WORK PLANS - Laserfiche WebLink

Home Browse Search

J ATTACHMENT B FIELD AND LABORATORY PROCEDURES Chevron 9-8632, 575 Grant Line Road, Tracy, CA f Health and Safety As required by the Occupational Health and Safety Administration (OSHA) Standard "Hazardous Waste Operations and Emergency Response" guidelines (29 CFR 1910. 120), and by California Occupational Health and Safety Administration (Cal-OSHA) "Hazardous Waste Operations and Emergency Response" guidelines (CCR Title 8, Section 5192), SECOR will prepare a Site-Specific Health and Safety Plan prior to the commencement of fieldwork. The Site-Specific Health and Safety Plan will be reviewed by the field staff and contractors before beginning field operations at the site. Exploratory Drilling The borings will be drilled using an 8-inch hollow-stem auger drilling equipment to approximately 20 feet bgs for the shallow soil borings, and to approximately 50 feet bgs in the deep soil borings. The borings will be logged by a SECOR representative using the Unified Soil Classification System and standard geologic techniques. Soil samples for logging will be collected at 5-foot depth intervals using a California-modified split-spoon sampler. The sampler will be driven a maximum of 18 inches using a 140-pound hammer with a 30-inch drop. Soil samples for chemical analysis will be retained in brass liners, capped with Teflon squares and plastic end caps, and sealed in clean zip-lock bags . The samples will be placed on ice for transport to the laboratory accompanied by chain-of-custody documentation. Down- hole drilling and sampling equipment will be steam-cleaned prior to and following the completion of the soil boring. Down-hole sampling equipment will be washed in a tri-sodium phosphate or alconox solution between samples. Organic Vapor Procedures Soil samples collected at 5-foot depth intervals during drilling will be analyzed in the field for ionizable organic compounds using a photo-ionization detector (PID) with a 10 .2 eV lamp or a flame ionization detector (FID) . The test procedure will involve measuring approximately 30 grams from an undisturbed soil sample, placing this subsample in a sealed container (either a zip-lock bag or a mason jar). The container will be warmed for approximately 20 minutes (in the sun), then the head-space within will be tested for total organic vapor, measured in parts per million as benzene (ppm; volume/volume) . The instrument will be calibrated prior to drilling using a 100-ppm isobutylene standard (in air) and a sensitivity factor of 55, which relates the photo-ionization potential of benzene to that of isobutylene at 100 ppm. The results of the field testing will be noted on the boring logs. PID and FID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses. Groundwater Monitoring Well Installation The borings will be converted to a groundwater monitoring well by installing 2-inch diameter, flush-threaded, Schedule 40 PVC casing with 0. 020-inch factory-slotted screen. Approxi- mately 15 feet of screen will be placed in the bottom the shallow borings, and 5 feet of screen