Laserfiche WebLink
S ECOR <br /> A California State Licensed Surveyor will survey the newly installed wells. The well <br /> casings will be surveyed to the nearest 0.01 feet in elevation to a known benchmark. <br /> Organic Vapor Procedures <br /> Soil samples collected at 5-foot depth intervals during drilling will be analyzed in the field <br /> for ionizable organic compounds using a photo-ionization detector (PID) with a 10.2 eV <br /> lamp or a flame ionization detector (FID). The test procedure involves measuring <br /> approximately 30 grams from an undisturbed soil sample, placing the subsample into a <br /> sealed container (either a zip-lock bag or a mason jar). The container is warmed for <br /> approximately 20 minutes (in the sun), then the headspace within is tested for total <br /> organic vapor, measured in parts per million as benzene (ppm; volume/volume). The <br /> instrument is calibrated prior to drilling using a 100-ppm isobutylene standard (in air) and <br /> a sensitivity factor of 55 which relates the photo-ionization potential of benzene to that of <br /> isobutylene at 100 ppm. The results of the field testing are noted on the boring logs. <br /> PID and FID readings are used for indicating relative levels of contamination, but are not <br /> used to evaluate hydrocarbon levels with the confidence of laboratory analyses. <br /> Soil Cuttings and Rinsate Water <br /> Soil cuttings generated during drilling operations will be temporarily stored onsite 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 disgpsal facility. Water <br /> generated during steam cleaning, and sampling of the borings Atemporarily stored in <br /> DOT-approved 55-gallon drums pending transport by Chevrons disposal contractor to <br /> �•J an appropriate disposal or treatment facility. <br /> V <br />