type threaded lid The container will be warmed for <br /> approximately 20 minutes (in the sun), then the head-space within will be tested for total <br /> organic vapor, measured in parts per million as benzene (ppm, volume/volume) The <br /> instrument will be calibrated prior to drilling using a 100-ppm isobutylene standard (in <br /> air) and a sensitivity factor of 55 which relates the photo-ionization potential of benzene <br /> to that of isobutylene at 100 ppm The results of the field testing will be noted on the <br /> boring logs PID and FID 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 for Samples Collected During Drilling <br /> Activities <br /> Selected soil and "grab" groundwater samples collected from the soil boring will be <br /> analyzed by a California state-certified laboratory for the presence of total petroleum <br /> hydrocarbons calculated as gasoline, benzene, toluene, ethylbenzene, and xylenes using <br /> modified EPA Methods 8015 and 8020, and lead by EPA Method 6010 <br /> Soil Cuttings and Purge Water Generated During Drilling Activities <br /> Soil cuttings generated during drilling activities will be temporarily stored on and <br /> covered with plastic sheeting pending characterization and disposal Soil cuttings will be <br /> removed by Chevron's disposal contractor to an appropriate disposal facility Water <br /> generated during steam cleaning will be temporarily stored in DOT-approved 55-gallon <br /> drums pending transport by Chevron's disposal contractor to an appropriate disposal or <br /> treatment facility <br /> 9200391A/SITEPULL DOC A - 3 March 24, 1997 <br />